tag:theconversation.com,2011:/fr/topics/food-science-982/articlesFood science – The Conversation2024-02-20T19:57:14Ztag:theconversation.com,2011:article/2213102024-02-20T19:57:14Z2024-02-20T19:57:14ZIf you’re worried about inflammation, stop stressing about seed oils and focus on the basics<figure><img src="https://images.theconversation.com/files/570530/original/file-20240122-27-pmcpjd.jpg?ixlib=rb-1.1.0&rect=0%2C7%2C4992%2C2799&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-asian-man-eyeglasses-choosing-vegetable-1248584587">Zephyr_p/Shutterstock</a></span></figcaption></figure><p>You’ve probably seen recent claims online seed oils are “toxic” and cause inflammation, cancer, diabetes and heart disease. But what does the research say? </p>
<p>Overall, if you’re worried about inflammation, cancer, diabetes and heart disease there are probably more important things to worry about than seed oils. </p>
<p>They may or may not play a role in inflammation (the research picture is mixed). What we do know, however, is that a high-quality diet rich in unprocessed whole foods (fruits, vegetables, nuts, seeds, grains and lean meats) is the number one thing you can to do <a href="https://theconversation.com/9-signs-you-have-inflammation-in-your-body-could-an-anti-inflammatory-diet-help-210468">reduce inflammation</a> and your risk of developing diseases. </p>
<p>Rather than focusing on seed oils specifically, reduce your intake of processed foods more broadly and focus on eating fresh foods. So don’t stress out too much about using a bit of seed oils in your cooking if you are generally focused on all the right things. </p>
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Read more:
<a href="https://theconversation.com/9-signs-you-have-inflammation-in-your-body-could-an-anti-inflammatory-diet-help-210468">9 signs you have inflammation in your body. Could an anti-inflammatory diet help?</a>
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<h2>What are seed oils?</h2>
<p>Seed oils are made from whole seeds, such as sunflower seeds, flax seeds, chia seeds and sesame seeds. These seeds are processed to extract oil. </p>
<p>The most common seed oils found at grocery stores include sesame oil, canola oil, sunflower oil, flaxseed oil, corn oil, grapeseed oil and soybean oil. </p>
<p>Seed oils are generally affordable, easy to find and suitable for many dishes and cuisines as they often have a high smoke point.</p>
<p>However, most people consume seed oils in larger amounts through processed foods such as biscuits, cakes, chips, muesli bars, muffins, dipping sauces, deep-fried foods, salad dressings and margarines. </p>
<p>These processed foods are “<a href="https://www.eatforhealth.gov.au/food-essentials/discretionary-food-and-drink-choices">discretionary</a>”, meaning they’re OK to have occasionally. But they are not considered necessary for a healthy diet, nor <a href="https://www.eatforhealth.gov.au/food-essentials/discretionary-food-and-drink-choices">recommended</a> in our national dietary guidelines, the <a href="https://www.eatforhealth.gov.au/guidelines/australian-guide-healthy-eating">Australian Guide for Healthy Eating</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A person holds some sunflower oil while standing in a supermarket." src="https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572040/original/file-20240129-29-4oyc8j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Seed oils often have a high smoke point.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-choosing-sunflower-oil-supermarket-close-2118886319">Gleb Usovich/Shutterstock</a></span>
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<h2>I’ve heard people say seed oils ‘promote inflammation’. Is that true?</h2>
<p>There are two essential types of omega fatty acids: omega-3 and omega-6. These are crucial for bodily functions, and we must get them through our diet since our bodies cannot produce them. </p>
<p>While all oils contain varying levels of fatty acids, some argue an excessive intake of a specific omega-6 fatty acid in seed oils called “linoleic acid” may contribute to inflammation in the body. </p>
<p>There is some evidence linoleic acid can be converted to arachidonic acid in the body and this may play a role in <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/arachidonic-acid">inflammation</a>. However, other <a href="https://nutritionandmetabolism.biomedcentral.com/articles/10.1186/1743-7075-8-36">research</a> doesn’t support the idea reducing dietary linoleic acid affects the amount of arachidonic acid in your body. The research picture is not clear cut.</p>
<p>But if you’re keen to reduce inflammation, the best thing you can do is aim for a healthy diet that is: </p>
<ul>
<li><p>high in antioxidants (found in fruits and vegetables)</p></li>
<li><p>high in “healthy”, unsaturated fatty acids (found in fatty fish, some nuts and olive oil, for example)</p></li>
<li><p>high in fibre (found in carrots, cauliflower, broccoli and leafy greens) and prebiotics (found in onions, leeks, asparagus, garlic and legumes)</p></li>
<li><p>low in processed foods.</p></li>
</ul>
<p>If reducing inflammation is your goal, it’s probably more meaningful to focus on these basics than on occasional use of seed oils.</p>
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<a href="https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A bowl containing bright, fresh vegetables, chicken and chickpeas sits on a table." src="https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=416&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=416&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=416&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=523&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=523&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572964/original/file-20240202-27-kyciv3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=523&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Choose foods high in fibre (like many vegetables) and prebiotics (like legumes).</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/grilled-chicken-rice-spicy-chickpeas-avocado-587607935">Kiian Oksana/Shutterstock</a></span>
</figcaption>
</figure>
<h2>What about seed oils and heart disease, cancer or diabetes risk?</h2>
<p>Some popular arguments against seed oils come from data from single studies on this topic. Often these are observational studies where researchers do not make changes to people’s diet or lifestyle.</p>
<p>To get a clearer picture, we should look at meta-analyses, where scientists combine all the data available on a topic. This helps us get a better overall view of what’s going on.</p>
<p>A 2022 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8924827/">meta-analysis</a> of randomised controlled trials investigated the relationship between supplementation with omega-6 fatty acid (often found in seed oils) and cardiovascular disease risk (meaning disease relating to the heart and blood vessels). </p>
<p>The researchers found omega-6 intake did not affect the risk for cardiovascular disease or death but that further research is needed for firm conclusions. Similar findings were observed in a <a href="https://pubmed.ncbi.nlm.nih.gov/30971107/">2019 review</a> on this topic.</p>
<p>The World Health Organization <a href="https://iris.who.int/bitstream/handle/10665/365671/9789240061644-eng.pdf?sequence=1&isAllowed=y">published a review and meta-analysis</a> in 2022 of observational studies (considered lower quality evidence compared to randomised controlled trials) on this topic. </p>
<p>They looked at omega-6 intake and risk of death, cardiovascular disease, breast cancer, mental health conditions and type 2 diabetes. The findings show both advantages and disadvantages of consuming omega-6.</p>
<p>The findings reported that, overall, higher intakes of omega-6 were associated with a 9% reduced risk of dying (data from nine studies) but a 31% increased risk of postmenopausal breast cancer (data from six studies).</p>
<p>One of the key findings from this review was about the ratio of omega-3 fatty acids to omega-6 fatty acids. A higher omega 6:3 ratio was associated with a greater risk of cognitive decline and ulcerative colitis (an inflammatory bowel condition). </p>
<p>A higher omega 3:6 ratio was linked to a 26% reduced risk of depression. These mixed outcomes may be a cause of confusion among health-conscious consumers about the health impact of seed oils. </p>
<p>Overall, the evidence suggests that a high intake of omega-6 fatty acids from seed oils is unlikely to increase your risk of death and disease.</p>
<p>However, more high-quality intervention research is needed. </p>
<h2>The importance of increasing your omega-3 fatty acids</h2>
<p>On top of the mixed outcomes, there is <a href="https://pubmed.ncbi.nlm.nih.gov/31010701/">clear evidence</a> increasing the intake of omega-3 fatty acids (often found in foods such as fatty fish and walnuts) is beneficial for health. </p>
<p>While some seed oils contain small amounts of omega-3s, they are not typically considered rich sources. </p>
<p>Flaxseed oil is an exception and is one of the few seed oils that is notably high in alpha-linolenic acid (sometimes shortened to ALA), an omega-3 fatty acid. </p>
<p>If you are looking to increase your omega-3 intake, it’s better to focus on other sources such as fatty fish (salmon, mackerel, sardines), chia seeds, hemp seeds, walnuts, and algae-based supplements. These foods are known for their higher omega-3 content compared to seed oils.</p>
<h2>The bottom line</h2>
<p>At the end of the day, it’s probably OK to include small quantities of seed oils in your diet, as long as you are mostly focused on eating fresh, unprocessed foods.</p>
<p>The best way to reduce your risk of inflammation, heart disease, cancer or diabetes is not to focus so much on seed oils but rather on doing your best to follow the <a href="https://www.eatforhealth.gov.au/guidelines/australian-guide-healthy-eating">Australian Guide for Healthy Eating</a>. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/how-is-decaf-coffee-made-and-is-it-really-caffeine-free-215546">How is decaf coffee made? And is it really caffeine-free?</a>
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<img src="https://counter.theconversation.com/content/221310/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lauren Ball works for The University of Queensland and receives funding from the National Health and Medical Research Council, Queensland Health and Mater Misericordia. She is a Director of Dietitians Australia, a Director of the Darling Downs and West Moreton Primary Health Network and an Associate Member of the Australian Academy of Health and Medical Sciences.</span></em></p><p class="fine-print"><em><span>Emily Burch is an Accredited Practising Dietitian and member of Dietitians Australia. </span></em></p>Rather than focusing on seed oils specifically, reduce your intake of processed foods more broadly and focus on eating fresh foods.Lauren Ball, Professor of Community Health and Wellbeing, The University of QueenslandEmily Burch, Lecturer, Southern Cross UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2020362024-02-19T00:42:34Z2024-02-19T00:42:34ZRun out of butter or eggs? Here’s the science behind substitute ingredients<figure><img src="https://images.theconversation.com/files/575492/original/file-20240213-28-yaukh5.jpg?ixlib=rb-1.1.0&rect=80%2C35%2C5784%2C3952&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/white-soup-on-brown-ceramic-bowl-wg5kaMtJ3Ts">Joanna Lopez/Unsplash</a></span></figcaption></figure><p>It’s an all too common situation – you’re busy cooking or baking to a recipe when you open the cupboard and suddenly realise you are missing an ingredient.</p>
<p>Unless you can immediately run to the shops, this can leave you scrambling for a substitute that can perform a similar function. Thankfully, such substitutes can be more successful than you’d expect.</p>
<p>There are a few reasons why certain ingredient substitutions work so well. This is usually to do with the chemistry and the physical features having enough similarity to the original ingredient to still do the job appropriately. </p>
<p>Let’s delve into some common ingredient substitutions and why they work – or need to be tweaked.</p>
<p><iframe id="IitfH" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/IitfH/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>Oils versus butter</h2>
<p>Both butter and oils belong to a chemical class called <a href="https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Map%3A_Fundamentals_of_General_Organic_and_Biological_Chemistry_(McMurry_et_al.)/23%3A_Lipids/23.01%3A_Structure_and_Classification_of_Lipids">lipids</a>. It encompasses solid, semi-solid and liquid fats.</p>
<p>In a baked product the “job” of these ingredients is to provide flavour and influence the structure and texture of the finished item. In cake batters, lipids contribute to creating an emulsion structure – this means combining two liquids that wouldn’t usually mix. In the baking process, this helps to create a light, fluffy crumb.</p>
<p>One of the primary differences between butter and oil is that butter is only about 80% lipid (the rest being water), while <a href="https://www.nutritionadvance.com/types-of-cooking-fats-and-oils/">oil is almost 100% lipid</a>. Oil creates a softer crumb but is still a great fat to bake with.</p>
<p>You can use a wide range of oils from different sources, such as olive oil, rice bran, avocado, peanut, coconut, macadamia and many more. Each of these may impart different flavours.</p>
<p>Other “butters”, such as peanut and cashew butter, aren’t strictly butters but pastes. They impart different characteristics and can’t easily replace dairy butter, unless you also add extra oil.</p>
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<a href="https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A block of yellow butter in an open silver foil wrapper" src="https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Nut ‘butters’ can’t replace dairy butter because their composition is too different.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/butter-good-butter-fat-nourishment-3411126/">congerdesign/Pixabay</a></span>
</figcaption>
</figure>
<h2>Aquafaba or flaxseed versus eggs</h2>
<p>Aquafaba is the liquid you drain from a can of legumes – such as chickpeas or lentils. It contains proteins, kind of how egg white also contains proteins.</p>
<p>The proteins in egg white include albumins, and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5912395/">aquafaba also contains albumins</a>. This is why it is possible to make meringue from egg whites, or from aquafaba if you’re after a vegan version.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-make-the-perfect-pavlova-according-to-chemistry-experts-196485">How to make the perfect pavlova, according to chemistry experts</a>
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<p>The proteins act as a foam stabiliser – they hold the light, airy texture in the product. The concentration of protein in egg white is a bit higher, so it doesn’t take long to create a stable foam. Aquafaba requires more whipping to create a meringue-like foam, but it will bake in a similar way. </p>
<p>Another albumin-containing alternative for eggs is <a href="https://foodstruct.com/compare/seeds-flaxseed-vs-egg">flaxseed</a>. These seeds form a thick gel texture when mixed with a little water. The texture is similar to raw egg and can provide structure and emulsification in baked recipes that call for a small amount of egg white. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/eggs-are-so-expensive-right-now-what-else-can-i-use-207837">Eggs are so expensive right now. What else can I use?</a>
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<h2>Lemon plus dairy versus buttermilk</h2>
<p>Buttermilk is the liquid left over after churning butter – it can be made from sweet cream, cultured/sour cream or whey-based cream. Buttermilk mostly <a href="https://www.journalofdairyscience.org/article/S0022-0302(06)72115-4/fulltext">contains proteins and fats</a>.</p>
<p>Cultured buttermilk has a somewhat tangy flavour. Slightly soured milk can be a good substitute as it contains similar components and isn’t too different from “real” buttermilk, chemically speaking.</p>
<p>One way to achieve slightly soured milk is by adding some lemon juice or cream of tartar to milk. Buttermilk is used in pancakes and baked goods to give extra height or volume. This is because the acidic (sour) components of buttermilk interact with baking soda, producing a light and airy texture. </p>
<p>Buttermilk can also influence flavour, imparting a slightly tangy taste to pancakes and baked goods. It can also be used in sauces and dressings if you’re looking for a lightly acidic touch. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A stack of fluffy pancakes dusted with sugar with a strawberry on top" src="https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Buttermilk is a common ingredient for making fluffy pancakes.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/pancakes-food-strawberry-plate-2801959/">Matthias_Groeneveld/Pixabay</a></span>
</figcaption>
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<h2>Honey versus sugar</h2>
<p>Honey is a <a href="https://resources.perkinelmer.com/lab-solutions/resources/docs/APP_Analysis-of-Sugars-in-Honey-012101_01.pdf">complex sugar-based syrup</a> that includes floral or botanical flavours and aromas. Honey can be used in cooking and baking, adding both flavour and texture (viscosity, softness) to a wide range of products.</p>
<p>If you add honey instead of regular sugar in baked goods, keep in mind that honey imparts a softer, moister texture. This is because it contains more moisture and is a humectant (that is, it likes to hold on to water). It is also less crystalline than sugar, unless you leave it to crystallise.</p>
<p>The intensity of sweetness can also be different – some people find honey is sweeter than its granular counterpart, so you will want to adjust your recipes accordingly.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of a slice of bread with golden honey pooling on top" src="https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Honey has a complex flavour and can taste sweeter than regular sugar.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/honey-bread-spoon-bio-nature-752145/">estelheitz/Pixabay</a></span>
</figcaption>
</figure>
<h2>Gluten-free versus regular flour</h2>
<p>Sometimes you need to make substitutions to avoid allergens, such as gluten – the protein found in cereal grains such as wheat, rye, barley and others. </p>
<p>Unfortunately, gluten is also the component that gives a nice, stretchy, squishy quality to bread.</p>
<p>To build this characteristic in a gluten-free product, it’s necessary to have a mixture of ingredients that work together to mimic this texture. Common ingredients used are corn or rice flour, xanthan gum, which acts as a binder and moisture holder, and tapioca starch, which is a good water absorbent and can aid with binding the dough. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/thank-glutens-complex-chemistry-for-your-light-fluffy-baked-goods-216869">Thank gluten's complex chemistry for your light, fluffy baked goods</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/202036/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paulomi (Polly) Burey does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>In a pinch, the water from a can of beans can replace eggs. But how does that work, exactly?Paulomi (Polly) Burey, Associate Professor (Food Science), University of Southern QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2209682024-02-08T14:00:57Z2024-02-08T14:00:57ZNigeria’s popular wara cheese has a short shelf life: we’ve found a way to keep it fresh for longer<p>Cheese is a highly nutritious food produced in hundreds of varieties around the world. It’s all made by fermenting milk but the results range widely in flavour, texture and end uses.</p>
<p>The global market value of cheese was about <a href="https://www.statista.com/topics/6586/global-cheese-market/">US$83.4 billion</a> in 2022 and is projected to exceed <a href="https://www.statista.com/topics/6586/global-cheese-market/">US$120 billion</a> in 2028.</p>
<p>In Nigeria, the most popular cheese is wara, a soft product with a mild, sweet taste and milky flavour. Wara is produced by coagulating cow’s milk with an extract of sodom apple (<em>Calotropis procera</em>, or bomubomu) and is traditionally sold in its whey (milk-like liquid), sometimes in a calabash, at room temperature. </p>
<p>Unhygienic conditions during production and sale, and lack of good packaging materials, can result in wara containing harmful <a href="https://www.sciencepub.net/nature/0403/06-0176-uzeh-ns.pdf">microorganisms</a> such as <em>E. coli</em>, <em>Staphylococcus aureus</em> and other bacteria. These can spoil the cheese or make a person ill after eating it.</p>
<p>Wara also has a very <a href="https://www.academia.edu/63932279/EFFECT_OF_PRESERVATIVES_AND_STORAGE_CONDITIONS_ON_MICROORGANISMS_IN_NIGERIAN_UNRIPENED_CHEESE_WARA">short shelf life</a> of about two or three days. This can be prolonged by refrigerating, drying or frying the cheese but these processes usually affect the taste, texture, colour, flavour and other sensory properties. They also discard the whey, which is an essential component of wara.</p>
<p>As Nigerian food scientists, we set out to find a way to preserve wara more effectively in its indigenous form. </p>
<p>We used different amounts of sorbic acid and natural ginger as preservatives, separately and in combination, and compared the microbial load in the wara samples. We <a href="https://www.academia.edu/63932279/EFFECT_OF_PRESERVATIVES_AND_STORAGE_CONDITIONS_ON_MICROORGANISMS_IN_NIGERIAN_UNRIPENED_CHEESE_WARA">found</a> that the best combination was 2.5% ginger with 0.05% sorbic acid, and that refrigeration was better than keeping the cheese at room temperature.</p>
<p>Extending its shelf life and improving its safety could boost demand and sales at all outlets, from informal to supermarkets. It would make a nutritious food more accessible and be good for producers and food processing businesses.</p>
<h2>Our research</h2>
<p>In our experiment we <a href="https://www.academia.edu/63932279/EFFECT_OF_PRESERVATIVES_AND_STORAGE_CONDITIONS_ON_MICROORGANISMS_IN_NIGERIAN_UNRIPENED_CHEESE_WARA">preserved</a> wara with chemical and natural preservatives: sorbic acid and ginger respectively. We kept the wara in whey for three weeks. </p>
<p>Sorbic acid was added to different samples at a concentration of 0.05% and 0.1%, which is below its maximum permissible limit of 0.3% in cheese according to the international <a href="https://dairyconsultant.co.uk/pdf/codex_specification_spreadable_processed_cheese">Codex Alimentarius standard</a>. The ginger (known locally as atalẹ) was prepared by washing and peeling rhizomes, slicing them into thin sheets, drying them in an oven at 50°C, and cooling, milling and sieving the dried product to obtain ginger powder. </p>
<p>Wara was produced by filtering 2 litres of fresh cow’s milk. The milk was divided into four portions (A, B, C and D). Preservatives were added in the following concentrations:</p>
<ul>
<li><p>5% ginger to portion A</p></li>
<li><p>2.5% ginger and 0.05% sorbic acid to portion B</p></li>
<li><p>0.1% sorbic acid to portion C</p></li>
<li><p>no preservatives in portion D.</p></li>
</ul>
<p>Each mixture was boiled and an extract of sodom apple leaves was added while boiling. The curd (the solid which separates from the liquid whey) was moulded into a cone shape. Each curd was transferred into a sterile plastic container, covered in whey and <a href="https://ijt.oauife.edu.ng/index.php/ijt/article/view/152">stored</a> in the refrigerator or at room temperature.</p>
<p>The populations and types of microorganisms associated with the preserved wara were determined every week. Microorganisms are important in fermenting milk and most are beneficial, but could cause spoilage if their growth is not controlled.</p>
<p>We also studied the effect of the preservatives on the sensory attributes such as taste, flavour, colour, appearance and texture of the wara samples. </p>
<h2>The outcome</h2>
<p>Preservation of wara with ginger and/or sorbic acid significantly reduced the population of microorganisms during storage. The use of 0.1% sorbic acid to preserve wara was the most effective in reducing bacterial and fungal count. The control sample without preservatives had the highest population of microorganisms. The addition of 2.5% ginger and 0.05% sorbic acid to wara reduced the microorganisms present and was much more effective than the addition of 5% ginger alone. </p>
<p>The physical examination of the stored wara showed that samples stored inside the refrigerator retained their fresh aroma throughout the period of storage. Those stored on the shelf at room temperature showed a change in aroma after two weeks. The samples without preservatives, stored at room temperature, had an offensive odour after a week. Spoilage of samples stored at room temperature was due to the higher rate of microbial metabolism. </p>
<p>There were no pathogenic (disease-causing) organisms in any of the wara samples throughout storage. </p>
<p>Wara samples stored inside the refrigerator had better quality in terms of microbial load, type of microorganisms, colour, texture and aroma than samples kept on the shelf at room temperature.</p>
<p>Freshly made wara samples without preservatives had the highest score for taste, flavour, colour, texture and overall acceptability. The values were not significantly different from the samples treated with 0.1% sorbic acid. Adding 2.5% ginger and 0.05% sorbic acid reduced the sensory scores of wara compared to the 0.1% sorbic acid sample. </p>
<p>In conclusion, we suggest that Nigerian wara can be produced on a large scale by using 0.1% sorbic acid or a combination of 2.5% ginger extract and 0.05% sorbic acid as a preservative. This will increase the time wara can be stored after production, thereby increasing the ability of the producers to scale up. </p>
<p>Preservation of wara can improve nutrition and create employment.</p><img src="https://counter.theconversation.com/content/220968/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Malomo Adekunbi Adetola works for Obafemi Awolowo University, Ile - Ife, Nigeria. She receives funding from Carnegie and the Dutch Ministry of Foreign Affairs. </span></em></p>Nigeria’s soft cheese, wara, could be made more widely available with new techniques to extend its shelf life.Malomo Adekunbi Adetola, Lecturer in Food Science and Technology, Obafemi Awolowo UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2192842023-12-19T13:14:58Z2023-12-19T13:14:58ZHow active are the microorganisms in your yogurt? We created a new tool to study probiotic activity — and made it out of cardboard<figure><img src="https://images.theconversation.com/files/565830/original/file-20231214-19-q51cra.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4244%2C2920&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Fermented foods can be a good source of probiotics. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/fermented-vegetables-sauerkraut-with-carrots-and-royalty-free-image/1279140719?phrase=probiotic+food&adppopup=true">Yulia Naumenko/Moment via Getty Images</a></span></figcaption></figure><p>Humans have been fermenting food and drinks — everything from kimchi and yogurt to beer and kombucha — for <a href="https://doi.org/10.3390%2Ffoods10112861">more than 13,000 years</a>. </p>
<p>Fermentation – a natural process that uses microorganisms to create alcohols and acids from carbohydrates – can preserve food so it lasts longer, and it can enhance the quality of a food by turning some components into more easily digestible forms. </p>
<p>Some fermented foods that contain live microorganisms are <a href="https://www.nccih.nih.gov/health/probiotics-what-you-need-to-know">called probiotics</a>, which can increase the shelf life of food and provide a range of additional benefits, like promoting a healthy <a href="https://theconversation.com/which-microbes-live-in-your-gut-a-microbiologist-tries-at-home-test-kits-to-see-what-they-reveal-about-the-microbiome-181392">gut microbiome</a> and lowering cholesterol levels.</p>
<p><a href="https://scienceweb.clemson.edu/uacl/">We are</a> <a href="https://scholar.google.com/citations?user=0kmXuxYAAAAJ&hl=en">chemists</a>, and our team wanted to figure out a way to understand which probiotics are the most active in the body. So we developed a cardboard sensor that could monitor the metabolic activity of probiotics.</p>
<h2>Probiotic health benefits</h2>
<p>As they are generally <a href="https://doi.org/10.1086/523331">considered safe</a>, probiotics are also one of the most popular dietary supplements in today’s market, accounting for more than <a href="https://finance.yahoo.com/news/global-probiotics-market-size-worth-075000774.html">US$50 billion</a> per year. </p>
<p><em>Lactobacillus</em>, <em>Bifidobacterium</em> and <em>Saccharomyces</em> are the most common probiotics. For example, food manufacturers use starter cultures of <em><a href="https://www.healthline.com/health/digestive-health/lactobacillus-bulgaricus">Lactobacillus bulgaricus</a></em> and <em><a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/streptococcus-thermophilus">Streptococcus thermophilus</a></em> to clot milk and make yogurt.</p>
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<figcaption><span class="caption">Probiotic-packed foods can help with gut health.</span></figcaption>
</figure>
<p><a href="https://doi.org/10.1038/s41575-019-0173-3">Recent studies</a> have also found that probiotics may prevent the development of harmful bacteria in the body, lower cholesterol levels, reduce constipation, control blood pressure, enhance the production of vitamins, improve calcium absorption and boost the immune system. </p>
<p>However, probiotics can only provide health effects when the microorganisms are alive, meaning they’re metabolically active and <a href="https://www.nature.com/articles/s41575-019-0173-3/figures/1">interacting with the host’s body</a>. So, the type of probiotic, its formulation, and how it’s processed become critically important. </p>
<h2>Analyzing probiotics</h2>
<p>Probiotics grow from individual cells into colonies. Food scientists can study probiotics by counting the number of viable cells – also called colony forming units – in the food to figure out how much they might grow and how active they’ll be. They can also study how probiotics respond to <a href="https://doi.org/10.1016/j.crfs.2021.04.006">a gastric juice made in the lab</a> to simulate how probiotics act in your gut. <a href="https://www.britannica.com/science/human-digestive-system/Gastric-secretion">Gastric juice</a> is the fluid secreted in your stomach during digestion. </p>
<p>But most of these tests are slow and involve expensive instruments and skilled personnel. That’s where our cardboard sensors come in.</p>
<p>Our research team has collaborated with a research <a href="https://www.iq.usp.br/trlcp/">team from Brazil</a> to develop a simple sensor that can measure the <a href="https://doi.org/10.1002/anse.202300056">metabolic activity of probiotic foods</a>. </p>
<p>We built the sensors using standard cardboard and a process called laser scribing. We use a laser to convert a small amount of the cardboard into carbon, making it electrically conductive. We also used gold nanoparticles, which further improve the sensor’s response by decreasing the material’s resistivity.</p>
<p>Lowering the resistivity of the material is important because the sensor detects the metabolic activity of bacteria via a type of chemical reaction called a <a href="https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:chemical-reactions/x2eef969c74e0d802:oxidation-reduction-redox-reactions/a/oxidation-number">redox reaction</a>. It can detect the oxidation of a molecule that is produced by one of the probiotics. </p>
<h2>Sensor findings</h2>
<p>Before testing, the team first calibrated the sensor using a popular probiotic yogurt widely available in U.S. stores as a model. For each test, we only needed to incubate 100 microliters of sample — about 1/50th of a teaspoon — for 10 minutes at room temperature. </p>
<p>Once we calibrated the sensors, we tested how metabolically active the microorganisms present in the sample were. We tested both beer and yogurt and found that the sensors could determine the metabolic activity more accurately than other tests that scientists usually use. </p>
<p><a href="https://doi.org/10.1002/anse.202300056">We also found</a> that the bacteria in the beer we tested, an unfiltered IPA, had more metabolic activity than the yogurts, which were popular brands Siggi’s, Yakult and Activia.</p>
<p>But, before you run to your local brewery, it’s important to note that the sensor only measures the total metabolic activity of the microorganisms present in the sample. It doesn’t detect anything about the type of activity or potential health effects.</p>
<p>While several groups have reported on the potential <a href="https://doi.org/10.3390%2Fnu15040844">health benefits of beer</a>, not all beers will provide these benefits. And keep in mind that a pint of an IPA carries beneficial bacteria, but also a typical alcohol content of between 6% and 8% and 180-200 calories.</p>
<p>Many <a href="https://doi.org/10.1016/j.tifs.2023.06.013">researchers have performed studies in this field</a> using more traditional probiotic foods that contain many of the microorganisms in your gut. Even in these cases, they’ve found that probiotics’ ability to correct specific health issues is probably limited. </p>
<p>Also, considering the way supplements containing probiotics <a href="https://www.forbes.com/sites/linhanhcat/2019/03/13/probiotics/?sh=35d1926719e8">are regulated</a>, it’s hard to say whether the products actually contain the type and amount of viable bacteria advertised on the label.</p>
<p>All things considered, the proposed sensor aims to provide a simple, portable and low-cost way to detect the activity of live bacteria. These sensors could one day help out in fields like health care.</p><img src="https://counter.theconversation.com/content/219284/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Financial support for this project has been provided by the Department of Chemistry at Clemson University and by CAPES (Brazil).</span></em></p><p class="fine-print"><em><span>George Chumanov does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Probiotics are great for your gut, but which sources contain the most beneficial bacteria? Newly developed sensors are helping scientists figure it out.Carlos D. Garcia, Professor of Chemistry, Clemson UniversityGeorge Chumanov, Professor of Chemistry, Clemson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2186872023-12-13T13:33:06Z2023-12-13T13:33:06ZNonalcoholic beer: New techniques craft flavorful brews without the buzz<figure><img src="https://images.theconversation.com/files/565024/original/file-20231211-25-f1xwdr.jpg?ixlib=rb-1.1.0&rect=333%2C369%2C6999%2C4928&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Brewers today are delivering nonalcoholic beers that are a far cry from the sweet, watery options of the past.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/asian-brewer-filling-beer-in-glass-from-tank-at-royalty-free-image/1402489303">Pramote Polyamate/Moment via Getty Images</a></span></figcaption></figure><p>The holiday season for me includes socializing over drinks with friends and family. But all the celebrating tends to catch up with my waistline, and by New Year’s Day, it’s time to get back in shape. Besides vowing to hit the gym more, my approach involves a “<a href="https://doi.org/10.3399/bjgp16X683173">Dry January</a>.” But as someone who teaches brewing science, spends a lot of time around breweries and bars, and thoroughly loves beer, abstaining is no easy task.</p>
<p>Thankfully, I can still enjoy beer while cutting back on my alcohol intake and calories by switching to nonalcoholic beers.</p>
<p>To some people, nonalcoholic beer sounds like an oxymoron, but newer techniques are producing tasty, high-quality options in this growing beverage category.</p>
<p>A nonalcoholic beer is usually a malt beverage that is <a href="https://beerandbrewing.com/dictionary/5VGRSbEfTv/">more than 0.0% and less than 0.5%</a> alcohol by volume (ABV). Producing a beer this low in alcohol requires the brewer to use practices and equipment uncommon to the general brewing process and to consider additional food safety precautions.</p>
<h2>Brewing regular beer</h2>
<p>Regular beer has four main ingredients: malted barley, hops, yeast and water.</p>
<p>When brewing beer, brewers extract sugars from malted barley – barley grains that have been partially germinated and then dried to make available the starches in the grain and enzymes that break them down. The malted barley then goes into the mash. That’s where the enzymes in the grain wake up and get to work breaking down the starches into smaller sugars. This step results in a sweet wort.</p>
<p>The brewer then boils the sweet wort and adds hops to provide bitterness, aroma and flavors. The hopped wort is then cooled and transferred to fermentation vessels where the brewer adds yeast. The yeast breaks down the sugars in the wort, releasing carbon dioxide and ethanol. Ethanol is the alcohol that makes beer “alcoholic.”</p>
<p>At this point we have beer. Beer’s alcohol by volume ranges from 3% to 13%, with <a href="https://www.thespruceeats.com/alcohol-by-volume-353204#:%7E:text=Alcohol%20by%20volume%2C%20or%20ABV,4.0%20to%207.0%20percent%20ABV.">most styles falling between 4% and 7%</a>.</p>
<h2>The challenge of removing alcohol</h2>
<p>Some of the more traditional approaches to making nonalcoholic beer are skipping the fermentation step or diluting a regular beer. These techniques can produce beers that are too sweet or one-note, lacking in flavor characters that come from fermentation. Advances in two alternative techniques – controlled fermentation and de-alcholization – have led to improved nonalcoholic beer quality.</p>
<p>Controlling fermentation involves using either low temperatures to limit yeast activity, strains of yeast that are unable to break down certain sugars, or wort that is less fermentable. Remember, it’s the living yeast cells that add alcohol to the mix as they digest sugars in the wort. By keeping yeast from doing its thing, brewers prevent the typical amount of alcohol from getting into the beer in the first place.</p>
<p>Alternatively, there are a few <a href="https://nabeerclub.com/how-non-alcoholic-beer-is-made/">common techniques to de-alcoholize regular-strength beer</a>.</p>
<p>Both steam distillation and vacuum distillation <a href="https://doi.org/10.1016/B978-0-12-816938-4.00006-9">separate out the ethanol by heating the beer</a>. Alcohol has a lower boiling point than water, so it gets removed as steam while the water portion of the beer is left behind. One problem with steam distillation is that it also takes out volatile aroma molecules and give the beer a cooked flavor. Vacuum distillation, however, significantly lowers the temperature needed to evaporate ethanol. The gentler temperatures help the nonalcoholic beer retain aroma and minimize the impacts on flavor. </p>
<p>Membrane filtration usually relies on <a href="https://www.britannica.com/science/reverse-osmosis">reverse osmosis</a>. This process uses filters with small pores that allow alcohol and water molecules to pass through, but not the larger molecules – like sugars, hops acids and oils, and proteins – that provide flavor, aroma and body in the beer. Rather than the liquid flowing through the membrane head-on, reverse osmosis uses cross-flow filtration. The liquids flow parallel to the filter surface.</p>
<p>The brewer establishes a pressure differential so the side where the beer starts is at higher pressure than the other side of the filter. This pressure pushes the alcohol and water molecules through the membrane pores. The filtration process results in two liquid streams being collected: a concentrated syrupy beer liquid and an alcohol-water mix. The final step is adding water back to the beer concentrate. </p>
<p>Of the de-alcoholization options, most beer lovers agree that vacuum distillation and reverse osmosis produce the best results.</p>
<h2>Challenges for brewing nonalcoholic beer</h2>
<p>These techniques often require additional brewing equipment that can be cost prohibitive to many smaller craft breweries. </p>
<p>One significant downside associated with the production of nonalcoholic beer is that removal of alcohol creates a product that is not as shelf-stable. <a href="https://news.cornell.edu/stories/2023/12/nonalcoholic-beer-higher-risk-foodborne-pathogens">Alcohol normally acts as a preservative</a> – without it, the beer can be vulnerable to contamination by microbes that are dangerous or spoil the beer. Because some of the common methods to produce nonalcoholic beers can use less hops, produce beer with more sugars and increase pH, the resulting product can be even more susceptible to bacterial growth.</p>
<p>Brewers need to take additional steps such as pasteurization, sterile filtration or the addition of preservatives <a href="https://www.brewersassociation.org/educational-publications/non-alcohol-beer-a-review-and-key-considerations/">to make nonalcoholic beer safe</a>.</p>
<h2>Nonalcoholic beer is a growth market</h2>
<p>Regardless of the challenges and costs to produce safe nonalcoholic beer, the market is growing steadily. While nonalcoholic sales in the U.S. are comparatively small, currently representing around <a href="https://www.cnbc.com/2022/12/30/non-alcoholic-beer-set-to-continue-to-grow-in-2023.html">2% of total sales</a>, they experienced <a href="https://www.wsj.com/business/retail/non-alcoholic-beer-sales-alcohol-consumption-habits-aaa2e19c">31% average growth over the past four years</a> even as other alcoholic beverage market segments languished. In other global markets, nonalcoholic sales have performed even better.</p>
<p>A few factors explain greater interest in nonalcoholic beers.</p>
<p>First, there’s been a steady <a href="https://news.gallup.com/poll/509690/young-adults-drinking-less-prior-decades.aspx#:%7E:text=The%20decline%20in%20young%20adults,among%20both%20older%20age%20groups.">decline in alcohol consumption among younger generations</a>, along with a trend toward adopting more healthy lifestyles.</p>
<p>Second, nonalcoholic products have been <a href="https://punchdrink.com/articles/nonalcoholic-beer-golden-age/">successfully marketed</a> not only to nondrinkers but to regular beer consumers. Regular beer drinkers who enjoy the taste of beer and not the intoxicating aspect, like me, can guiltlessly enjoy a nonalcoholic beer, even during the workday. Marketing campaigns have also focused on nonalcoholic beer being a lower calorie alternative since it doesn’t contain <a href="https://www.nhs.uk/live-well/alcohol-advice/calories-in-alcohol/">calorie-dense alcohol</a>.</p>
<p>It also doesn’t hurt that the quality of nonalcoholic beer has significantly improved since its early days. Nonalcoholic today is not the watery, overly sweet or one-note product that it was in the past. Many recent technological advances in production help nonalcoholic beer maintain fermentation characteristics derived from the malts, hops and yeast, thus providing a more balanced and pleasant product that tastes like “real” beer.</p><img src="https://counter.theconversation.com/content/218687/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Clark Danderson is a member of the Brewers Association. </span></em></p>Nonalcoholic beer may sound like an oxymoron, but newer techniques are producing tasty, high-quality options in this growing beverage category.Clark Danderson, Assistant Professor of Hospitality Management and Director of Brewing Science and Operations, Auburn UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2155462023-10-31T19:17:51Z2023-10-31T19:17:51ZHow is decaf coffee made? And is it really caffeine-free?<figure><img src="https://images.theconversation.com/files/556740/original/file-20231030-21-uurqzu.jpg?ixlib=rb-1.1.0&rect=133%2C47%2C6059%2C3540&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/gray-metal-tool-aaHwnxgBmHs">Volodymyr Proskurovskyi/Unsplash</a></span></figcaption></figure><p>Coffee is one of the most popular drinks in the world, and its high levels of caffeine are among the main reasons why. It’s a natural stimulant that provides an energy buzz, and we just can’t get enough.</p>
<p>However, some people prefer to limit their caffeine intake <a href="https://pubmed.ncbi.nlm.nih.gov/12684194/">for health</a> or other reasons. Decaffeinated or “decaf” coffee is widely available, and its consumption is reported to be <a href="https://www.coffeebeanshop.com.au/coffee-blog/decaf-coffee-market-worth-2145-billion-by-2025-at-69">on the rise</a>.</p>
<p>Here’s what you need to know about decaf coffee: how it’s made, the flavour, the benefits – and whether it’s actually caffeine-free.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-four-reasons-to-have-another-cup-of-coffee-40390">Health Check: four reasons to have another cup of coffee</a>
</strong>
</em>
</p>
<hr>
<h2>How is decaf made?</h2>
<p>Removing caffeine while keeping a coffee bean’s aroma and flavour intact isn’t a simple task. Decaf coffee is made by stripping green, unroasted coffee beans of their caffeine content and relies on the fact that <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6318762/#:%7E:text=Caffeine%20(Figure%201a)%20being,(15%20g%2FL).">caffeine dissolves</a> in water.</p>
<p>Three main methods are used for removing caffeine: chemical solvents, liquid carbon dioxide (CO₂), or plain water with special filters. </p>
<p>The additional steps required in all of these processing methods are why decaf coffee is often more expensive. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A close-up of a small branch with bright green berries on it" src="https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/556561/original/file-20231030-27-ab4y1v.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Coffee beans are not actually beans – they are the hard seeds nestled inside the fruit of the coffee plant.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/green-leaf-budded-during-daytime-VMJtKiREtMc">Marc Babin/Unsplash</a></span>
</figcaption>
</figure>
<h2>Solvent-based methods</h2>
<p>Most decaf coffee is made using <a href="https://www.tandfonline.com/doi/epdf/10.1080/10408699991279231?needAccess=true">solvent-based</a> methods as it’s the cheapest process. This method breaks down into two further types: <a href="https://www.sciencedirect.com/science/article/abs/pii/B9780123849472001835">direct and indirect</a>.</p>
<p>The <strong>direct method</strong> involves steaming the coffee beans and then repeatedly soaking them in a chemical solvent (usually methylene chloride or ethyl acetate) which binds to the caffeine and extracts it from the beans.</p>
<p>After a pre-determined time, the caffeine has been extracted and the coffee beans are steamed once more to remove any residual chemical solvent. </p>
<p>The <strong>indirect method</strong> still uses a chemical solvent, but it doesn’t come into direct contact with the coffee beans. Instead, the beans are soaked in hot water, then the water is separated from the beans and treated with the chemical solvent. </p>
<p>The caffeine bonds to the solvent in the water and is evaporated. The caffeine-free water is then returned to the beans to reabsorb the coffee flavours and aromas. </p>
<p>The solvent chemicals (particularly methylene chloride) used in these processes are a source of controversy around decaf coffee. This is because <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/dichloromethane">methylene chloride</a> is suggested to be mildly carcinogenic in high doses. Methylene chloride and ethyl acetate are commonly used in paint stripper, nail polish removers and degreaser.</p>
<p>However, both the <a href="https://www.foodstandards.gov.au/code/pages/default.aspx">Australian New Zealand Food Standards Code</a> and <a href="https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm?fr=173.255">the United States Food and Drug Administration</a> permit the use of these solvents to process decaf. They also have strict limits on the amount of the chemicals that can still be present on the beans, and in reality <a href="https://www.chemicals.co.uk/blog/how-dangerous-is-methylene-chloride">practically no solvent</a> is left behind.</p>
<h2>Non-solvent-based methods</h2>
<p>Non-solvent-based methods that use liquid carbon dioxide or water are becoming increasingly popular as they don’t involve chemical solvents.</p>
<p>In the <a href="https://www.tandfonline.com/doi/pdf/10.1080/10408699991279231"><strong>CO₂ method</strong></a>, liquid carbon dioxide is pumped into a high-pressure chamber with the beans, where it binds to the caffeine and is then removed through high pressure, leaving behind decaffeinated beans.</p>
<p>The <strong>water method</strong> (also known as the Swiss water process) is exactly what it sounds like – it <a href="http://publication.eiar.gov.et:8080/xmlui/bitstream/handle/123456789/3234/ECSS%20Proceeding%20Final.pdf?sequence=1#page=294">involves extracting caffeine</a> from coffee beans using water. There are variations on this method, but the basic steps are as follows. </p>
<p>For an initial batch, green coffee beans are soaked in hot water, creating an extract rich in caffeine and flavour compounds (the flavourless beans are then discarded). This green coffee extract is passed through activated charcoal filters, which trap the caffeine molecules while allowing the flavours to pass through.</p>
<p>Once created in this way, the caffeine-free extract can be used to soak a new batch of green coffee beans – since the flavours are already saturating the extract, the only thing that will be dissolved from the beans is the caffeine. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/8531vyP7Z5U?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<h2>Is caffeine fully removed from decaf?</h2>
<p>Switching to decaf may not be as caffeine free as you think. </p>
<p>It is unlikely that 100% of the caffeine will be successfully <a href="https://pubmed.ncbi.nlm.nih.gov/8603790/">stripped from the coffee beans</a>. Just like the caffeine content of coffee can vary, some <a href="https://pubmed.ncbi.nlm.nih.gov/17132260/">small amounts</a> of caffeine are still present in decaf. </p>
<p>However, the amount is quite modest. You would need to drink more than ten cups of decaf to reach the caffeine level typically present in <a href="https://academic.oup.com/jat/article/30/8/611/714415">one cup of caffeinated coffee</a>.</p>
<p>Australia <a href="https://www.foodstandards.gov.au/code/Documents/1.1.2%20Definitions%20v157.pdf">does not require</a> coffee roasters or producers to detail the process used to create their decaf coffee. However, you might find this information on some producers’ websites if they have chosen to advertise it.</p>
<h2>Does decaf coffee taste different?</h2>
<p>Some people say decaf tastes different. Depending on how the beans are decaffeinated, some aromatic elements may be co-extracted with the caffeine <a href="https://pubmed.ncbi.nlm.nih.gov/23745606/">during the process</a>.</p>
<p>Caffeine also contributes to the bitterness of coffee, so when the caffeine is removed, so is <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8948847/">some of the bitterness</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A tub of partially roasted coffee beans in a pale tan colour" src="https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/556739/original/file-20231030-23-t3sdwn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Caffeine contributes some of the bitterness of coffee, but there are also plenty of flavour compounds that develop in green beans as they are roasted to a rich, dark brown.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/person-holding-brown-seed-XpyD7z6AP4g">Joshua Newton/Unsplash</a></span>
</figcaption>
</figure>
<h2>Do caffeinated and decaf coffee have the same health benefits?</h2>
<p>The health benefits found for drinking decaf coffee are similar to that of caffeinated coffee, including a lower risk of type 2 diabetes, some cancers and overall <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5696634/">mortality</a>.
More recently, coffee has been linked with improved weight management over time.</p>
<p>Most of the health benefits have been shown by drinking <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5696634/">three cups</a> of decaf per day. </p>
<p>Moderation is key, and remember that the greatest health benefits will come from having a <a href="https://theconversation.com/what-is-a-balanced-diet-anyway-72432">balanced diet</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/can-coffee-help-you-avoid-weight-gain-heres-what-the-science-says-214954">Can coffee help you avoid weight gain? Here's what the science says</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/215546/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lauren Ball works for The University of Queensland and receives funding from the National Health and Medical Research Council, Queensland Health and Mater Misericordia. She is a Director of Dietitians Australia, a Director of the Darling Downs and West Moreton Primary Health Network and an Associate Member of the Australian Academy of Health and Medical Sciences.</span></em></p><p class="fine-print"><em><span>Emily Burch works for Southern Cross University.</span></em></p>Some coffee lovers can’t do without their hit of caffeine. But if you prefer decaf, here’s the intriguing science of how it’s made, why it costs more – and how much caffeine makes it to your cup.Lauren Ball, Professor of Community Health and Wellbeing, The University of QueenslandEmily Burch, Dietitian, Researcher & Lecturer, Southern Cross UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2151172023-10-19T12:30:15Z2023-10-19T12:30:15ZRancid food smells and tastes gross − AI tools may help scientists prevent that spoilage<figure><img src="https://images.theconversation.com/files/554034/original/file-20231016-21-91k6p2.jpg?ixlib=rb-1.1.0&rect=44%2C9%2C2073%2C1400&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Pantry staples can go rancid when exposed to oxygen. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/unrecognizable-woman-organising-pantry-legumes-and-royalty-free-image/1445167928?phrase=pantry&adppopup=true">Daniel de la Hoz/Moment</a></span></figcaption></figure><p>Have you ever bitten into a nut or a piece of chocolate, expecting a smooth, rich taste, only to encounter an unexpected and unpleasant chalky or sour flavor? That taste is rancidity in action, and it affects pretty much every product in your pantry. Now <a href="https://www.forbes.com/advisor/in/business/software/what-is-ai/">artificial intelligence</a> can help scientists tackle this issue more precisely and efficiently.</p>
<p>We’re a group of chemists who study ways to extend the life of food products, including those that go rancid. We recently <a href="https://doi.org/10.1021/acs.jafc.3c05462">published a study</a> describing the advantages of AI tools to help keep oil and fat samples fresh for longer. Because oils and fats are common components in many food types, including chips, chocolate and nuts, the outcomes of the study could be broadly applied and even affect other areas, including cosmetics and pharmaceuticals. </p>
<h2>Rancidity and antioxidants</h2>
<p><a href="https://www.scienceabc.com/pure-sciences/what-is-rancidity.html">Food goes rancid</a> when it’s exposed to the air for a while – a process called oxidation. In fact, many common ingredients, but <a href="https://www.britannica.com/science/lipid">especially lipids</a>, which are fats and oils, react with oxygen. The presence of heat or UV light can accelerate the process.</p>
<p>Oxidation leads to the formation of smaller molecules such as <a href="https://www.britannica.com/science/ketone">ketones</a>, <a href="https://www.britannica.com/science/aldehyde">aldehydes</a> and <a href="https://www.britannica.com/science/fatty-acid">fatty acids</a> that give rancid foods a characteristic rank, strong and metallic scent. Repeatedly consuming rancid foods <a href="https://doi.org/10.1002/mnfr.200600303">can threaten your health</a>.</p>
<p>Fortunately, both nature and the food industry have an excellent shield against rancidity – antioxidants. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/LXHvlYdCL8A?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Foods turn rancid from a process called oxidation.</span></figcaption>
</figure>
<p><a href="https://www.healthline.com/nutrition/antioxidants-explained#supplements">Antioxidants</a> include a broad range of natural molecules, like vitamin C, and synthetic molecules capable of protecting your food from oxidation. </p>
<p>While there are <a href="https://doi.org/10.1111/j.1541-4337.2009.00085.x">a few ways antioxidants work</a>, overall they can neutralize many of the processes that cause rancidity and preserve the flavors and nutritional value of your food for longer. Most often, customers don’t even know they are consuming added antioxidants, as food manufacturers typically add them in small amounts during preparation. </p>
<p>But you can’t just sprinkle some vitamin C on your food and expect to see a preservative effect. Researchers have to carefully choose <a href="https://doi.org/10.1016/j.tifs.2023.02.003">a specific set of antioxidants</a> and precisely calculate the amount of each. </p>
<p>Combining antioxidants does not always strengthen their effect. In fact, there are cases in which using the wrong antioxidants, or mixing them with the wrong ratios, can decrease their protective effect – that’s called <a href="https://doi.org/10.1007/s11101-019-09658-4">antagonism</a>. Finding out which combinations work for which types of food requires many experiments, which are time-consuming, require specialized personnel and increase the food’s overall cost. </p>
<p>Exploring all possible combinations would require an enormous amount of time and resources, so researchers are stuck with a few mixtures that provide only some level of protection against rancidity. Here’s where AI comes into play.</p>
<h2>A use for AI</h2>
<p>You’ve probably seen <a href="https://theconversation.com/gliding-not-searching-heres-how-to-reset-your-view-of-chatgpt-to-steer-it-to-better-results-205819">AI tools like ChatGPT</a> in the news or played around with them yourself. These types of systems can <a href="https://theconversation.com/are-you-part-robot-a-linguistic-anthropologist-explains-how-humans-are-like-chatgpt-both-recycle-language-203477">take in big sets of data</a> and identify patterns, then generate an output that could be useful to the user.</p>
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<figcaption><span class="caption">AI tools have changed how many scientists conduct research.</span></figcaption>
</figure>
<p>As chemists, we wanted to teach an AI tool how to look for new combinations of antioxidants. For this, we selected a type of AI capable of working with <a href="https://doi.org/10.1021/ci00057a005">textual representations</a>, which are written codes describing the chemical structure of each antioxidant. First, we fed our AI a list of about a million chemical reactions and taught the program some simple chemistry concepts, like how to identify important features of molecules.</p>
<p>Once the machine could recognize general chemical patterns, like how certain molecules react with each other, we fine-tuned it by teaching it some more advanced chemistry. For this step, our team used a database of almost 1,100 mixtures previously described in the research literature. </p>
<p>At this point, the AI could predict the effect of combining any set of two or three antioxidants in under a second. Its prediction aligned with the effect described in the literature 90% of the time.</p>
<p>But these predictions didn’t quite align with the experiments our team performed in the lab. In fact, we found that our AI was able to correctly predict only a few of the oxidation experiments we performed with real lard, which shows the complexities of transferring results from a computer to the lab.</p>
<h2>Refining and enhancing</h2>
<p>Luckily, AI models aren’t static tools with predefined yes and no pathways. They’re <a href="https://theconversation.com/a-celebrated-ai-has-learned-a-new-trick-how-to-do-chemistry-182031">dynamic learners</a>, so our research team can continue feeding the model new data until it sharpens its predictive capabilities and can accurately predict the effect of each antioxidant combination. The more data the model gets, the more accurate it becomes, much like how humans grow through learning.</p>
<p>We found that adding about 200 examples from the lab enabled the AI to learn enough chemistry to predict the outcomes of the experiments performed by our team, with only a slight difference between the predicted and the real value. </p>
<p>A model like ours may be able to assist scientists developing better ways to preserve food by coming up with the best antioxidant combinations for the specific foods they’re working with, kind of like having a very clever assistant.</p>
<p>The project is now exploring more effective ways to train the AI model and looking for ways to further improve its predictive capabilities.</p><img src="https://counter.theconversation.com/content/215117/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This project was funded by a grant from the South Carolina Department of Agriculture ACRE Competitive Grant Program. </span></em></p><p class="fine-print"><em><span>Lucas de Brito Ayres does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Pantry food can go bad if exposed to oxygen, but an AI model might help develop more effective preservatives and keep food fresher for longer.Carlos D. Garcia, Professor of Chemistry, Clemson UniversityLucas de Brito Ayres, PhD Candidate in Chemistry, Clemson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2116132023-08-21T20:17:39Z2023-08-21T20:17:39ZCalories and kilojoules: how do we know the energy content of food, and how accurate are the labels?<figure><img src="https://images.theconversation.com/files/543631/original/file-20230821-17-t1wke.jpeg?ixlib=rb-1.1.0&rect=0%2C29%2C3888%2C2555&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Everything we consume contains energy our bodies use to move, grow and maintain health. To work out how much energy is in different foods and drinks, we need to first look at a few core concepts.</p>
<p>Firstly, you’ve probably heard of the units of measurement for energy – calories – as well as the metric equivalent, which is joules. One calorie is defined as the amount of energy required to raise the temperature of 1 gram of water by 1°C.</p>
<p>In human nutrition, the amounts of energy needed to maintain health, and to fuel a body, are much larger than the tiny singular calories used to heat up a gram of water. So, the term “calorie” in nutrition commonly refers to a <a href="https://www.sciencedirect.com/science/article/pii/S0022316622085546">kilocalorie</a> (or kcal), which is 1,000 calories. When you see the word “calories” on a nutrition label, it’s likely referring to kcals.</p>
<p>The energy stored in food and drinks is released when the body breaks down one or more of the four macronutrients inside the food (carbohydrates, proteins, fats, alcohol). The body then uses that energy for activities such as keeping our heart beating, our lungs breathing and our muscles moving. </p>
<p>When energy in food is estimated, it is the amount of energy food and drinks provide for these bodily processes. The four macronutrients provide <a href="https://www.sciencedirect.com/science/article/pii/S0002916522039454">different amounts of energy</a>:</p>
<ol>
<li> 1 gram of carbohydrate provides about 4 kcal of energy</li>
<li> 1 gram of fat provides about 9 kcal of energy</li>
<li> 1 gram of protein provides about 4 kcal of energy</li>
<li> 1 gram of alcohol provides about 7 kcal of energy.</li>
</ol>
<h2>How are calories estimated?</h2>
<p>There are two ways to estimate the amount of energy in food and drinks.</p>
<p>The first is called “bomb calorimetry”. This gold-standard method involves placing a small sample of food or drink inside a device known as a bomb calorimeter. The food is burned in the presence of oxygen, releasing heat. </p>
<p>The amount of heat released is directly related to the amount of energy in the food, allowing a calculation to be made. This method is most commonly used for foods rich in fats and is considered the most reliable (but expensive) method.</p>
<p>The second method, the Atwater system, is a much less expensive method for estimating energy content. It is more commonly used when calculating energy of most food and drinks sold in supermarkets. Named after legendary food researcher <a href="https://www.sciencedirect.com/science/article/pii/S0022316622065336">Wilbur Atwater</a>, this system uses a standard conversion factor for each macronutrient found in food and drinks. By estimating the amount of each of the four macronutrients, an approximate calculation of the total energy can be made. </p>
<p>However, this method requires detailed knowledge of the ingredients within composite foods (such as muesli bars or hamburgers) – which may reduce accuracy. There is also a margin of error to expect with the Atwater system, because it assumes each ingredient is always the same in composition. </p>
<p>For example, a cup of oats grown in one part of the country won’t necessarily have the exact same nutritional content as another cup of oats grown elsewhere, due to climate and soil differences. So, this system is an estimation based on an average.</p>
<p>Importantly, both methods estimate the amount of energy <em>in</em> food and drinks. But the actual energy our bodies extract from these foods and drinks can vary due to factors such as individual differences in digestion and absorption, as well as food processing and cooking methods.</p>
<h2>Why do foods have calories written on them?</h2>
<p>In Australia, it’s a <a href="https://www.foodstandards.gov.au/consumer/labelling/panels/Pages/default.aspx">legal requirement</a> for packaged food items to have a nutrition information panel that displays the number of kcal it contains. </p>
<p>However, homemade food items sold at places like a fresh market may not be required to provide a nutrition information panel. This will depend on the type of food being sold and the scale of the business operation.</p>
<p>Fresh foods such as fruit, vegetables and meat also don’t require a nutrition information panel. To find out the number of kcal in them, you can either run an experiment with a bomb calorimeter or look up an estimated value in an online nutrition database.</p>
<p>Food composition databases such as <a href="https://www.calorieking.com/us/en/">CalorieKing</a> compile information about the energy and nutrient content of various foods. Dietitians and other health professionals often use these databases to estimate the energy content of foods to inform dietary recommendations.</p>
<h2>Different international standards</h2>
<p>Both kJ and kcal refer to energy – they are just two different units of measurements (such as how inches and centimetres are two different units for measuring length). Kilojoules (kJ) is part of the International System of Units (SI).</p>
<p>Australia, New Zealand and some parts of Europe use kJ. The United States and the United Kingdom use kcal. To convert between calories and kilojoules you use the conversion factors: </p>
<ul>
<li>1 kcal = 4.184 kJ</li>
<li>1 kJ = 0.24 kcal (about ¼).</li>
</ul>
<p>For example, if you have a packet of chips with an energy content of 200 kcal, you can convert it to kJ as follows: 200 kcal × 4.184 = 836.8 kJ.</p>
<p>As for how many calories are acceptable to eat, the Australian Guidelines for Healthy Eating estimate the average adult requires about 7,000kJ or 1,670Kcal every day. However, differences in age, gender, size, health and physical activity will influence how much energy a person needs. </p>
<p>To estimate your personal energy requirements, you can use this <a href="https://www.eatforhealth.gov.au/nutrient-reference-values/nutrients-dietary-energy-calculator#results-energy">nutrients and dietary energy calculator</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/its-time-to-bust-the-calories-in-calories-out-weight-loss-myth-199092">It's time to bust the 'calories in, calories out' weight-loss myth</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/211613/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lauren Ball works for The University of Queensland and receives funding from the National Health and Medical Research Council, Queensland Health, Royal Australian College of General Practitioners and Mater Misericordia. She is a Director of Dietitians Australia, a Director of the Darling Downs and West Moreton Primary Health Network and an Associate Member of the Australian Academy of Health and Medical Sciences.</span></em></p><p class="fine-print"><em><span>Emily Burch works for Southern Cross University. </span></em></p><p class="fine-print"><em><span>Katelyn Barnes works for The University of Queensland and ACT Health. </span></em></p>There are two main methods used to calculate the energy content in food and drinks.Lauren Ball, Professor of Community Health and Wellbeing, The University of QueenslandEmily Burch, Dietitian, Researcher & Lecturer, Southern Cross UniversityKatelyn Barnes, Postdoctoral Research Fellow, School of Human Movement and Nutrition Sciences, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2050382023-07-24T04:17:13Z2023-07-24T04:17:13ZHow does ice cream work? A chemist explains why you can’t just freeze cream and expect results<figure><img src="https://images.theconversation.com/files/538876/original/file-20230724-79526-ui0tqq.jpg?ixlib=rb-1.1.0&rect=181%2C623%2C6237%2C3842&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/homemade-neopolitan-ice-cream-vanilla-chocolate-1093782722">Shutterstock</a></span></figcaption></figure><p>Ice cream seems like a simple concept. Take some dairy, add some sugar and flavours, and freeze.</p>
<p>But to get a perfectly creamy, smoothly textured frozen treat, we need more than just a low temperature – it takes a careful interplay of chemistry and three states of matter: solid, liquid and gas.</p>
<h2>What’s in the box?</h2>
<p>Commercial ice cream includes many ingredients: air, water, milk fat, so-called milk solids (mainly milk proteins and lactose), sweeteners, stabilisers, emulsifiers and flavours. The ingredients are mixed and <a href="https://theconversation.com/e-coli-in-milk-wont-necessarily-make-you-sick-but-it-signals-risks-from-other-bacteria-119229">pasteurised for food safety</a>.</p>
<p>Homemade ice creams tend to use milk, heavy cream, sugar and flavourings, such as fruit, berries, or chocolate. The exact quantities vary with the recipe, but the processing steps are similar.</p>
<p><a href="https://www.hsph.harvard.edu/nutritionsource/milk/">Milk is composed</a> of everything a young cow needs to grow and develop – water, fats, carbohydrates, proteins, minerals and vitamins. These components respond in different ways when they are frozen.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/crying-over-plant-based-milk-neither-science-nor-history-favours-a-dairy-monopoly-123852">Crying over plant-based milk: neither science nor history favours a dairy monopoly</a>
</strong>
</em>
</p>
<hr>
<h2>First, the crystals</h2>
<p>As the mixture of ice cream ingredients is cooled down, small clusters of water molecules assemble to form <a href="https://theconversation.com/how-do-snowflakes-form-is-each-snowflake-really-unique-why-is-some-snow-light-and-fluffy-or-heavy-the-amazing-science-of-snow-196269">tiny ice crystals</a>. The size of the ice crystals is responsible for the mouth feel of the ice cream – the <a href="https://ift.onlinelibrary.wiley.com/doi/full/10.1111/j.1541-4337.2009.00101.x">smaller the crystals, the smoother the feel</a>.</p>
<p>If the crystallisation is not well controlled, these crystals can get very large. Ice cream makers (commercial or for home use) ensure small ice crystals by agitating or beating the liquid as it freezes. This keeps the water molecules moving and prevents the crystals from growing larger.</p>
<p>The mixing process also incorporates air, which is the secret ingredient to give ice cream a lighter texture.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close up of ivory coloured ice cream being churned in a stainless steel container" src="https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526974/original/file-20230518-23-jkyrps.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Without mixing during the freezing process, the ice crystals in the milk or cream will be too large to yield the texture that defines ice cream.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/close-on-industrial-ice-cream-mixing-1584957778">Shutterstock</a></span>
</figcaption>
</figure>
<h2>Next, the fat</h2>
<p>The fat in the milk exists as globules surrounded by proteins. These proteins bridge the fat and the water, helping to keep the fats suspended. (Milk looks white because light scatters off these fat globules.)</p>
<p>These dairy fat molecules have different properties at different temperatures. At room temperature they are semi-solids (like butter), and are about two-thirds solid when at 0°C. </p>
<p>The fat globules can stick together – that’s why you get a layer of cream on top of unprocessed milk. A process called <a href="https://iufost.org/iufostold/wp-content/uploads/2020/05/98-Milk-Homogenization.pdf">homogenisation</a> forces the milk through a small opening under very high pressure, breaking large fat globules down into smaller ones. This process makes many small fat globules – as many as a trillion per litre. Homogenised milk ensures the mixture will freeze evenly, and separated fats won’t get stuck to the mixing machinery.</p>
<p>Freezing the fat globules makes them clump together, with the surrounding proteins acting as bridges to other fat molecules and to the ice crystals. These fats melt in your mouth, giving a creamy feel and taste.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/slip-slop-slurp-the-surprising-science-of-sunscreen-sand-and-ice-cream-169155">Slip, slop, slurp! The surprising science of sunscreen, sand and ice cream</a>
</strong>
</em>
</p>
<hr>
<h2>Then, the sugar</h2>
<p>The sugar and other dissolved ingredients in milk are also essential to the final texture of ice cream. The presence of sugars in the water lowers the mixture’s freezing temperature to below 0°C. </p>
<p>Here’s why that’s important. As ice crystals start to form, the concentration of sugars and other dissolved materials in the <a href="https://www.tandfonline.com/doi/full/10.1081/FRI-100100289">unfrozen liquid increases</a>, which further <a href="https://theconversation.com/salt-doesnt-melt-ice-heres-how-it-actually-makes-winter-streets-safe-110870">lowers its freezing point</a>. By the time the majority of the ice crystals have formed, the resulting liquid is very concentrated in sugars. </p>
<p>This concentrated liquid, known as the “serum”, bridges <em>between</em> the ice crystals, solid fat globules and air bubbles. The serum remains a liquid well below 0°C and adds enough flexibility to the mixture so the ice cream can still be scooped or shaped.</p>
<p>In this way, the unique chemical properties of water, fats, proteins and sugars come together with air to give the solid, liquid and gas mixture we know and love.</p>
<h2>Not everything is ‘ice cream’</h2>
<p>What’s called “ice cream” is actually governed by a <a href="https://www.legislation.gov.au/Series/F2015L00424">food standards code</a>. That’s why not all frozen desserts can be legally called ice cream, because they don’t contain enough milk fat.</p>
<p>There are lots of variations on the standard ice cream recipe. Gelato uses more sugar, incorporates less air, and typically has less fats and other solids. Sorbets do away with the dairy and typically contain more sugar, but have historically used egg or gelatin as a protein source. </p>
<p>Regardless of the exact recipe, the fundamental ice crystal formation, fat solidification, and serum phase separation steps are the same.</p>
<p>Product names like “soft serve”, “dairy dessert”, or “ice confection” are often an indication the ingredient list includes vegetable fats rather than more expensive milk fats. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A hand holding a waffle cone under the nozzle of a machine dispensing pink and white soft serve" src="https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526980/original/file-20230518-2311-9i1j4h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Technically, soft serve isn’t ice cream.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/soft-ice-cream-machine-1312164440">Shutterstock</a></span>
</figcaption>
</figure>
<p>Soft serve products are also formed by agitation as the mixture freezes, but tend to contain less air than ice cream you’d buy in a tub, due to the constant agitation inside the dispensing machine.</p>
<p>Icy poles, ice blocks, freezies, or freeze pops (depending on <a href="https://theconversation.com/togs-or-swimmers-why-australians-use-different-words-to-describe-the-same-things-52007">your local phraseology</a>) and other “water ices” are frozen inside a mould or plastic tubing. The shape of the mould limits the ability to stir the mixture, so the freezing process is typically done “quiescently”, meaning at rest. The crystallisation of the ice is not well controlled, and you may have experienced large crystals that have grown (technically “seeded”) from the popsicle stick.</p>
<p>Humanity has enjoyed ice cream for centuries. It’s a marvellously versatile food with endless variations of flavours, additives, and toppings coupled with memories of happiness, comfort, indulgence and nostalgia. And plenty of chemistry, too.</p><img src="https://counter.theconversation.com/content/205038/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathan Kilah does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It might seem like a simple concept, but to get ice cream right, you need three states of matter and a delicate interplay of chemistry.Nathan Kilah, Senior Lecturer in Chemistry, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2046922023-06-12T20:00:49Z2023-06-12T20:00:49ZDo you need to wash rice before cooking? Here’s the science<figure><img src="https://images.theconversation.com/files/527941/original/file-20230524-21-2zy4a7.jpg?ixlib=rb-1.1.0&rect=242%2C44%2C5595%2C3943&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/jasmine-rice-cooking-electric-cooker-steam-1786700948">Shutterstock</a></span></figcaption></figure><p>Rice is a staple food for billions of people in Asia and Africa. It’s also a versatile ingredient for many iconic dishes from around the world, including dolmades from Greece, risottos from Italy, paella from Spain and rice puddings from the United Kingdom.</p>
<p>Despite its universal appeal, the question asked in every kitchen, be it a professional one or your own home, is whether you should pre-wash (or rinse) your rice before cooking.</p>
<h2>What do chefs and cooks say?</h2>
<p>Culinary experts claim pre-washing rice <a href="https://www.americastestkitchen.com/articles/3946-do-you-really-need-to-rinse-your-rice">reduces the amount of starch</a> coming from the rice grains. You can see this in the cloudy rinse water, which <a href="https://www.sciencedirect.com/science/article/pii/S0924224416300619">studies have shown</a> to be the free starch (amylose) on the surface of the rice grain produced by the milling process. </p>
<p>In culinary circles, washing is advocated for some dishes when a separated grain is sought after. Yet for other dishes such as risottos, paella and rice puddings (where you need a sticky, creamy effect), washing is avoided.</p>
<p>Other factors, such as the type of rice, family tradition, local health warnings and even the perceived time and effort required will influence whether people pre-wash their rice.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of a golden mushroom risotto with flakes of parmesan on top" src="https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/527943/original/file-20230524-19-867jpc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">For risotto, traditionally cooked with arborio rice, rinsing the rice is not recommended, to help enhance the creamy texture of the dish.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/macro-close-small-portion-fungi-risotto-173037734">Shutterstock</a></span>
</figcaption>
</figure>
<h2>Is there evidence that washing rice makes it less sticky?</h2>
<p>A <a href="https://www.sciencedirect.com/science/article/pii/S0308814618313293#b0005">recent study</a> compared the effect of washing on the stickiness and hardness of three different types of rice from the same supplier. The three types were glutinous rice, medium grain rice and jasmine rice. These different rices were either not washed at all, washed three times with water, or washed ten times with water.</p>
<p>Contrary to what chefs will tell you, this study showed the washing process had no effect on the stickiness (or hardness) of the rice. </p>
<p>Instead, the researchers demonstrated the stickiness was not due to the surface starch (amylose), but rather a different starch called amylopectin that is leached out of the rice grain during the cooking process. The amount leached differed between the types of rice grains.</p>
<p>So, it’s the variety of rice – rather than washing – that’s critical to the stickiness. In this study, glutinous rice was the stickiest, while medium grain rice and jasmine rice were less sticky, and also harder as tested in the laboratory. (Hardness is representative of the textures associated with biting and chewing.)</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of a fried rice dish with chicken, vegetables and a sunny side egg on top" src="https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/527944/original/file-20230524-29-eqan30.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fried rice dishes, such as nasi goreng, tend to use less sticky varieties of rice, leading to a more fluffy texture.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fried-rice-nasi-goreng-chicken-egg-759039364">Shutterstock</a></span>
</figcaption>
</figure>
<h2>You may still want to wash your rice, though</h2>
<p>Traditionally rice was washed to rinse off dust, insects, little stones and bits of husk left from the rice hulling process. This may still be important for some regions of the world where the processing is not as meticulous, and may provide peace of mind for others. </p>
<p>More recently, with the heavy use of plastics in the food supply chain, microplastics have been found in our foods, including rice. The washing process has been shown to rinse up to 20% of the plastics <a href="https://www.sciencedirect.com/science/article/pii/S0304389421007421?via%3Dihub">from uncooked rice</a>.</p>
<p>This same study found that irrespective of the packaging (plastic or paper bags) you buy rice in, it contains the same level of microplastics. The researchers also showed plastics in (pre-cooked) instant rice have been found to be fourfold higher than in uncooked rice. If you pre-rinse instant rice, you could reduce plastics by 40%.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/youre-eating-microplastics-in-ways-you-dont-even-realise-97649">You're eating microplastics in ways you don't even realise</a>
</strong>
</em>
</p>
<hr>
<p>Rice is also known to contain relatively high levels of arsenic, due to the crop absorbing more arsenic as it grows. <a href="https://pubmed.ncbi.nlm.nih.gov/23245893/">Washing rice has been shown to remove</a> about 90% of bio-accessible arsenic, but it also rinses out a large amount of other nutrients important for our health, including copper, iron, zinc and vanadium.</p>
<p>For some people, rice offers a small percentage of their daily intake of these nutrients and hence will have a small impact on their health. But for populations that consume large amounts of heavily washed rice daily, it could impact their overall nutrition.</p>
<p><a href="https://pubmed.ncbi.nlm.nih.gov/29363749/">Another study</a> looked at other heavy metals, lead and cadmium, in addition to arsenic; it found that pre-washing decreased levels of all these from between 7–20%. The <a href="https://www.who.int/news-room/fact-sheets/detail/arsenic#:%7E:text=Long%2Dterm%20exposure%20to%20arsenic,increased%20deaths%20in%20young%20adults.">World Health Organization has warned </a> of the risk of arsenic exposure from water and food.</p>
<p>Arsenic levels in rice vary depending on where it’s grown, the cultivars of rice and the ways it is cooked. The best advice remains to pre-wash your rice and ensure you <a href="https://www.eatforhealth.gov.au/guidelines/australian-guide-healthy-eating">consume a variety of grains</a>. The most <a href="https://pubmed.ncbi.nlm.nih.gov/16124284/">recent study in 2005</a> found that the highest level of arsenic was in the United States. However it is important to keep in mind that arsenic is present in <a href="https://www.sciencedirect.com/science/article/pii/S0048969714010614">other foods</a> including products made from rice (cakes, crackers, biscuits and cereals), seaweed, seafood and vegetables.</p>
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<strong>
Read more:
<a href="https://theconversation.com/high-levels-of-cancer-causing-arsenic-in-rice-so-why-isnt-it-regulated-in-our-food-33691">High levels of cancer-causing arsenic in rice – so why isn’t it regulated in our food?</a>
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<h2>Can washing rice prevent bacteria?</h2>
<p>In short, no. Washing rice will have no effect on the bacterial content of the cooked rice, as high cooking temperatures will kill all bacteria present.</p>
<p>What is more concerning is how long you store cooked rice or washed rice at room temperature. Cooking rice does not kill the bacterial spores from a pathogen called <em><a href="https://www.foodstandards.gov.au/consumer/safety/foodborne-illness/Pages/bacillus-cereus-.aspx">Bacillus cereus</a></em>.</p>
<p>If wet rice or cooked rice is kept at room temperature, this can activate the bacterial spores and they begin to grow. These bacteria then produce toxins which can not be deactivated by cooking or re-heating; these toxins can cause severe gastrointestinal disease. So, make sure you avoid keeping washed or cooked rice at room temperature for too long.</p><img src="https://counter.theconversation.com/content/204692/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Evangeline Mantzioris is affiliated with Alliance for Research in Nutrition, Exercise and Activity (ARENA) at the University of South Australia. Evangeline Mantzioris has received funding from the National Health and Medical Research Council, and has been appointed to the National Health and Medical Research Council Dietary Guideline Expert Committee.</span></em></p>Some people swear by it, while others don’t bother. But what does the evidence say about washing rice, and when should you do it?Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, Accredited Practising Dietitian, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2050872023-05-16T14:41:27Z2023-05-16T14:41:27ZHow does food get contaminated? The unsafe habits that kill more than 400,000 people a year<figure><img src="https://images.theconversation.com/files/526039/original/file-20230514-182951-p8iehb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Food-borne illnesses usually present as diarrhoea, vomiting and stomach pains. </span> <span class="attribution"><span class="source">Getty Images</span></span></figcaption></figure><p><em>Unsafe foods, according to the <a href="https://www.who.int/news/item/07-03-2022-world-food-safety-day-2022-theme-highlights-the-role-that-safe-nutritional-food-plays-in-ensuring-human-health">World Health Organization</a> (WHO), contribute to poor health, including impaired growth and development, micro-nutrient deficiencies, noncommunicable and infectious diseases, and mental illness. Globally, one in ten people are affected by food-borne diseases each year. Antonina Mutoro, a nutrition researcher at the African Population and Health Research Center, explains what causes food contamination and how we can lower the risk of disease.</em></p>
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<h2>What is food contamination?</h2>
<p>Access to safe and nutritious food is a basic human right which many do not enjoy, partly because of food contamination. This is defined as the presence of harmful chemicals and microorganisms in food that can cause illness. According to the WHO, food contamination affects about <a href="https://www.who.int/news-room/fact-sheets/detail/food-safety">one in every ten people</a> globally and causes about <a href="https://www.who.int/news-room/fact-sheets/detail/food-safety">420,000 deaths annually</a>. </p>
<p>Food contamination can be:</p>
<ul>
<li><p><strong>physical:</strong> foreign objects in food can potentially cause injury or carry disease-causing microorganisms. Pieces of metal, glass and stones can be choking hazards, or cause cuts or damage to teeth. Hair is another physical contaminant.</p></li>
<li><p><strong>biological:</strong> living organisms in food, including microorganisms (bacteria, viruses and protozoa), pests (weevils, cockroaches and rats) or parasites (worms), can cause disease. </p></li>
<li><p><strong>chemical:</strong> substances like soap residue, pesticide residue and toxins produced by microorganisms such as <a href="https://theconversation.com/what-must-be-done-to-get-toxin-out-of-kenyas-food-supply-127137">aflatoxins</a> can lead to poisoning.</p></li>
</ul>
<h2>What are the most common causes of food contamination?</h2>
<p>The most common cause of food contamination is poor food handling. This includes not washing your hands at the appropriate time – before eating and preparing food, after using the toilet, or after blowing your nose, coughing or sneezing. Using dirty utensils, not washing fruits and vegetables with clean water, and storing raw and cooked food in the same place can also be harmful. Sick people should not handle food. And you should avoid consuming under-cooked foods, particularly meat.</p>
<p>Poor <a href="https://theconversation.com/vegetable-farmers-in-urban-ghana-dont-worry-much-about-food-safety-but-they-should-143706">farming practices</a> can also contaminate food. This includes the heavy use of pesticides and <a href="https://theconversation.com/chickens-from-live-poultry-markets-in-nigeria-could-be-bad-for-your-health-scientists-explain-why-192646">antibiotics</a>, or growing fruits and vegetables using contaminated soil and water. The use of inadequately composted or raw animal manure or sewage is also harmful. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/power-cuts-and-food-safety-how-to-avoid-illness-during-loadshedding-200586">Power cuts and food safety: how to avoid illness during loadshedding </a>
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<p>Fresh foods can lead to a number of illnesses. In Kenya, for instance, the <a href="https://bmcresnotes.biomedcentral.com/articles/10.1186/1756-0500-7-627">contamination of meat</a>, <a href="https://www.researchgate.net/publication/329170819_Consumer_Risk_Exposure_to_Chemical_and_Microbial_Hazards_Through_Consumption_of_Fruits_and_Vegetables_in_Kenya">fruits</a> and <a href="https://pubmed.ncbi.nlm.nih.gov/24968591/">vegetables</a> with human waste is relatively common. This is attributed to the use of contaminated water to wash food. Flies carrying contaminants can also directly transfer faecal matter and bacteria onto plant leaves or fruits.</p>
<p><a href="https://theconversation.com/informal-food-markets-what-it-takes-to-make-them-safer-161601">Street foods</a> are another common source of food contamination. These foods are widely consumed in low- and middle-income countries because they’re cheap and easily accessible. </p>
<h2>What are the signs that you’ve eaten contaminated food?</h2>
<p>Biological and chemical substances are the most common food contaminants. They account for <a href="https://www.who.int/news-room/fact-sheets/detail/food-safety">more than 200 food-borne illnesses</a>, including <a href="https://theconversation.com/explainer-causes-symptoms-and-cures-of-typhoid-fever-53645">typhoid</a>, <a href="https://theconversation.com/explainer-why-cholera-remains-a-public-health-threat-74444">cholera</a> and <a href="https://theconversation.com/what-led-to-worlds-worst-listeriosis-outbreak-in-south-africa-92947">listeriosis</a>. Food-borne illnesses usually present as diarrhoea, vomiting and stomach pains.</p>
<p>In severe cases, food-borne illnesses can lead to neurological disorders, organ failure and even death. It’s therefore advisable to seek immediate medical attention if you begin to experience symptoms like persistent diarrhoea and vomiting after eating or drinking.</p>
<p>Children aged under five are the most vulnerable to food-borne illnesses. They bear <a href="https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001923">40%</a> of the food-borne disease burden. A child’s immune system is still developing and can’t fight off infections as effectively as an adult’s. </p>
<p>In low- and middle-income countries, reduced immunity in children can also occur as a result of malnutrition and frequent exposure to infections due to poor hygiene and sanitation, including a lack of access to safe water and toilets. Additionally, when children are ill, they tend to have poor appetites. This translates to reduced food intake. Coupled with increased nutrient losses through diarrhoea and vomiting, this can lead to a cycle of infection and malnutrition and, in extreme cases, death. </p>
<p>Pregnant women and people with <a href="https://theconversation.com/how-do-i-improve-my-immunity-expert-shares-tips-on-what-to-do-and-what-to-avoid-198537">reduced immunity</a> due to illness or age are equally vulnerable and extra care should, therefore, be taken to prevent food-borne illnesses among these groups.</p>
<h2>What can we do to prevent food contamination?</h2>
<p>Food-borne illnesses also have negative economic impacts, especially in low- and middle-income countries. The World Bank estimates it costs more than <a href="https://www.worldbank.org/en/news/press-release/2018/10/23/food-borne-illnesses-cost-us-110-billion-per-year-in-low-and-middle-income-countries#:%7E:text=The%20total%20productivity%20loss%20associated,estimated%20at%20US%24%2015%20billion.">US$15 billion</a> annually to treat these illnesses in these countries. So it’s important to have preventive strategies in place.</p>
<p>Food contamination can be prevented through simple measures:</p>
<ul>
<li><p>washing your hands at key times (before preparing, serving or eating meals; before feeding children, after using the toilet or after disposing of faeces) </p></li>
<li><p>wearing clean, protective clothing during food preparation </p></li>
<li><p>storing food properly</p></li>
<li><p>washing raw foods with clean water</p></li>
<li><p>keeping raw and cooked foods separate</p></li>
<li><p>using separate utensils for meats and for food meant to be eaten raw. </p></li>
</ul>
<p>Good farming practices, such as the use of clean water and application of approved pesticides in recommended amounts, can help prevent food contamination. </p>
<p>Food vendors also need to be trained on food safety, and provided with clean water and proper sanitation. </p>
<p>As part of the research team at the African Population and Health Research Center, I’m working on the <a href="https://healthyfoodafrica.eu/blog/promoting-access-to-nutritious-food-in-nairobi-urban-poor-settings/">Healthy Food Africa project</a>, which aims to boost food security in urban informal settlements through the promotion of food safety. In Kenya, the project is working closely with the Nairobi county government to develop a food safety training manual targeting street food vendors. This will go a long way towards improving food safety in the city.</p><img src="https://counter.theconversation.com/content/205087/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Antonina Mutoro does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Biological and chemical substances are the most common food contaminants and account for over 200 food-borne illnesses.Antonina Mutoro, Postdoctoral Research Scientist, African Population and Health Research CenterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2030582023-05-02T03:43:47Z2023-05-02T03:43:47ZHere’s why your freezer smells so bad – and what you can do about it<figure><img src="https://images.theconversation.com/files/523344/original/file-20230427-28-gy0qd6.jpg?ixlib=rb-1.1.0&rect=206%2C35%2C2568%2C1742&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">TY Lim/Shutterstock</span></span></figcaption></figure><p>Most people would expect a freezer can keep perishable food fresh and safe from spoilage for many months. Unfortunately, this is not always the case.</p>
<p>Have you ever noticed a funky smell in your freezer? Where does it come from and what can be done to fix the problem?</p>
<h2>Hardy microbes and pungent chemicals</h2>
<p>There are several causes for bad smells coming from your freezer. Typically, the culprits are microbes – bacteria, yeasts and moulds.</p>
<p>Although a freezer dramatically slows down the growth of most common spoilage microbes, some can still thrive if the temperature rises above -18°C (<a href="https://www.foodsafety.asn.au/topic/fridge-freezer-foodsafety/">the recommended freezer temperature</a>). This can happen if there is a power outage for more than a few hours, or if you put something hot straight in the freezer.</p>
<p>Food spills and open containers provide an opportunity for microbes to get to work. It’s also worth noting that many microbes will <a href="https://www.safefood.qld.gov.au/newsroom/food-safety-myths-continued/?keyword=freezing">survive freezing</a> and start growing again once conditions are favourable – for example, if you remove the food, partially thaw it, and return it to the freezer.</p>
<p>Two things happen when food breaks down. First, as microbes start to grow, several pungent chemicals are produced. Second, the fats and flavours that are part of the food itself can and will be released.</p>
<p>These are generally referred to as volatile organic compounds (VOCs). They are the pleasant aromas that we sense when we eat, but VOCs can also be produced by bacteria.</p>
<p>For example, many of us would be familiar with the smells that come from fermentation – a microbial process. When fermenting a food, we intentionally contaminate it with microbes of known characteristics, or provide conditions that favour the growth of desirable microbes and subsequent production of aromatic compounds.</p>
<p>By contrast, uncontrolled food spoilage is problematic, especially when the contaminating microbes can cause disease.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of chopsticks picking up a piece of kimchi from a white bowl" src="https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Kimchi is one of the foods we deliberately allow to be ‘contaminated’ in order to produce the intense flavour.</span>
<span class="attribution"><span class="source">Nungning20/Shutterstock</span></span>
</figcaption>
</figure>
<h2>Freezing changes the food</h2>
<p>It is not only microbial growth that can lead to undesirable odours. There’s a suite of chemical processes happening in the freezer, too.</p>
<p>Freezing causes physical changes to foods, often enhancing their breakdown. Many of us would be familiar with “freezer burn” on meats and other foods, as well as ice crystals on frozen food.</p>
<p>This phenomenon is called “<a href="https://en.wikipedia.org/wiki/Brine_rejection">salt rejection</a>”. Depending on how rapidly something is frozen, salts can sometimes be concentrated, as pure water freezes at a higher temperature than water with things dissolved in it – like sugars and salts. On a large scale, this happens to icebergs in the ocean. As the sea water freezes, salt is removed. Thus, the iceberg is composed of fresh water, and the surrounding sea water becomes a saltier and denser brine.</p>
<p>In a similar way, as water in food freezes, organic molecules are concentrated and expelled. If these are volatile, they move about the freezer and stick to other things. Where they end up depends on what else is around.</p>
<p>Some of the volatiles like water. We call them “hydrophilic” or water loving; those are the ones that will make your food taste bad. Other are more water-hating or “hydrophobic” and they stick to things like silicone ice cube trays, <a href="https://www.nytimes.com/wirecutter/blog/how-to-get-smells-out-of-silicone-kitchenware/">making them go smelly</a>.</p>
<p>Domestic freezers are commonly attached to a refrigerator, and this provides another opportunity for smells to move through the systems. The two units share a single cooling source and airflow channel. If your fridge has foul odours from the food inside (natural or after microbial spoilage), it is very likely they will migrate to your freezer.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/how-colour-coding-your-fridge-can-stop-your-greens-going-to-waste-45703">How colour-coding your fridge can stop your greens going to waste</a>
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<h2>Help, my freezer smells!</h2>
<p>There are some simple steps you can take to stop your freezer from smelling.</p>
<p>First, try to prevent odours from developing in the first place by covering the food. If you place food in an airtight container (glass is best), it will dramatically slow the release of any aromatic compounds produced by bacteria or the food itself. Covered food is also less likely to absorb smells and flavours from other foods around it.</p>
<p>If the smells have already developed, you can eliminate them by following a few simple steps, including a thorough clean.</p>
<ul>
<li><p>Remove all items from the freezer and inspect the foods for any spoilage, freezer burn or unpleasant odours. </p></li>
<li><p>Discard anything that has developed ice crystals and store the rest in a cooler box while attending to the freezer itself. You should also inspect the fridge and discard any bad-smelling foods. </p></li>
<li><p>Once you have removed all items, take out the shelves and clean up spills or crumbs. </p></li>
<li><p>Wipe down all surfaces using warm soapy water or a mix of two tablespoons of baking soda with warm water.</p></li>
<li><p>Wash all the shelves and ice compartments and let them dry completely. </p></li>
</ul>
<p>If the smells are not removed with these simple cleaning steps, the freezer may require a deep clean, which involves turning off the unit and letting it “breathe” for a few days.</p>
<p>Placing some baking soda inside the freezer before adding food can help to absorb any residual odours. For serious smells where crevices or insulation are contaminated, you may need a service technician.</p>
<p>In short, even though we think freezers keep things “fresh”, microbes can still proliferate in there. Make sure to clean your freezer now and then to keep your food safe and healthy.</p><img src="https://counter.theconversation.com/content/203058/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Do your ice taste funny? Is there ‘freezer burn’ on your meat? This is why your freezer probably isn’t as clean as you think – but it only takes a few simple steps to fix it.Enzo Palombo, Professor of Microbiology, Swinburne University of TechnologyRosalie Hocking, Swinburne University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2030962023-04-05T13:53:51Z2023-04-05T13:53:51ZEaster bunnies, cacao beans and pollinating bugs: A basket of 6 essential reads about chocolate<figure><img src="https://images.theconversation.com/files/519391/original/file-20230404-14-reloqo.jpg?ixlib=rb-1.1.0&rect=422%2C0%2C4914%2C3173&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Easter has its bunnies, but chocolate comes out for every holiday.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/chocolate-bunny-family-royalty-free-image/177875356">garytog/iStock via Getty Images Plus</a></span></figcaption></figure><p><a href="https://www.insider.com/surprising-easter-fun-facts-stats-2019-4#as-many-as-91-million-chocolate-bunnies-are-sold-in-the-us-for-easter-annually-8">Tens of millions of chocolate bunnies</a> get sold in the U.S. every Easter. Here are six articles about chocolate from The Conversation’s archive – great reading while you’re nibbling the ears off your own bunny (if you’re one of the <a href="https://www.insider.com/surprising-easter-fun-facts-stats-2019-4#as-many-as-78-of-americans-eat-the-ears-of-their-chocolate-bunny-first-11">three-quarters of Americans who start</a> at the top).</p>
<h2>1. Food scientist on cocoa chemistry</h2>
<p>Chocolate bunnies don’t grow on trees – but cacao pods do. It takes a lot of processing to get from the raw agricultural input to the finished output.</p>
<p>Food scientist <a href="https://scholar.google.com/citations?user=5iZjEckAAAAJ&hl=en&oi=ao">Sheryl Barringer</a> from The Ohio State University wrote about various chemical reactions that are part of the transformation of beans into chocolate. One is the Maillard reaction, the same thing that gives the browned bits on roasted meats or a bread’s golden crust their flavor. <a href="https://theconversation.com/chocolate-chemistry-a-food-scientist-explains-how-the-beloved-treat-gets-its-flavor-texture-and-tricky-reputation-as-an-ingredient-198222">Barringer also explains that weird white stuff</a> – known as bloom – that might appear on your Easter chocolates if they hang around for a while. (Don’t worry, it’s still edible.)</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/chocolate-chemistry-a-food-scientist-explains-how-the-beloved-treat-gets-its-flavor-texture-and-tricky-reputation-as-an-ingredient-198222">Chocolate chemistry – a food scientist explains how the beloved treat gets its flavor, texture and tricky reputation as an ingredient</a>
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<h2>2. Chocolate is a fermented food</h2>
<p>Food science Ph.D. candidate <a href="https://scholar.google.com/citations?user=QjIM6yUAAAAJ&hl=en&oi=ao">Caitlin Clark</a> from Colorado State University focuses her research on the microbes responsible for much of chocolate’s flavor. As a fermented food, chocolate depends on yeast and bacteria to help turn a raw ingredient into the treat you can recognize.</p>
<p>Clark described how the microorganisms that occur naturally in a given geographical location can give high-end chocolates their “terroir” – “<a href="https://theconversation.com/chocolates-secret-ingredient-is-the-fermenting-microbes-that-make-it-taste-so-good-155552">the characteristic flair imparted by a place</a>” you might be more used to thinking about with regard to wine.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/chocolates-secret-ingredient-is-the-fermenting-microbes-that-make-it-taste-so-good-155552">Chocolate's secret ingredient is the fermenting microbes that make it taste so good</a>
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<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cacao pods and flowers on branch tree close up" src="https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tiny flies spread pollen from one cacao tree to another.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/cacao-pods-and-flower-on-branch-royalty-free-image/1165785501">dimarik/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<h2>3. Pollinators are important part of process</h2>
<p>Cacao growers rely on another tiny ally to pollinate their crop. Entomologist <a href="https://scholar.google.com/citations?hl=en&user=qvmWZYwAAAAJ">DeWayne Shoemaker</a> from the University of Tennessee described the mini flies – particularly biting midges and gall midges – that get the job done. “Pollinators must pick up pollen from the male parts of a flower of one tree and deposit it on the female parts of a flower on another tree,” Shoemaker wrote.</p>
<p>But up to <a href="https://theconversation.com/tiny-cacao-flowers-and-fickle-midges-are-part-of-a-pollination-puzzle-that-limits-chocolate-production-154334">90% of cacao flowers don’t get pollinated</a> at all. People can hand-pollinate the little flowers, but it remains a mystery which other insects might do the job in the wild.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/tiny-cacao-flowers-and-fickle-midges-are-part-of-a-pollination-puzzle-that-limits-chocolate-production-154334">Tiny cacao flowers and fickle midges are part of a pollination puzzle that limits chocolate production</a>
</strong>
</em>
</p>
<hr>
<h2>4. Child labor is chocolate’s bitter secret</h2>
<p>Harvesting and processing cacao is labor-intensive. To meet this need, some farmers turn to child labor. Cultural anthropologist <a href="https://scholar.google.com/citations?user=1ErMxzgAAAAJ&hl=en&oi=ao">Robert Ulin</a> from the Rochester Institute of Technology described how the global chocolate industry is tied to inequality via exploitative labor practices.</p>
<p>“The largest chocolate companies signed a protocol in 2001 that <a href="https://theconversation.com/some-chocolate-has-a-dark-side-to-it-child-labor-179271">condemned child labor and childhood slavery</a>,” Ulin wrote. But he noted that consumers may want more information to make sure their purchase power supports “fair labor practices in the chocolate sector.” </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/some-chocolate-has-a-dark-side-to-it-child-labor-179271">Some chocolate has a dark side to it – child labor</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Dog and woman, both with Easter bunny ears on" src="https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Do not share your chocolates with your pooch.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/dog-and-woman-with-costume-and-easter-decorations-royalty-free-image/1359250422">F.J. Jimenez/Moment via Getty Images</a></span>
</figcaption>
</figure>
<h2>5. Not safe for furry family members</h2>
<p>Eating a ton of chocolate is probably not a healthy choice for anyone. But even a little bit of chocolate can be deadly for dogs and cats. </p>
<p>In an article about all kinds of holiday foods that are unsafe for pets, veterinarian and researcher <a href="https://experts.okstate.edu/le.fanucchi">Leticia Fanucchi</a> from Oklahoma State University explained the chemicals in this human delicacy that can cause fatal “<a href="https://theconversation.com/holiday-foods-can-be-toxic-to-pets-a-veterinarian-explains-which-and-what-to-do-if-rover-or-kitty-eats-them-196453">chocolate intoxication</a>.” Don’t delay getting veterinary help if your pet does raid your Easter basket.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/holiday-foods-can-be-toxic-to-pets-a-veterinarian-explains-which-and-what-to-do-if-rover-or-kitty-eats-them-196453">Holiday foods can be toxic to pets – a veterinarian explains which, and what to do if Rover or Kitty eats them</a>
</strong>
</em>
</p>
<hr>
<h2>6. An enslaved chocolatier in colonial America</h2>
<p>An enslaved cook named Caesar, born in 1732, was one of the first chocolatiers in the American colonies. Historical archaeologist <a href="https://berkeley.academia.edu/KelleyFantoDeetz">Kelley Fanto Deetz</a> from the University of California, Berkeley described how Caesar “would have had to <a href="https://theconversation.com/oppression-in-the-kitchen-delight-in-the-dining-room-the-story-of-caesar-an-enslaved-chef-and-chocolatier-in-colonial-virginia-151356">roast the cocoa beans on the open hearth</a>, shell them by hand, grind the nibs on a heated chocolate stone, and then scrape the raw cocoa, add milk or water, cinnamon, nutmeg or vanilla, and serve it piping hot.”</p>
<p>Cocoa was a hot commodity for Virginia’s white elite during this period, when it was a culinary component – along with pineapples, Madeira wine, port, champagne, coffee and sugar – of the Columbian Exchange.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/oppression-in-the-kitchen-delight-in-the-dining-room-the-story-of-caesar-an-enslaved-chef-and-chocolatier-in-colonial-virginia-151356">Oppression in the kitchen, delight in the dining room: The story of Caesar, an enslaved chef and chocolatier in Colonial Virginia</a>
</strong>
</em>
</p>
<hr>
<p><em>Editor’s note: This story is a roundup of articles from The Conversation’s archives.</em></p><img src="https://counter.theconversation.com/content/203096/count.gif" alt="The Conversation" width="1" height="1" />
Two food scientists, an entomologist, an anthropologist, a veterinarian and a historian walk into a bar (of chocolate) and tell bitter and sweet stories of this favorite treat.Maggie Villiger, Senior Science + Technology EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2004282023-03-07T13:43:36Z2023-03-07T13:43:36ZPancakes won’t turn you into a zombie as in HBO’s ‘The Last of Us,’ but fungi in flour have been making people sick for a long time<figure><img src="https://images.theconversation.com/files/513212/original/file-20230302-18-uldpy1.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1198%2C628&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A human fungal zombie from the TV show 'The Last of Us.'</span> <span class="attribution"><a class="source" href="https://imgix.bustle.com/uploads/image/2023/1/20/2c922756-5f33-430d-801b-995eec7dc0d1-the-last-of-us.jpg?w=1200&h=630&fit=crop&crop=faces&fm=jpg">Liane Hentscher/HBO</a></span></figcaption></figure><p>In the HBO series “<a href="https://www.hbo.com/the-last-of-us">The Last of Us</a>,” named after the popular video game of the same name, the flour supplies of the world are contaminated with a fungus called <em>Cordyceps</em>. When people eat pancakes or other foods made with that flour, the fungi grow inside their bodies and turn them into zombies. </p>
<p>As a <a href="https://scholar.google.com/citations?user=5iZjEckAAAAJ&hl=en&oi=ao">food scientist</a>, I study the effect of processing on the quality and safety of fruits and vegetables, including the flour used to make pancakes. While no one is going to turn into a zombie from eating pancakes in real life, flour is often contaminated with fungi that can produce mycotoxins that make people sick. Proper processing and cooking, however, can generally keep you safe. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/uLtkt8BonwM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">‘The Last of Us’ is premised on a pandemic that brings the world to an apocalyptic collapse.</span></figcaption>
</figure>
<h2>How common is fungi in flour?</h2>
<p>People have been eating bread made from wheat for <a href="https://www.bbc.com/news/science-environment-44846874">approximately 14,000 years</a> and cultivating wheat for <a href="https://sustainablefoodtrust.org/news-views/a-brief-history-of-wheat/">at least 10,000 years</a>. In 1882, “<a href="https://doi.org/10.7717%2Fpeerj.12346">drunken bread disease</a>” was first documented in Russia, where people reported dizziness, headache, trembling hands, confusion and vomiting after eating bread. Long before that, Chinese peasants were reporting that eating pinkish wheat – a key sign of infection with a mold called <em>Fusarium</em> – caused them to feel ill. Clearly, fungi have been making people sick for a long time.</p>
<p>Wheat, corn, rice and even fruits and vegetables can be infected with fungi as they grow in the field. In “The Last of Us,” an epidemiologist theorizes that climate change is causing the fungus to mutate so it can infect humans. The unfortunate reality is that fungi have become more of a problem in recent years as <a href="https://doi.org/10.3389/fcimb.2018.00060">warmer temperatures</a> encourage their growth. </p>
<p><a href="https://doi.org/10.1111/jfs.12422">A 2017 study</a> found that over 90% of wheat and corn flour samples in Washington, D.C., contained live fungi, with <em>Aspergillus</em> and <em>Fusarium</em> the predominant types of mold in wheat flour. <em>Fusarium</em> grows on wheat in the field and can cause a common agricultural plant disease called <a href="https://ahdb.org.uk/knowledge-library/fusarium-and-microdochium-in-cereals">fusarium head blight</a>, or scab. </p>
<p>Farmers use <a href="https://open.alberta.ca/publications/fusarium-head-blight-of-barley-and-wheat">multiple techniques</a> to reduce this devastating plant disease, including implementing crop rotation, using resistant varieties and fungicides and minimizing irrigation during flowering. After harvesting, they sort the grains to remove contaminated wheat before grinding them into flour. While sorting removes most of the contaminated wheat, small amounts of fungi can still make it into the flour.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pink wheat stalks infected with fusarium head blight" src="https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Wheat infected with fusarium head blight have a characteristic pink hue.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/fusarium-ear-blight-fusarium-head-blight-fhb-or-royalty-free-image/1358429685">Tomasz Klejdysz/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<h2>Killing microorganisms in flour</h2>
<p>The good news is that most fungi and other microorganisms <a href="https://www.ars.usda.gov/ARSUserFiles/60701000/FoodSafetyPublications/p328.pdf">die at 160-170 degrees Fahrenheit</a> (71-77 degrees Celsius). Pancakes are typically cooked to an internal temperature of <a href="https://www.lafujimama.com/oven-baked-pancake/">190-200 F</a> (88-93 C). Other cakes and breads are cooked to internal temperatures <a href="https://blog.thermoworks.com/bread/baked-good-doneness-temps/">anywhere from 180 to 210 degrees Fahrenheit</a> (82-99 C). So, unlike in “The Last of Us,” as long as you bake or fry your dough, you’ll have killed the fungi.</p>
<p>The problem comes when people eat the flour without cooking it first, such as by consuming raw cookie dough or “licking the bowl clean.” Both raw egg and raw flour can contain microorganisms that make people sick. The microorganisms that public health officials are most worried about are <a href="https://www.cdc.gov/foodsafety/communication/ecoli-and-food-safety.html"><em>E. coli</em></a> and <a href="https://www.cdc.gov/foodsafety/communication/salmonella-food.html"><em>Salmonella</em></a>, dangerous pathogens that can cause severe illness. </p>
<p>Most people don’t realize that the flour they buy at the store is raw flour that still contains live microorganisms. Flour is rarely commercially treated to be safe to eat raw because consumers almost always cook flour-based foods. While consumers can also attempt to heat-treat raw flour at home, <a href="https://ag.purdue.edu/stories/home-kitchen-heat-treated-flour-doesnt-protect-against-foodborne-illnesses-purdue-food-scientist-says/">this isn’t recommended</a> because the flour may not be spread thinly enough to kill all of the microorganisms.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Microscopy image of _Aspergillus_" src="https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Aspergillus</em> is one of the predominant molds found in wheat flour.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/aspergillus-under-the-light-microscopic-view-for-royalty-free-image/1332594729">tonaquatic/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<p>Some fungi and microorganisms can create spores, which are like seeds that help them survive adverse conditions. These spores can survive cooking, drying and freezing. There are even <a href="https://www.smithsonianmag.com/smart-news/bread-was-made-using-4500-year-old-egyptian-yeast-180972842/">4,500-year-old yeast spores</a> that have been reawakened and made into bread. These fungal spores rarely cause serious illness in people, except in those with <a href="https://doi.org/10.1101%2Fcshperspect.a019273">weakened immune systems</a>.</p>
<p><a href="https://doi.org/10.3390%2Fmicroorganisms5030037">Chemicals can be added to food</a> to stop fungal growth. These additives include sorbates, benzoates and propionates. However, you almost never see these additives in flour or pancake mix because fungi can’t grow in a dry powder. The fungi either grew on the wheat in the field or on the bread after it is baked. For that reason, you may see these additives in bread but not in a powdered mix.</p>
<h2>Mycotoxins</h2>
<p>The biggest risk from fungi is not that it will grow inside our bodies, but that it will grow on wheat or other foods and produce <a href="https://doi.org/10.5487%2FTR.2019.35.1.001">chemicals called mycotoxins</a> that can cause severe health problems. When wheat is harvested and ground into flour, mycotoxins can get mixed in. </p>
<p>Unfortunately, while normal cooking can kill the microorganisms, it <a href="https://doi.org/10.5487%2FTR.2019.35.1.001">doesn’t destroy the mycotoxins</a>. Eating mycotoxins can cause problems ranging from hallucinations to vomiting and diarrhea to cancer or death. Some of the <a href="https://doi.org/10.1111/jfs.12422">common mycotoxins</a> found in grain include aflatoxins, deoxynivalenol, ochratoxin A and fumonisin B.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Moldy pastry on a plate" src="https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It might be best to leave that moldy bread alone.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/moldy-inedible-spoiled-food-pasty-with-mold-in-a-royalty-free-image/1167797155">Yulia Naumenko/Moment via Getty Images</a></span>
</figcaption>
</figure>
<p>The oldest known case of mycotoxin poisoning is recorded as a <a href="https://doi.org/10.1021/acs.jafc.6b04494">disease called ergotism</a>. Ergotism was mentioned in the Old Testament and has been reported in Western Europe since A.D. 800. It has even been suggested that the <a href="https://www.vox.com/2015/10/29/9620542/salem-witch-trials-ergotism">Salem witch trials</a> were caused by an outbreak of ergotism that led its victims to hallucinate, though many have disputed this idea. Wheat is <a href="https://doi.org/10.1007/s11356-021-12671-w">less likely</a> than other grains to have dangerous mycotoxins, which is why some have proposed that declining mortality in 18th-century Europe, <a href="https://doi.org/10.1017/s0025727300034116">especially in England</a>, was due to the switch from a rye-based diet to a wheat-based diet.</p>
<p>Ultimately, you don’t need to worry about eating those pancakes. Farmers use many techniques to minimize fungal growth and remove moldy grain, and the government keeps a close eye on mycotoxin levels during crop production and storage. Just make sure you cook your bakery products before eating, and don’t eat anything that has started to mold.</p><img src="https://counter.theconversation.com/content/200428/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sheryl Barringer does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Raw flour at the store still contains live microorganisms. And while cooking can kill the fungi, it doesn’t destroy any illness-causing mycotoxins that might be present.Sheryl Barringer, Professor of Food Science and Technology, The Ohio State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1979932023-02-01T19:12:30Z2023-02-01T19:12:30Z8 everyday foods you might not realise are ultra processed – and how to spot them<figure><img src="https://images.theconversation.com/files/506026/original/file-20230124-21-t9zp4r.jpg?ixlib=rb-1.1.0&rect=44%2C55%2C7304%2C4847&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/african-american-father-cute-hungry-son-695805901">Shutterstock</a></span></figcaption></figure><p>For years, the term “junk food” has been used to refer to foods considered bad for you, and not very nutritious. But junk can mean different things to different people. </p>
<p>Official dietary guidelines have used more palatable terms such as “discretionary foods”, “sometimes foods” and “foods high in sugar, salt and fat”. But these labels haven’t always made the task of identifying nutritious foods much easier. After all, many fresh fruits are high in sugar and some salad vegetables are low in nutrients – but that doesn’t make them unhealthy. And food products such as soft drinks with “no added sugar” and muesli bars fortified with nutrient additives aren’t necessarily healthy.</p>
<p>In 2009, <a href="https://www.cambridge.org/core/journals/public-health-nutrition/article/nutrition-and-health-the-issue-is-not-food-nor-nutrients-so-much-as-processing/0C514FC9DB264538F83D5D34A81BB10A">experts proposed</a> using the extent and purpose of industrial food processing as a key indicator of nutrition problems. </p>
<p>The theory acknowledged some food processing helps make foods more convenient, safer and tastier. But it also nominated a class of foods – called “ultra-processed foods” – as unhealthy, based on more than the content of salt, fat and sugar. </p>
<p>A large body of evidence now shows ultra-processed food consumption is associated with poorer <a href="https://www.mdpi.com/2072-6643/12/7/1955">human health</a> (including rates of heart diseases, diabetes and obesity) and <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4306622">planetary health</a> (plastic pollution, excessive energy and land use, biodiversity loss).</p>
<p>But how can you spot those foods when you’re planning what to buy or eat?</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ultra-processed-foods-are-trashing-our-health-and-the-planet-180115">Ultra-processed foods are trashing our health – and the planet</a>
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<h2>What counts as an ultra-processed food?</h2>
<p>Ultra-processed foods are made using industrial processing methods and contain ingredients you wouldn’t usually find in your home pantry. </p>
<p>Processing methods used may include <a href="http://pubs.cahnrs.wsu.edu/publications/wp-content/uploads/sites/2/publications/FS264E.pdf">extrusion</a>, moulding, chemical modification and hydrogenation (which can turn liquid unsaturated fat into a more solid form). But manufacturers don’t need to state the processes foods undergo on the label, so it can be challenging to identify ultra-processed foods. The best place to start is the ingredients list.</p>
<p>There are two types of ingredients that classify ultra-processed foods: industrial food substances and cosmetic additives. Food substances include processed versions of protein and fibre (such as whey powder or inulin), maltodextrin (an intensely processed carbohydrate), fructose or glucose syrups, and hydrogenated oils. </p>
<p>Cosmetic additives are used to improve the texture, taste or colour of foods. They make ultra-processed foods more attractive and irresistibly tasty (contributing to their over-consumption). Examples are colours and flavours (including those listed as “natural”), non-caloric sweeteners (including stevia), flavour enhancers (such as yeast extract and MSG), and thickeners and emulsifiers (which modify a food’s texture).</p>
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<strong>
Read more:
<a href="https://theconversation.com/ultraprocessed-foods-like-cookies-chips-frozen-meals-and-fast-food-may-contribute-to-cognitive-decline-196560">Ultraprocessed foods – like cookies, chips, frozen meals and fast food – may contribute to cognitive decline</a>
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</em>
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<h2>8 foods you might not realise are ultra-processed</h2>
<p>Ultra-processed is not just another name for junk – although foods like soft drinks, confectionery and chips are ultra-processed. There are many packaged foods we’d normally consider healthy that are ultra-processed. </p>
<p><strong>1. Breakfast cereals</strong></p>
<p>Many cereals and breakfast drinks marketed as healthy are ultra-processed. They can contain maltodextrins, processed proteins and fibres, and colours. Oats, on the other hand, contain just one ingredient: oats! </p>
<p><strong>2. Protein and muesli bars and balls</strong></p>
<p>Despite the healthy hype, many of these are ultra-processed, containing processed fibres and proteins, invert sugars (sugars modified through an industrial process) and non-caloric sweeteners.</p>
<p><strong>3. Plant-based ‘milks’</strong></p>
<p>Many dairy alternatives contain emulsifiers, vegetable gums and flavours. Not all brands are ultra-processed so check the ingredients list. Some soy milks only contain water, soybeans, oil and salt. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="array of different coloured breakfast cereals" src="https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506028/original/file-20230124-11-ydoe2m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Some ultra-processed foods are easy to spot. But others seem healthy enough.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/variety-cold-cereals-quick-breakfast-kids-577772020">Shutterstock</a></span>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/food-and-drinks-are-getting-sweeter-even-if-its-not-all-sugar-its-bad-for-our-health-187605">Food and drinks are getting sweeter. Even if it's not all sugar, it's bad for our health</a>
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<p><strong>4. Breads</strong> </p>
<p>Some packaged breads contain emulsifiers, modified starches (starches altered through industrial methods) and vegetable gums – they’re usually the plastic wrapped, sliced and cheaper breads. Fresh bakery breads, on the other hand, are rarely ultra-processed.</p>
<p><strong>5. Yogurts</strong> </p>
<p>Flavoured yogurts often contain additives like thickeners, non-caloric sweeteners or flavours. Choose plain yogurts instead. </p>
<p><strong>6. Meal bases and sauces</strong></p>
<p>Pre-prepared pasta and stir-fry sauces typically contain ingredients such as thickeners, flavour enhancers and colours. But simple sauces you can make at home with ingredients like canned tomatoes, vegetables, garlic and herbs are minimally processed.</p>
<p><strong>7. Processed meats</strong></p>
<p>Packaged cold meats may have emulsifiers, modified starches, thickeners and added fibres – making them ultra-processed. Replace packaged processed meats with alternatives such as cold roast meats or chicken instead.</p>
<p><strong>8. Margarine</strong></p>
<p>The way margarines and non-dairy spreads are made (by hydrogenating the vegetable oils) and the additives they contain, such as emulsifiers and colours, make them an ultra-processed food – unlike butter, which is essentially cream and some salt.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="man in supermarket looks confused" src="https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=411&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=411&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=411&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=516&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=516&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506032/original/file-20230124-13-yxys4z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=516&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Ultra-processed foods dominate supermarket shelves. But it’s worth checking the ingredients list.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-man-shopping-supermarket-reading-product-1932968393">Shutterstock</a></span>
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</figure>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/misleading-food-labels-contribute-to-babies-and-toddlers-eating-too-much-sugar-3-things-parents-can-do-194168">Misleading food labels contribute to babies and toddlers eating too much sugar. 3 things parents can do</a>
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<hr>
<h2>But are all ultra-processed foods bad?</h2>
<p>Some types of ultra-processed foods may look healthier than others, having fewer industrial ingredients or being lower in sugar. But these are not necessarily less harmful to our health. We know Australians consume up to <a href="https://bmjopen.bmj.com/content/9/8/e029544">42% of their energy</a> from ultra-processed foods and the cumulative effect of industrial ingredients over the whole diet is unknown. </p>
<p>Also, when you consume an ultra-processed food, you may be displacing a nutritious fresh food or dish from your diet. So, reducing ultra-processed foods as much as possible is a way to move to a <a href="https://www.cambridge.org/core/journals/public-health-nutrition/article/ultraprocessed-foods-a-fitforpurpose-concept-for-nutrition-policy-activities-to-tackle-unhealthy-and-unsustainable-diets/1698DBB568B10674ED2D06F1D7373D5A">healthier and more sustainable diet</a>. Though not exhaustive, there are <a href="https://world.openfoodfacts.org/">online databases</a> that rate specific products to guide food choices. </p>
<p>Supermarkets are dominated by ultra-processed foods, so it can be difficult to avoid them entirely. And sometimes choices are limited by <a href="https://theconversation.com/are-you-living-in-a-food-desert-these-maps-suggest-it-can-make-a-big-difference-to-your-health-196477">availability</a>, allergies or dietary intolerance. We can all make positive changes to our diet by choosing less processed foods. But governments can also legislate to make minimally processed foods more available and affordable, while <a href="https://academic.oup.com/cdn/article/6/8/nzac112/6628777">discouraging the purchase and consumption of ultra-processed foods</a>.</p><img src="https://counter.theconversation.com/content/197993/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Lawrence receives funding from the Australian Research Council. He is a Board member of Food Standards Australia New Zealand. The views expressed in this article do not necessarily reflect the positions of any organisation with which he is associated.</span></em></p><p class="fine-print"><em><span>Priscila Machado receives funding from an Alfred Deakin Postdoctoral Research Fellowship provided by Deakin University, and has received funding from the Australian Research Council and Sao Paulo Research Foundation. She is affiliated with Nutrition Society of Australia, the World Public Health Nutrition Association and the Healthy Food Systems Australia advocacy group.</span></em></p><p class="fine-print"><em><span>Julie Woods and Sarah Dickie do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>‘Ultra-processed’ is not just another term for junk food. It has been shown to be bad for the body and the planet – and it can be tricky to identify.Sarah Dickie, PhD Candidate in Public Health Nutrition, Deakin UniversityJulie Woods, Honorary Associate Professor of Public Health Nutrition, Deakin UniversityMark Lawrence, Professor of Public Health Nutrition, Institute for Physical Activity and Nutrition, Deakin UniversityPriscila Machado, Research Fellow, Institute for Physical Activity and Nutrition, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1978972023-01-29T19:09:07Z2023-01-29T19:09:07ZNope, coffee won’t give you extra energy. It’ll just borrow a bit that you’ll pay for later<figure><img src="https://images.theconversation.com/files/505804/original/file-20230123-15-2ygfk7.jpg?ixlib=rb-1.1.0&rect=34%2C34%2C7715%2C5135&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://images.pexels.com/photos/459270/pexels-photo-459270.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=2">Pexels</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Many of us want (or should I say <em>need</em>?) our morning coffee to give us our “get up and go”. Altogether, the people of the world drink more than <a href="https://link.springer.com/article/10.1007/s11906-021-01156-3">two billion cups of coffee each day</a>. </p>
<p>You might think coffee gives you the energy to get through the morning or the day – but coffee might not be giving you as much as you think.</p>
<p>The main stimulant in coffee is the caffeine. And the main way caffeine works is by changing the way the cells in our brain interact with a compound called <a href="https://www.sciencedirect.com/science/article/abs/pii/S1087079207000937">adenosine</a>. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/plunger-espresso-filter-just-because-your-coffee-is-bitter-doesnt-mean-its-stronger-188905">Plunger, espresso, filter? Just because your coffee is bitter, doesn't mean it's 'stronger'</a>
</strong>
</em>
</p>
<hr>
<h2>Getting busy, getting tired</h2>
<p>Adenosine is <a href="https://www.sciencedirect.com/science/article/abs/pii/S1087079201902011">part of the system</a> that regulates our sleep and wake cycle and part of why high levels of activity lead to tiredness. As we go about our days and do things, <a href="https://www.ingentaconnect.com/content/ben/ctmc/2011/00000011/00000008/art00008">levels of adenosine rise</a> because it is released as a by-product as energy is used in our cells. </p>
<p>Eventually <a href="https://www.sciencedirect.com/science/article/abs/pii/S1087079201902011">adenosine binds to its receptor</a> (parts of cells that receive signals) which tells the cells to slow down, making us feel drowsy and sleepy. This is why you feel tired after a big day of activity. While we are sleeping, <a href="https://www.ingentaconnect.com/content/ben/cn/2009/00000007/00000003/art00008">energy use drops</a> lowering adenosine levels as it gets shuffled back into other forms. You wake up in the morning feeling refreshed. Well, if you get enough sleep that is. </p>
<p>If you are still feeling drowsy when you wake up caffeine can help, for a while. It works by binding to the <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1600-0773.1995.Tb00111.X">adenosine receptor</a>, which it can do because it is a similar shape. But it is not so similar that it triggers the drowsy slow-down signal like adenosine does. Instead it just fills the spots and stops the adenosine from binding there. This is what staves off the drowsy feeling. </p>
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<h2>No free ride</h2>
<p>But there is a catch. While it feels energising, this little caffeine intervention is more a loan of the awake feeling, rather than a creation of any new energy. </p>
<p>This is because the <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/j.1471-4159.2007.05196.x">caffeine won’t bind forever</a>, and the adenosine that it blocks doesn’t go away. So eventually the caffeine breaks down, lets go of the receptors and all that adenosine that has been waiting and building up latches on and the drowsy feeling comes back – sometimes all at once. </p>
<p>So, the debt you owe the caffeine always eventually needs to be repaid, and the only real way to repay it is to sleep. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="cups of coffee on table in mug that reads life begins with coffee" src="https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/505803/original/file-20230123-17-uku54t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">But first, coffee.</span>
<span class="attribution"><a class="source" href="https://images.unsplash.com/photo-1504888527749-e68244b4d3d7?ixlib=rb-4.0.3&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=2070&q=80">Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
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<h2>Timing is everything</h2>
<p>How much free adenosine is in your system, that hasn’t attached to receptors yet, and how drowsy you are as a consequence will impact how much the caffeine you drink wakes you up. So, the coffee you drink <a href="https://journals.sagepub.com/doi/abs/10.1177/026988119100500205">later in the day</a>, when you have more drowsy signals your system may feel more powerful. </p>
<p>If it’s too late in the day, caffeine can make it hard to fall asleep at bedtime. The “half life” of caffeine (how long it takes to break down half of it) is about <a href="https://www.ncbi.nlm.nih.gov/books/NBK223808/#:%7E:text=The%20mean%20half%2Dlife%20of,et%20al.%2C%201989">five hours</a>). That said, we all <a href="https://pubmed.ncbi.nlm.nih.gov/29514871/#:%7E:text=The%20pharmacokinetics%20of%20caffeine%20are,enzyme%2C%20N%2Dacetyltransferase%202.">metabolise caffeine</a> differently, so for some of us the effects wear off more quickly. Regular coffee drinkers might feel less of a caffeine “punch”, with <a href="https://pubmed.ncbi.nlm.nih.gov/1888264/">tolerance</a> to the stimulant building up over time.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="cup of coffee next to laptop" src="https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/505805/original/file-20230123-16-egstvh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Coffee drunk late in the day can hit differently.</span>
<span class="attribution"><a class="source" href="https://images.pexels.com/photos/414630/pexels-photo-414630.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=2">Pexels</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Caffeine can also <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2257922/">raise levels of cortisol</a>, a stress hormone that can make you feel more alert. This might mean caffeine feels more effective later in the morning, because you already have a natural rise in cortisol when you wake up. The impact of a coffee right out of bed might not seem as powerful for this reason. </p>
<p>If your caffeinated beverage of choice is also a sugary one, this can exacerbate the peak and crash feeling. Because while sugar does create actual energy in the body, the free sugars in your drink can cause a spike in blood sugar, which can then make you feel tired when the <a href="https://www.mayoclinic.org/diseases-conditions/diabetes/expert-answers/reactive-hypoglycemia/faq-20057778">dip comes afterwards</a>. </p>
<p>While there is no proven harm of drinking coffee on an empty stomach, <a href="https://www.hsph.harvard.edu/nutritionsource/caffeine/#:%7E:text=Food%20or%20food%20components%2C%20such,drank%20it%20while%20eating%20breakfast.">coffee with or after a meal</a> might hit you more slowly. This is because the food might slow down the rate at which the caffeine is absorbed. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/does-coffee-burn-more-fat-during-exercise-what-the-evidence-tells-us-157739">Does coffee burn more fat during exercise? What the evidence tells us</a>
</strong>
</em>
</p>
<hr>
<h2>What about a strong tea or fizzy cola?</h2>
<p>Coffee, of course, isn’t the only caffeinated beverage that can loan you some energy. </p>
<p>The caffeine in tea, energy drinks and other beverages still impacts the body in the same way. But, since the ingredients mostly come from plants, each caffeinated beverage has its own profile of additional compounds which can have their <a href="https://www.sciencedirect.com/science/article/abs/pii/S0195666312000335">own stimulant effect</a>, or can interact with caffeine to change its impacts.</p>
<p>Caffeine can be useful, but it isn’t magic. To create energy and re-energise our bodies we need enough food, water and sleep. </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CnnSc1lvLgC","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p><img src="https://counter.theconversation.com/content/197897/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emma Beckett has received funding for research or consulting from Mars Foods, Nutrition Research Australia, NHMRC, ARC, AMP Foundation, Kellogg, and the University of Newcastle. She is a member of committees/working groups related to nutrition or the Australian Academy of Science, the National Health and Medical Research Council and the Nutrition Society of Australia.</span></em></p>Feeling tired and groggy in the morning may well lead you to crave a coffee boost. But is it a gift or just a loan in terms of energy?Emma Beckett, Senior Lecturer (Food Science and Human Nutrition), School of Environmental and Life Sciences, University of NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1961012023-01-29T14:22:06Z2023-01-29T14:22:06ZHow science and innovation can strengthen global food systems<figure><img src="https://images.theconversation.com/files/506496/original/file-20230125-24-s7cnmg.jpg?ixlib=rb-1.1.0&rect=10%2C191%2C6699%2C4265&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Innovations in food systems, like food processing technologies, have enhanced the sensory quality, safety and shelf life of food products.</span> <span class="attribution"><span class="source">(Scott Warman/Unsplash)</span></span></figcaption></figure><p>Food systems, from production to consumption, are complex in nature and require co-ordinated efforts at different levels. <a href="https://www.unicef.org/stories/food-systems">Food systems</a> are the public policy decisions, the national and global supply chains and the public or private individuals and groups that influence what we eat.</p>
<p>Unfortunately, current <a href="https://www.wfp.org/food-systems">global food systems are not sustainable</a>. <a href="https://www.who.int/news/item/06-07-2022-un-report--global-hunger-numbers-rose-to-as-many-as-828-million-in-2021">One in nine people</a> are affected by hunger globally. This situation was <a href="https://www.who.int/news/item/12-07-2021-un-report-pandemic-year-marked-by-spike-in-world-hunger">worsened by the pandemic</a>.</p>
<p>Global food systems currently do not prevent malnutrition. In fact, they can worsen nutrition and health outcomes with the <a href="https://doi.org/10.1038/s41574-019-0176-8">high rates of obesity</a> and related health issues caused by unhealthy diets. Food today also lacks <a href="https://www.nationalgeographic.co.uk/environment-and-conservation/2022/05/fruits-and-vegetables-are-less-nutritious-than-they-used-to-be">sufficient nutrients</a>.</p>
<p>Food systems affect the environment negatively, contributing about <a href="https://news.un.org/en/story/2021/03/1086822">one-third of global greenhouse gas emissions from 1990–2015</a>. They are <a href="https://www.wfp.org/food-systems">susceptible to disruptions</a> like the pandemic, the <a href="https://news.un.org/en/story/2022/04/1115852">Russia-Ukraine war</a> or any natural disasters. But science and innovation can offer a way out.</p>
<h2>First steps toward scientific innovations</h2>
<p>UN Secretary-General António Guterres convened <a href="https://www.un.org/en/food-systems-summit">the Food Systems Summit in 2021</a> with the goal of encouraging stakeholders to collaborate in making tangible, positive changes to global food systems.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1230856010908172294"}"></div></p>
<p>With five action tracks, the summit focused on efforts towards achieving the <a href="https://sdgs.un.org/goals">UN Sustainable Development Goals</a> related to food systems, especially <a href="https://sdgs.un.org/goals/goal2">Goal 2 (Zero Hunger)</a>.</p>
<p>Before the Summit, an <a href="https://sc-fss2021.org/">independent Scientific Group</a> was set up to provide input from the global scientific community. Information generated was used to recommend <a href="https://sc-fss2021.org/wp-content/uploads/2021/09/ScGroup_Reader_UNFSS2021.pdf">seven innovation priorities</a> for transforming food systems. Three are directly related to food science and technology.</p>
<h2>Innovations in food science and technology</h2>
<p>Innovations in food science and technology are well-positioned to address many food systems challenges. <a href="https://iufost.org/sites/default/files/IUFoST%20SIB%20-%20Food%20Processing-%20Opportunities%20and%20Challenges.pdf">Food processing</a> has enabled nutrient preservation and the enhancement of sensory quality, safety and shelf life of food products. <a href="https://doi.org/10.1016/j.sciaf.2020.e00667">Food fortification</a> — the process of adding micronutrients to food — helps meet specific nutritional needs to mitigate malnutrition.</p>
<p><strong>1) Best out of waste:</strong> </p>
<p>The <a href="https://www.weforum.org/agenda/2021/03/global-food-waste-solutions/">world wastes millions of tonnes of food</a> every year. Reducing food waste and encouraging people to consume diets with lower carbon footprint would therefore be ideal. But since that seems too idealistic, processing technologies (like <a href="https://innovationorigins.com/en/3d-printer-aims-to-cut-down-on-food-waste-in-restaurants-by-reusing-leftovers/">3D printing</a>) can be used to <a href="https://doi.org/10.1007/978-1-4939-1378-7_18">convert this waste into new food products,</a> promoting efficient use of resources.</p>
<figure class="align-center ">
<img alt="A wheat farm with a tractor in the background." src="https://images.theconversation.com/files/506493/original/file-20230125-22-w8vgzl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506493/original/file-20230125-22-w8vgzl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=428&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506493/original/file-20230125-22-w8vgzl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=428&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506493/original/file-20230125-22-w8vgzl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=428&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506493/original/file-20230125-22-w8vgzl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=537&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506493/original/file-20230125-22-w8vgzl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=537&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506493/original/file-20230125-22-w8vgzl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=537&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Diversification can help reduce the overuse of the five big staple foods, including wheat, and widen the type of nutrients consumed.</span>
<span class="attribution"><span class="source">(Scott Butner/flickr)</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p><strong>2) Food diversification:</strong></p>
<p>Ongoing food diversification efforts include untapped resources (like <a href="https://media.un.org/en/asset/k1h/k1h0tqi7qq">millets</a> and baobabs) that have high amounts of nutrients. These neglected, underutilized, minor or orphan crops should be consumed more. Using sustainable alternatives like marine-based foods and <a href="https://www.fao.org/3/i3253e/i3253e.pdf">edible insects</a> is also gaining popularity in some cultures.</p>
<p>Diversification can help reduce the overuse of the five big staples (maize, rice, wheat, potatoes and cassava) and <a href="https://www.bioversityinternational.org/e-library/publications/detail/diversifying-food-and-diets/">widen the type of nutrients consumed</a>. It can also encourage local food production, building resilience.</p>
<p><strong>3) Sustainable food processing:</strong></p>
<p>Food processing such as <a href="https://fermentationassociation.org/evidence-of-fermented-health-benefits/#:%7E:text=">fermentation has proven to unlock the health benefits</a> of food. There is strong scientific evidence that the active components of functional foods — foods that offer health benefits beyond their nutritional value — can <a href="https://doi.org/10.1007/s11886-015-0593-9">prevent diseases</a> like hypertension and Type 2 diabetes.</p>
<p>This preventative approach to health is largely underutilized.</p>
<h2>Effective implementation equals success</h2>
<p>The main task now is to efficiently implement these recommendations, especially in regions most affected by food insecurity.</p>
<p>Food systems policy initiatives mostly occur at the national and <a href="https://www.fao.org/cfs/cfs-hlpe/en">global levels</a>, and community-level engagements can help increase the chances of sustaining their impact locally. Local engagement can also help gather and implement traditional knowledge and cultural beliefs that influence innovation.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/3xHjp_qevbc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Food system solutions need to be locally driven and culturally informed.</span></figcaption>
</figure>
<p>This calls for inclusive approaches in gathering scientific data, including through <a href="https://www.cgiar.org/innovations/seeds-for-needs-citizen-science-and-crowdsourcing/">citizen science</a>. Data sharing in scientific journals should also expand to include unconventional methods and results, especially those of regional importance, that can expedite the solutions.</p>
<p>Interventions also need to be consumer-focused. Emerging innovations should be driven by public participation and input, instead of industry and funding priorities. Food is an emotive topic and involving the public in discussions on food systems can help reduce misinformation and encourage acceptance of innovations.</p>
<p>At the same time, the political will to drive innovation-focussed food systems locally and globally is also crucial. Industry should be required to prioritize innovations that sustainably produce food with direct public benefit. </p>
<p>Increased financial investment is also needed. The UN Food Systems Summit Scientific Group proposed that governments around the world should spend at least <a href="https://knowledge4policy.ec.europa.eu/publication/science-transformation-food-systems-opportunities-un-food-systems-summit_en#:%7E:text=The%20Brief%20proposes%2C%20as%20a%20key%20food%20systems,in%20reaching%20quickly%20the%20equivalent%20of%20this%20target.">one per cent of their agricultural GDP on food systems science and innovation</a>. This support should also be extended for the creation of small businesses and niche markets for unconventional food products, especially in rural communities and low- and middle-income countries.</p>
<p>Lastly, the complexity of food systems today requires the collaboration across different scientific disciplines and sectors when it comes to developing and implementing solutions. Academic and research institutions should therefore update their policies to adequately reward such collaborative approaches that stand a better chance of providing solutions than the status quo.</p><img src="https://counter.theconversation.com/content/196101/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chibuike Udenigwe receives funding from the Natural Sciences and Engineering Research Council of Canada (NSERC). </span></em></p>Innovations in food science and technology are well-positioned to address many existing food systems challenges.Chibuike Udenigwe, Professor and University Research Chair in Food Properties and Nutrient Bioavailability, L’Université d’Ottawa/University of OttawaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1969802023-01-18T12:02:53Z2023-01-18T12:02:53ZIs Veganuary bad for you? A nutritionist explains why plant-based diets need proper planning<figure><img src="https://images.theconversation.com/files/503099/original/file-20230104-129951-wsgy9w.jpg?ixlib=rb-1.1.0&rect=59%2C17%2C3934%2C2634&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/vegetarian-indian-food-dish-rice-ogricami-1024402399">Shutterstock/Dmitry Galaganov</a></span></figcaption></figure><p><a href="https://www.vegansociety.com/get-involved/campaigns/veganuary-2023#:%7E:text=Veganuary%20is%20a%20UK%20non,taking%20part%20worldwide%20in%202021">Veganuary</a> is upon us again, with thousands of people around the world giving up animal products for the month of January. The movement, which encourages people to follow a vegan lifestyle, started in 2014 and has grown rapidly since, with <a href="https://twitter.com/veganuary/status/1490579998419390468">629,000 people</a> from 228 countries taking part in 2022.</p>
<p>When it comes to internet searches, <a href="https://www.statista.com/statistics/1279421/popularity-veganism-countries-worldwide/">figures for 2020</a> show that the UK had the most Google searches for veganism in the world. In 2019, there were <a href="https://www.vegansociety.com/news/media/statistics/worldwide">600,000 vegans in the UK</a>. And, according to the Vegan Society, this number is expected to continue to rise with vegans and vegetarians <a href="https://www.vegansociety.com/news/media/statistics/worldwide">predicted</a> to make up a quarter of the British population by 2025. </p>
<p>Of course, veganism and vegetarianism originated long before westernised veganism became popular. <a href="https://www.livekindly.com/history-veganism-around-world/#:%7E:text=Eight%20via%20Unsplash.-,India,diets%20on%20the%20Indian%20subcontinent.">Vegetarianism</a> was practised as early as the 5th century BC in India, and it is strongly linked with a number of religious traditions worldwide, such as Hinduism, Jainism, Buddhism and Sikhism. And tofu, a well-recognised alternative to meat, originated in China over 2,000 years ago. </p>
<p>When it comes to vegetarianism and <a href="https://doi.org/10.1016/j.clnu.2020.11.035">veganism</a>, the basic principles are similar, both involve eating plant-based food for environmental, ethical, health or religious reasons. But while vegetarians mainly just exclude meat, vegans follow a <a href="https://www.nhsinform.scot/healthy-living/food-and-nutrition/special-diets/vegetarian-and-vegan-diets">much more restrictive diet</a> excluding all animal products as well as any animal-derived foods such as milk, eggs and honey. </p>
<h2>Pros of veganism</h2>
<p>There are several benefits attributed to a vegan diet as long as it is carried out properly. It can help people <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5466943">lose weight</a> and as with a vegetarian diet, has been linked with a reduced risk of <a href="https://doi.org/10.3389%2Ffcvm.2021.756810">heart disease</a> and <a href="https://pubmed.ncbi.nlm.nih.gov/26853923/">certain cancers</a>, such as colon and breast cancer. </p>
<p>A <a href="https://pubmed.ncbi.nlm.nih.gov/33784394/">recent study</a> looking at the effects of a vegan diet in people with or at risk of developing type 2 diabetes, found that a plant-based diet may help to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5466941/">control blood glucose levels</a>. </p>
<figure class="align-center ">
<img alt="Woman eating vegan bowl of salad." src="https://images.theconversation.com/files/503093/original/file-20230104-105030-38d3f6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/503093/original/file-20230104-105030-38d3f6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=360&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503093/original/file-20230104-105030-38d3f6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=360&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503093/original/file-20230104-105030-38d3f6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=360&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503093/original/file-20230104-105030-38d3f6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=452&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503093/original/file-20230104-105030-38d3f6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=452&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503093/original/file-20230104-105030-38d3f6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=452&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Not all vegan diets are created equal.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/healthy-vegetarian-dinner-woman-jeans-warm-1317602774">Shutterstock/Foxys Forest Manufacture</a></span>
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<p>Vegan diets can also be high in iron, although the form of iron from plants is not as “bioavailable” as the iron in meat, which means the body does not absorb it as efficiently as the iron found in animal products. However, this intake can be boosted by combining plant-based iron with <a href="https://gtr.ukri.org/projects?ref=BB%2FL025264%2F1">foods rich in vitamin C</a> – such as oranges, tomatoes and peppers – because vitamin C helps the body absorb iron better.</p>
<h2>And the cons</h2>
<p>On the flip side, becoming a vegan <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6742661/">does not</a> automatically guarantee good health. You could, for example, eat chips for every meal and while you would qualify as a vegan you wouldn’t necessarily be doing your body any favours. Along with the growth in veganism, has come an <a href="https://www.vegansociety.com/news/media/statistics/worldwide">increase in vegan-friendly ready meals</a> - and these have additional salt, sugar and fat to improve their taste. Processed foods commonly include <a href="https://doi.org/10.1136/gutjnl-2016-313099">trans fats and emulsifiers</a> which can harm beneficial gut bacteria. </p>
<p><a href="https://doi.org/10.1371%2Fjournal.pone.0148235">Poorly planned vegan diets</a> may not provide enough niacin, riboflavin (vitamin B2), vitamin D, calcium, iodine, selenium or zinc, all of which are important for <a href="https://www.bbcgoodfood.com/howto/guide/vegan-diet-healthy">maintaining good health</a>. Vegans can be at a greater risk of becoming anaemic because of the lack of <a href="https://doi.org/10.1177%2F1559827616682933">vitamin B12 and omega-3</a>, which can cause fatigue and the inability to concentrate, especially in young people. There is also an association between <a href="https://doi.org/10.1080/10408398.2022.2075311">veganism and lower bone density</a>, which can lead to an increased risk of fractures. </p>
<figure class="align-center ">
<img alt="Vegan junk food pile." src="https://images.theconversation.com/files/503094/original/file-20230104-14-bsxafm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/503094/original/file-20230104-14-bsxafm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503094/original/file-20230104-14-bsxafm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503094/original/file-20230104-14-bsxafm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503094/original/file-20230104-14-bsxafm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503094/original/file-20230104-14-bsxafm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503094/original/file-20230104-14-bsxafm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Just because it’s vegan, doesn’t mean it’s healthy.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/unhealthy-products-food-bad-figure-skin-1062629861">Shutterstock/beats1</a></span>
</figcaption>
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<p>If you did want to change what you’re eating but don’t want to go the vegan way, the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6466433/">Mediterranean diet</a> is classed as one of the healthiest in the world. Think lots of vegetables, fruit, beans, lentils, nuts, olive oil, wholewheat bread, brown rice and fish. This diet does not eliminate meat, but <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6466433/">limits the intake</a>. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/vegan-or-mediterranean-diet-which-is-better-for-heart-health-110052">Vegan or Mediterranean diet – which is better for heart health?</a>
</strong>
</em>
</p>
<hr>
<p>There is <a href="https://pubmed.ncbi.nlm.nih.gov/26471010">growing evidence</a> that following a Mediterranean diet is associated with <a href="https://www.mdpi.com/2072-6643/11/8/1802">good overall health</a> and can help in protection against cardiovascular diseases, diabetes, high blood pressure and obesity. There is also evidence that it has a role in reducing the risk of certain cancers. And it has been linked to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6723598/">a lower risk</a> of cognitive decline and depression. </p>
<h2>What’s right for you</h2>
<p>So to Veganuary or not? While eating less meat, especially processed meat, <a href="https://doi.org/10.3390%2Fantiox8110544">is good for your health</a>, going vegan isn’t the only way to do it. As a nutritionist, I think that rather than fixating on one particular way of eating, it’s better instead to consume a healthy and varied diet.</p>
<p>Indeed, everyone needs to understand what they are eating to ensure a balanced intake, with the correct quantities of protein, carbohydrates, fats, vitamins and minerals. This is especially the case given that diet-related <a href="https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight#:%7E:text=Worldwide%20obesity%20has%20nearly%20tripled,%2C%20and%2013%25%20were%20obese.">health concerns are on the increase</a> around the globe.</p>
<p>So if you are considering taking up Veganuary you need to be aware of the <a href="https://www.mdpi.com/2072-6643/13/11/4144">potential dietary deficiencies</a>. It will also be necessary to take <a href="https://doi.org/10.3238%2Farztebl.2020.0575">supplements</a> such as B12. </p>
<p>Ultimately, veganism is a lifestyle rather than just a diet, so changing to a vegan way of eating requires long-term commitment and planning. It has to be carefully looked into and carried out in an educated way to ensure you are getting all the nutrients needed to maintain a healthy life.</p><img src="https://counter.theconversation.com/content/196980/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hazel Flight does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Taking part in Veganuary? Then you’ll want to read this.Hazel Flight, Programme Lead Nutrition and Health, Edge Hill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1750012022-01-21T11:16:32Z2022-01-21T11:16:32ZWhy you can probably keep milk longer than you think (and why you should)<figure><img src="https://images.theconversation.com/files/441795/original/file-20220120-8856-qfci4n.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C5742%2C3828&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/children-drink-milk-have-fun-kitchen-1049364281">Tetiana Maslovska/Shutterstock</a></span></figcaption></figure><p>Around <a href="https://www.unep.org/thinkeatsave/get-informed/worldwide-food-waste">one-third</a> of the food produced globally every year never gets eaten. This waste often occurs along the supply chain before the food even reaches us. But consumers who throw away food because it’s gone bad, or because they think it may have gone bad, are also responsible for a large proportion of food waste.</p>
<p>All food production results in <a href="https://wrap.org.uk/media-centre/press-releases/food-and-drink-greenhouse-gas-emissions-must-be-key-priority-cop26-says">greenhouse gas emissions</a>. So wasting food is not only bad for your pocket – it’s also bad for the environment.</p>
<p>Recently, <a href="https://www.bbc.co.uk/news/business-59928650">Morrisons supermarket</a> announced that it will move from putting “use by” to “best before” dates on milk. It says this could save seven million pints of its own-brand milk from being wasted each year.</p>
<p>According to British charity <a href="https://wrap.org.uk/media-centre/press-releases/wrap-comes-winning-formula-tackle-milk-waste-0">WRAP</a>, milk is the third most wasted food item in the home (after potatoes and bread) with more than 490 million pints thrown away in the UK annually. So changing the advice to encourage people to keep their milk for longer is likely to be good for the planet. But is this move safe for consumers? The short answer is yes.</p>
<p>First, let’s look at <a href="https://www.food.gov.uk/safety-hygiene/best-before-and-use-by-dates">the terms</a> “use by” and “best before”, which have long <a href="https://doi.org/10.1007/s12351-017-0352-3">confused consumers</a>.</p>
<p>“Use by” is the date until which the manufacturers know the product will remain safe. This is based on scientific analysis which has determined how long a product can be stored before there’s a risk that any dangerous microbes could reach levels that will cause harm. You’ll see use-by dates on foods that can pose a danger if they’re stored too long, such as cooked meats and dairy products.</p>
<p>“Best before” relates to the quality of the product. This date tells you how long you can keep something before the product starts to taste less fresh, or decline in quality (for example, how long you can store bread before it gets a bit stale). But this doesn’t mean the product isn’t safe to eat after this date. You’re likely to see best-before dates on preserved products, such as tinned or frozen foods, which you can safely keep for a long time.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-type-of-milk-is-best-the-answer-is-follow-your-tastebuds-88610">What type of milk is best? The answer is follow your tastebuds</a>
</strong>
</em>
</p>
<hr>
<h2>What about milk?</h2>
<p>You might think milk should sit firmly in the “use by” category – it is a dairy product after all. But actually, shifting to a best-before date is safe for consumers, thanks to a process called pasteurisation. During <a href="https://www.dairycouncil.co.uk/consumers/industry/what-is-pasteurisation">pasteurisation</a>, the milk is heated for a short time to a high temperature. This kills bacteria which can be present in raw milk and cause infections in humans (often called “pathogens”).</p>
<p>Although the pathogens are killed in this process, some non-harmful microbes <a href="https://doi.org/10.1002/9781119237860.ch19">remain</a> in pasteurised milk. So milk is stored at a low temperature (in the fridge) to slow the growth of these remaining microbes. Nonetheless, they will still grow, and it’s the growth of these non-harmful bacteria that cause the milk to spoil. As the microbes grow they produce enzymes to help them break down the milk, which causes the milk to curdle and produces the “off” smell we associate with spoiled milk. </p>
<p>Notably, for pasteurised milk (and we need to be very clear that this ONLY applies to pasteurised milk) even when the milk starts to go off, there’s no evidence the microbes growing in the milk will cause you any serious harm. If you drink a significant amount of spoiled milk, you might find yourself with <a href="https://missouripoisoncenter.org/spoiled-milk/">an upset stomach</a> but there’s nothing to suggest spoiled milk causes infections or severe illness.</p>
<figure class="align-center ">
<img alt="A hand pours a bottle of milk down the sink." src="https://images.theconversation.com/files/441801/original/file-20220120-9266-269nkb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/441801/original/file-20220120-9266-269nkb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/441801/original/file-20220120-9266-269nkb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/441801/original/file-20220120-9266-269nkb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/441801/original/file-20220120-9266-269nkb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/441801/original/file-20220120-9266-269nkb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/441801/original/file-20220120-9266-269nkb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Milk represents a large proportion of food waste.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/hand-pouring-milk-into-kitchen-sink-2075727952">victoras/Shutterstock</a></span>
</figcaption>
</figure>
<p>The best-before date is the manufacturers’ best estimate of how long the milk should last in the fridge before you can detect any spoilage, either by smell, taste or both. Every batch of pasteurised milk is different and will have more or less of these non-harmful bacteria remaining in it, so in reality the best-before date is an estimate of when the milk with the most bacteria left in it will spoil. But many batches of milk will be fine for much longer than this – hence Morrisons’ change in advice.</p>
<h2>The sniff test</h2>
<p>Morrisons have advised using the “<a href="https://www.bbc.co.uk/news/business-59928650">sniff test</a>” to see if the milk is safe to use. This is sensible advice. If there is no detectable evidence of spoilage, the milk is safe to drink. </p>
<p>If you’ve lost your sense of smell, or don’t fancy sniffing the milk, simply pour some into a cup of boiling water as if you were making a cup of tea. If it curdles then it’s started to turn; if it mixes in normally it’s fine to use.</p>
<p>Should you throw milk away if its started to spoil? If you’re just using it for drinking, it’s probably not going to taste too good. But milk that’s starting to turn can be safely used as a substitute for buttermilk, yogurt or sour cream in recipes like rice pudding, pancakes and scones, or can be used to make cheese sauces.</p>
<p>Clearly if the milk has really spoiled (if it’s fully separated, cheesy and slimy), it should be thrown away.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-virtual-reality-training-could-reduce-your-chance-of-food-poisoning-95195">How virtual reality training could reduce your chance of food poisoning</a>
</strong>
</em>
</p>
<hr>
<p>Once again, this advice applies only to pasteurised milk. Raw milk can still contain pathogens and should never be consumed beyond the use-by date. </p>
<p>Also, because different foods naturally contain different types of microbes, this advice cannot be generalised. In other kinds of foods pathogens can reach dangerous levels without any real detectable evidence of spoilage. So generally, the advice is to stick to the use-by date. </p>
<p>But when it comes to pasteurised milk, we can balance expiry dates with our common sense, and reduce the impact of food waste on the planet.</p><img src="https://counter.theconversation.com/content/175001/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cath Rees does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>UK supermarket chain Morrisons recently announced it will use ‘best before’ instead of ‘use by’ dates on its milks. This change makes sense for the environment, and from a food safety perspective too.Cath Rees, Professor of Microbiology, Faculty of Science, Sutton Bonington Campus, University of NottinghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1725712022-01-05T13:45:41Z2022-01-05T13:45:41ZWhat’s the difference between sugar, other natural sweeteners and artificial sweeteners? A food chemist explains sweet science<figure><img src="https://images.theconversation.com/files/438548/original/file-20211220-15-4utuse.jpg?ixlib=rb-1.1.0&rect=349%2C445%2C4427%2C2663&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sugar is just one of many flavor enhancers people and companies use to sweeten foods and beverages.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/food-service-tray-with-sugar-packets-salt-and-royalty-free-image/1000353706?adppopup=true">Marie LaFauci/Moment via Getty Images</a></span></figcaption></figure><p>A quick walk down the drink aisle of any corner store reveals the incredible ingenuity of food scientists in search of sweet flavors. In some drinks you’ll find sugar. A diet soda might have an artificial or natural low-calorie sweetener. And found in nearly everything else is high fructose corn syrup, the king of U.S. sweetness.</p>
<p>I am a <a href="https://chemistry.richmond.edu/faculty/knolin/">chemist who studies compounds found in nature</a>, and I am also a lover of food. With confusing food labels claiming foods and beverages to be diet, zero-sugar or with “no artificial sweeteners,” it can be confusing to know exactly what you are consuming.</p>
<p>So what are these sweet molecules? How can cane sugar and artificial sweeteners produce such similar flavors? First, it is helpful to understand how taste buds work.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two girls licking lollipops." src="https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/438556/original/file-20211220-50043-nhxa2s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You perceive sweet flavors when certain molecules bind to the taste buds on your tongue.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/two-girls-eating-lollipops-outdoors-royalty-free-image/724286183?adppopup=true">Bomin Jeong/EyeEm via Getty Images</a></span>
</figcaption>
</figure>
<h2>Taste buds and chemistry</h2>
<p>The “<a href="https://theconversation.com/that-neat-and-tidy-map-of-tastes-on-the-tongue-you-learned-in-school-is-all-wrong-44217">taste map</a>” – the idea that you taste different flavors on different parts of your tongue – is far from the truth. People are able to taste all flavors anywhere there are taste buds. So what’s a taste bud?</p>
<p>Taste buds are areas on your tongue that contain dozens of taste <a href="http://www.vivo.colostate.edu/hbooks/pathphys/digestion/pregastric/taste.html">receptor cells</a>. These cells can detect the five flavors – sweet, sour, salty, bitter and umami. When you eat, food molecules are dissolved in saliva and then washed across the taste buds, where they bind to the different taste receptor cells. Only molecules with certain shapes can bind to certain receptors, and this produces the perception of different flavors. </p>
<p>Molecules that taste sweet bind to specific proteins on the taste receptor cells called <a href="https://teachmephysiology.com/biochemistry/molecules-and-signalling/g-protein/">G-proteins</a>. When a molecule binds these G-proteins, it triggers a series of signals that are sent to the brain where it is interpreted as sweet. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram of a glucose molucule." src="https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=649&fit=crop&dpr=1 600w, https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=649&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=649&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=815&fit=crop&dpr=1 754w, https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=815&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/438560/original/file-20211220-23354-1etdb6b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=815&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Glucose is the simplest of sugars and is a circle of carbon atoms with oxygen and hydrogen atoms attached to the ring.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Alpha-D-Glucopyranose.svg#/media/File:Alpha-D-Glucopyranose.svg">NEUROtiker/WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>Natural sugars</h2>
<p>Natural sugars are types of carbohydrates known as <a href="https://www.biologyonline.com/dictionary/saccharide">saccharides</a> that are made of carbon, oxygen and hydrogen. You can imagine sugars as rings of carbon atoms with pairs of oxygen and hydrogen attached to the outside of the rings. The oxygen and hydrogen groups are what make sugar sticky to the touch. They behave like Velcro, sticking to the oxygen and hydrogen pairs on other sugar molecules.</p>
<p>The simplest sugars are single-molecule sugars called monosaccharides. You’ve probably heard of some of these. Glucose is the most basic sugar and is mostly made by plants. <a href="https://foodinsight.org/what-is-fructose/">Fructose</a> is a sugar from fruit. <a href="https://chem.libretexts.org/Bookshelves/Biological_Chemistry/Supplemental_Modules_(Biological_Chemistry)/Carbohydrates/Monosaccharides/Galactose">Galactose</a> is a sugar in milk. </p>
<p>Table sugar – or <a href="https://www.sugar.org/sugar/what-is-sugar/">sucrose</a>, which comes from sugar cane – is an example of a dissacharide, a compound made of two <a href="https://www.biologyonline.com/dictionary/monosaccharide">monosaccharides</a>. Sucrose is formed when a <a href="https://sphweb.bumc.bu.edu/otlt/mph-modules/ph/ph709_basiccellbiology/PH709_BasicCellBIology3.html">glucose molecule</a> and a <a href="https://sphweb.bumc.bu.edu/otlt/mph-modules/ph/ph709_basiccellbiology/PH709_BasicCellBIology3.html">fructose molecule</a> join together. Other common dissacharides are lactose from milk and maltose, which comes grains.</p>
<p>When these sugars are eaten, the body processes each of them slightly differently. But eventually they are broken down into molecules that your body converts into energy. The amount of energy from sugar – and all food – is measured in calories.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An aisle of soda." src="https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/438557/original/file-20211220-15-88xiit.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">High fructose corn syrup is the main sweetener for many processed foods and drinks.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/sanibel-island-jerrys-foods-grocery-store-soda-aisle-news-photo/1189380097?adppopup=true">Jeff Greenberg/Universal Images Group via Getty Images</a></span>
</figcaption>
</figure>
<h2>High fructose corn syrup</h2>
<p>High fructose corn syrup is a staple of U.S. foods, and this hybrid sugar sweetener needs a category all on its own. <a href="https://foodinsight.org/what-is-high-fructose-corn-syrup/">High fructose corn syrup</a> is made from corn starch – the main carbohydrate found in corn. Corn starch is made of <a href="http://www.vivo.colostate.edu/hbooks/pathphys/digestion/basics/polysac.html">thousands of glucose molecules</a> bonded together. At an industrial scale, the starch is broken into individual glucose molecules using <a href="https://www.fda.gov/food/food-additives-petitions/high-fructose-corn-syrup-questions-and-answers">enzymes</a>. This glucose is then treated with a second enzyme to convert some of it into fructose. Generally, high fructose corn syrup is roughly <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/high-fructose-corn-syrup">42%-55% fructose</a>.</p>
<p>This blend is sweet and cheap to produce but has a high calorie content. As with other natural sugars, <a href="https://theconversation.com/sugar-isnt-just-empty-fattening-calories-its-making-us-sick-49788">too much high fructose corn syrup is bad for your health</a>. And since most processed foods and drinks are packed full of the stuff, it is easy to consume too much. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A small green plant in a pot." src="https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=790&fit=crop&dpr=1 600w, https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=790&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=790&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=993&fit=crop&dpr=1 754w, https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=993&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/438561/original/file-20211220-23354-o8hpsb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=993&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A chemical in the stevia plant also produces sweet flavors.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Stevia_rebaudiana_(potted_plant).jpg#/media/File:Stevia_rebaudiana_(potted_plant).jpg">Gabriela F. Ruellan/WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>Natural nonsugar sweeteners</h2>
<p>The second category of sweeteners could be defined as natural nonsugar sweeteners. These are food additives such as stevia and monk fruit, as well as natural sugar alcohols. These molecules aren’t sugars, but they can still bind to the sweet receptors and therefore taste sweet.</p>
<p><a href="https://dx.doi.org/10.1097%2FNT.0000000000000094">Stevia</a> is a molecule that comes from the leaves of the <em>Stevia redaudiana</em> plant. It contains “sweet” molecules that are much larger than most sugars and have three glucose molecules attached to them. These molecules are 30 to 150 times sweeter than glucose itself. The sweet molecules from monk fruit are similar to stevia and 250 times sweeter than glucose. </p>
<p>The human body has a really hard time breaking down both stevia and monk fruit. So even though they’re both really sweet, you don’t get any calories from eating them.</p>
<p><a href="https://www.ynhh.org/services/nutrition/sugar-alcohol.aspx">Sugar alcohols</a>, like sorbital, for example, are not as sweet as sucrose. They can be found in a variety of foods, including pineapples, mushrooms, carrots and seaweed, and are often added to diet drinks, sugar-free chewing gum and many other foods and drinks. Sugar alcohols are made of chains of carbon atoms instead of circles like normal sugars. While they are composed of the same atoms as the sugars, sugar alcohols are not absorbed well by the body so they are considered low-calorie sweeteners.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Packets of Splenda, Sweet'N Low and Equal." src="https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=237&fit=crop&dpr=1 600w, https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=237&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=237&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=298&fit=crop&dpr=1 754w, https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=298&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/438555/original/file-20211220-50538-tkxi4f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=298&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chemists have developed a number of lab-made chemicals that taste sweet and are sold as no-sugar sweeteners.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:No-Calorie-Sweetener-Packets.jpg#/media/File:No-Calorie-Sweetener-Packets.jpg">Evan Amos/WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>Artificial sweeteners</h2>
<p>The third way to make something sweet is to add <a href="https://dx.doi.org/10.1007%2Fs13197-011-0571-1">artificial sweeteners</a>. These chemicals are produced in labs and factories and are not found in nature. Like all things that taste sweet, they do so because they can bind to certain receptors in taste buds. </p>
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<p>So far, the U.S. Food and Drug Administration has <a href="https://www.fda.gov/food/food-additives-petitions/additional-information-about-high-intensity-sweeteners-permitted-use-food-united-states">approved six artificial sweeteners</a>. The most well known are probably saccharin, aspartame and sucralose – better known as Splenda. Artificial sweeteners all have different chemical formulas. Some resemble natural sugars while others are radically different. They are usually many times sweeter than sugar – saccharin is an incredible 200 to 700 times sweeter than table sugar – and some of them are hard for the body to break down.</p>
<p>While a sweet dessert may be a simple pleasure for many, the chemistry of how your taste buds perceive sweetness is not so simple. Only molecules with the perfect combination of atoms taste sweet, but bodies deal with each of these molecules differently when it comes to calories. </p>
<p></p><hr> <p></p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/439239/original/file-20220103-48418-1p7tcpi.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/439239/original/file-20220103-48418-1p7tcpi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/439239/original/file-20220103-48418-1p7tcpi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/439239/original/file-20220103-48418-1p7tcpi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/439239/original/file-20220103-48418-1p7tcpi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/439239/original/file-20220103-48418-1p7tcpi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/439239/original/file-20220103-48418-1p7tcpi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em>This article is part of a series examining sugar’s effects on human health and culture. <a href="https://theconversation.com/us/topics/sugar-2022-114641">You can read the articles on theconversation.com.</a></em></p><img src="https://counter.theconversation.com/content/172571/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kristine Nolin does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Just because something is sweet doesn’t necessarily mean it is sugary. There are a number of molecules that taste sweet. To understand how and why takes a little bit of chemistry.Kristine Nolin, Associate Professor of Chemistry, University of RichmondLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1689332021-11-18T19:04:57Z2021-11-18T19:04:57ZWhy do frozen turkeys explode when deep-fried?<figure><img src="https://images.theconversation.com/files/432462/original/file-20211117-13-5nshe4.jpg?ixlib=rb-1.1.0&rect=59%2C28%2C2018%2C1468&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">When water and boiling oil mix, the result can be explosive, as seen in this demonstration. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/usnavy/8079878079/in/photolist-McRqQ-HHdBLe-Bxf4p1-4YCHSd-diZufK-xhntVK-bycty1-7SnvAX-9eF95P-7NU1Fi-2mGKFih-2mGJxss-x5Fm8h-mpERr-2csv5hB-eVFEF1-4rMvha-fuewk5-xhDwbV-6qG4x6-8DHELF-ouWu47-8DHF7z-8DHEWB-8DHEBH-8jBrLf-oydjbv-2iqxCJJ-ovR1jw-BGxu7E-UYEQWE-hKfbQu-4cpxGc-qsDoYN-hKfbEj-oBQZ4Z-oDSzXz-oB2npk-MzmzYq-4DjUjT">U.S. Navy photo by Mass Communication Specialist 2nd Class Travis Alston/Released via Flickr</a></span></figcaption></figure><p>Deep-frying a turkey is a great way to get a delicious, moist meal for Thanksgiving. But this method of cooking can be a very dangerous undertaking. </p>
<p>Every fall, millions of dollars of damage, trips to the ER and <a href="https://www.fdnysmart.org/deep-fryer-fires/">even deaths result from attempts to deep-fry turkeys</a>. The vast majority of these accidents happen because people put frozen turkeys into <a href="https://www.nfpa.org/Public-Education/Fire-causes-and-risks/Seasonal-fire-causes/Thanksgiving">boiling oil</a>. If you are considering deep-frying this year, do not forget to thaw and dry your turkey before placing it in the pot. Failure to do so may lead to an explosive disaster.</p>
<p>What is so dangerous about putting even a partially frozen turkey in a deep-fryer? </p>
<p><a href="https://chemistry.richmond.edu/faculty/knolin/">I am a chemist</a> who studies plant, fungal and animal compounds and have a love of food chemistry. The reason frozen turkeys explode, at its core, has to do with differences in density. There is a difference in density between oil and water and differences in the density of water between its solid, liquid and gas states. When these density differences interact in just the right way, you get an explosion. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A cup filled with a layer of oil sitting on top of a layer of water." src="https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432464/original/file-20211117-23-19ahosy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">If water and oil are in the same container, the denser water will sink to the bottom.</span>
<span class="attribution"><span class="source">Daniel Merino</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Understanding density</h2>
<p>Density is how much an object weighs given a specific volume. For example, imagine you held an ice cube in one hand and a marshmallow in the other. While they are roughly the same size, the ice cube is heavier: It is more dense. </p>
<p>The first important density difference when it comes to frying is that <a href="https://www.engineeringtoolbox.com/liquids-densities-d_743.html">water is more dense than oil</a>. This has to do with how tightly the molecules of each substance pack together and how heavy the atoms are that make up each liquid.</p>
<p>Water molecules are small and pack tightly together. Oil molecules are much larger and don’t pack together as well by comparison. Additionally, water is composed of oxygen and hydrogen atoms, while <a href="https://doi.org/10.1007/978-1-4684-6876-2_2">oils are predominantly carbon and hydrogen</a>. Oxygen is heavier than carbon. This means that, for example, one cup of water has more atoms than one cup of oil, and those individuals atoms are heavier. This is why oil floats on top of water. It is less dense. </p>
<p>While different materials have different densities, liquids, solids and gases of a single material can have different densities as well. You observe this every time you place an ice cube in a glass of water: The ice floats to the top because it is <a href="https://www.usgs.gov/special-topic/water-science-school/science/water-density?qt-science_center_objects=0#qt-science_center_objects">less dense than water</a>. </p>
<p>When water absorbs heat, it changes to its gas phase, steam. Steam occupies <a href="https://www.reference.com/science/ratio-water-steam-e8765e4e16144993">1,700 times</a> the volume as the same number of liquid water molecules. You observe this effect when you boil water in a tea kettle. The force of expanding gas pushes steam out of the <a href="https://phys.org/news/2013-10-kettle.html">kettle through the whistle</a>, causing the squealing noise.</p>
<h2>Frozen turkeys are filled with water</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man in a fire suit placing a turkey in a fryer." src="https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432465/original/file-20211117-21-nqg2mu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Deep-frying a turkey can be safe as long as the turkey is thawed and dried.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/deep-frying-turkey-in-hot-oil-for-christmas-and-royalty-free-image/476495630?adppopup=true">YinYang/E+ via Getty Images</a></span>
</figcaption>
</figure>
<p>Frozen turkeys – or any kind of frozen meats, for that matter – contain a lot of ice. Raw meat can be anywhere from <a href="https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/water-meat-poultry">56% to 73% water</a>. If you have ever thawed a frozen piece of meat, you have probably seen all the liquid that comes out.</p>
<p>For deep-frying, cooking oil is heated to around <a href="https://www.cooksillustrated.com/how_tos/6520-deep-frying-101-treating-your-oil-right">350 degrees Fahrenheit (175 C)</a>. This is much hotter than the boiling point of water, which is 212 F (100 C). So when the ice in a frozen turkey comes in contact with the hot oil, the surface ice quickly turns to steam.</p>
<p>This quick transition is not a problem when it happens at the very surface of the oil. The steam escapes harmlessly into the air. </p>
<p>However, when you submerge a turkey into the oil, the ice inside the turkey absorbs the heat and melts, forming liquid water. Here is where the density comes into play.</p>
<p>This liquid water is more dense than the oil, so it falls the bottom of the pot. The water molecules continue to absorb heat and energy and eventually they change phases and become steam. The water molecules then rapidly spread far apart from one another and the <a href="https://www.reference.com/science/ratio-water-steam-e8765e4e16144993">volume expands by 1,700 times</a>. This expansion causes the density of the water to drop to a <a href="https://www.engineeringtoolbox.com/saturated-steam-properties-d_457.html">fraction of a percent of the density of the oil</a>, so the gas wants to quickly rise to the surface. </p>
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<p>Combine the fast change in density together with the expansion of volume and you get an explosion. The steam expands and rises, blowing the boiling oil out the pot. If that weren’t dangerous enough, as the displaced oil comes into contact with a burner or flame, it can catch fire. Once some droplets of oil catch on fire, the flames will quickly ignite nearby oil molecules, resulting in a fast-moving and often catastrophic fire.</p>
<p>Every year, thousands of accidents like this happen. So, should you decide to deep-fry a turkey for this year’s Thanksgiving, be sure to thoroughly thaw it and pat it dry. And next time you add a bit of liquid to an oil-filled pan and end up with oil all over the stove, you’ll know the science of why.</p><img src="https://counter.theconversation.com/content/168933/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kristine Nolin does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Deep-fried turkeys are delicious, but making one can be dangerous. The scientific reason for fiery Thanksgiving mishaps? A difference in the densities of ice, water and oil.Kristine Nolin, Associate Professor of Chemistry, University of RichmondLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1649892021-08-16T12:09:56Z2021-08-16T12:09:56Z‘Freezer burn’ is a serious problem – preventing ice recrystallization may alleviate it<figure><img src="https://images.theconversation.com/files/416076/original/file-20210813-14-1pzlul3.jpg?ixlib=rb-1.1.0&rect=4%2C51%2C2864%2C1823&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Americans throw away around $5.89 billion worth of frozen food a year.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/freezer-royalty-free-image/170107646">E+ via Getty Images</a></span></figcaption></figure><p>Open the freezer door and there, way in the back, may be an old carton of ice cream growing spikes of ice. Or a forgotten frozen lasagna covered in icy crystals. Or drying of meat surfaces if not well covered. </p>
<p>People sometimes call this phenomenon <a href="https://www.healthline.com/nutrition/freezer-burn#causes">“freezer burn,”</a> and it happens when tiny ice crystals on the food’s surface evaporate directly into vapor without first going through the liquid water phase – a process scientifically termed sublimation. <a href="https://www.loc.gov/everyday-mysteries/food-and-nutrition/item/what-is-freezer-burn/">This moisture loss</a> can leave the food’s surface layers dried out and discolored. </p>
<p>As a <a href="https://scholar.google.com/citations?user=FwENCGEAAAAJ&hl=en">food scientist, I</a> call the initial surface ice formation “ice recrystallization” and study ways to slow it down.</p>
<p>Ice recrystallization damages and destroys organic cells – the smallest living units found in animals and plants. It is just as much a problem when storing harvested food crops or biomedical research materials – like cell cultures – as it is for storing frozen pizza or peas, and can lead to a lot of waste. </p>
<p>There are <a href="https://doi.org/10.1038/s41467-021-21717-z">artificial substances that prevent</a> this kind of ice damage, but few of them are safe to eat. So along with fellow University of Tennessee and Oak Ridge National Laboratory scientists, I’m working for the next three years under <a href="https://www.eurekalert.org/news-releases/878326">a $550,000 grant from the National Science Foundation</a> to identify safe “bio-based” options – materials already found in nature, including substances derived from the natural human digestion process when food is consumed.</p>
<h2>How does ice recrystallization happen?</h2>
<p>The food industry uses “blast freezing” to avoid formation of large ice crystals in frozen food. This process involves exposing foods very quickly to a low temperature and a high rate of air movement, which causes the food to freeze into a mass of numerous small crystals. Small crystals are much less damaging to frozen matter than large ones.</p>
<p>The problem starts after these foods are moved to regular freezers for storage, including home freezers. The automatic defrost function in such units involves turning the compressor on and off several times a day, lowering and raising the temperature to prevent ice buildup. This fluctuation partially melts the ice in the food and then re-freezes it, a process that may create larger and more damaging ice crystals.</p>
<p>These changes can make food at best unpalatable – who hasn’t endured eating freezer-burned vegetables or a watery, thawed strawberry? – and at worst unusable.</p>
<p>According to <a href="https://doi.org/10.1186/s12937-020-00552-w">a recent study</a> by College of William & Mary food system researcher <a href="https://www.wm.edu/as/kinesiology/faculty/conrad-z.php/">Zach Conrad</a>, total spending on food in the United States per person per day, between 2001 and 2016, was $13.27, and $3.62 worth of that expenditure, or 27%, was wasted food. </p>
<p>Conrad found that just 1.4% of that waste involved frozen food, amounting to about 5 cents per person per day, or $18.25 annually. But those nickels add up to more than $5.89 billion worth of frozen food wasted every year. </p>
<p>So as the <a href="https://www.statista.com/topics/1339/frozen-foods-market/">frozen food market</a> continues to grow, the importance of minimizing or preventing ice damage becomes obvious. </p>
<h2>Preventing ice growth with artificial substances</h2>
<p>The synthetic chemicals that prevent ice recrystallization tend to be toxic to living organisms, so their usefulness for protecting food is very limited. Via its lengthy and rigorous review process, <a href="https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=175.300&SearchTerm=polyvinyl%20alcohol">the U.S. Food and Drug Administration has approved</a> an artificial polymer called polyvinyl alcohol, or PVA, as safe for use in food packaging materials, but not as a food additive. </p>
<p>PVA is used industrially to prevent ice recrystallization in substances like <a href="https://doi.org/10.1016/j.xcrp.2020.100060">cement and concrete</a>, as well as <a href="http://doi.org/10.1038/ncomms4244">when freezing human cells, tissues and organs</a> to preserve them for transplantation and biotechnology uses. </p>
<p>There are also “semi-synthetic” compounds – so labeled because they are made by altering naturally occurring materials – that hold promise for curbing ice damage. They include substances called <a href="https://doi.org/10.1021/jacs.8b02066">glycopolymers</a> and <a href="https://doi.org/10.1016/j.biomaterials.2009.05.025">polyampholytes</a>, which have been reported to inhibit ice recrystallization, preserve cells and increase cell viability. Many of these compounds are in early stages of research and development, and not yet used commercially. Their safety for use in food has yet to be demonstrated or approved. </p>
<h2>A safer alternative: Bio-based solutions</h2>
<p>I research alternatives to both synthetic and semi-synthetic materials that are bio-based – that is, based on substances already found in humans, animals and plants, and through natural biological processes. I believe that these bio-based solutions are especially promising options because they don’t involve unnatural manipulation. </p>
<figure class="align-center ">
<img alt="A school of Arctic char underwater in the Oxara river, Thingvellir National Park, Iceland" src="https://images.theconversation.com/files/416077/original/file-20210813-15-flu74x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/416077/original/file-20210813-15-flu74x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/416077/original/file-20210813-15-flu74x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/416077/original/file-20210813-15-flu74x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/416077/original/file-20210813-15-flu74x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/416077/original/file-20210813-15-flu74x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/416077/original/file-20210813-15-flu74x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The freeze-resistant proteins in the tissues of cold-tolerant plants and animals, like the Arctic char, hold promise for finding safe new ways to reduce ice recrystallization damage to frozen foods, agricultural crops and biomedical research materials.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/arctic-char-oxara-river-thingvellir-national-park-royalty-free-image/1187633011">DigitalVision via Getty Images</a></span>
</figcaption>
</figure>
<p>For instance, for the egg processing industry, I discovered how to use natural peptides derived from eggs – short strings of amino acids also found in our guts – to <a href="https://doi.org/10.1016/j.foodchem.2018.04.071">prevent freezing-caused damage to egg yolks</a>, rather than adding salt or sugar to yolk before freezing. </p>
<p>Under our National Science Foundation grant, my team is researching substances that mimic the functions of the <a href="https://www.nature.com/articles/s41598-018-36546-2">antifreeze proteins</a> found in cold-water fish or cold-tolerant plants, which <a href="https://doi.org/10.3390/biom10020274">inhibit ice recrystallization</a> and prevent ice growth in their internal tissues.</p>
<p>One challenge is that these antifreeze protein molecules are present in very low concentrations in nature. This makes them very costly to extract from organisms and produce them at an industrial scale. </p>
<p>We are conducting research on peptides derived from both common and unique food proteins, such as soybeans, dairy, fish, meat and insects. Thanks to research by <a href="https://foodsci.wisc.edu/damodaran.html">Srinivasan Damodaran</a> of the University of Wisconsin, we already know that <a href="https://doi.org/10.1021/jf0724670">small peptides from fish gelatin and cattle collagen proteins</a> are effective in preventing ice recrystallization in ice cream. This power of peptides varies greatly depending on the source protein, however, so we are investigating the reasons for these differences.</p>
<p>As we learn more about these peptides and how to produce them at a commercial scale, I believe they may be useful across several industries, from improving the quality of frozen foods, to increasing the resistance of agricultural crops to freezing temperatures, to better preserving cells and tissues, and even in uses like de-icing roads and aircraft. </p>
<p>[<em>Get our best science, health and technology stories.</em> <a href="https://theconversation.com/us/newsletters/science-editors-picks-71/?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=science-best">Sign up for The Conversation’s science newsletter</a>.]</p><img src="https://counter.theconversation.com/content/164989/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tong (Toni) Wang receives funding from National Institute of Food and Agriculture of United States Department of Agriculture, National Dairy Council, and National Science Foundation. </span></em></p>Scientists are looking for safe new ways to prevent ice from damaging food in frozen storage, which costs consumers billions of dollars a year in wasted food.Tong (Toni) Wang, Professor, food scientist, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1568392021-05-05T15:52:44Z2021-05-05T15:52:44ZHow scientists make plant-based foods taste and look more like meat<figure><img src="https://images.theconversation.com/files/398505/original/file-20210503-17-1094vef.jpeg?ixlib=rb-1.1.0&rect=36%2C42%2C3961%2C2090&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The science behind trying to build the perfect plant-based meat is full of trial and error and a multidisciplinary team. </span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>In 2019, Burger King Sweden released a plant-based burger, the Rebel Whopper, and the reaction was underwhelming. So, the company challenged its customers to taste the difference. </p>
<p><a href="https://www.cnbc.com/2019/07/15/burger-king-5050-menu-doles-out-meat-or-plant-based-burgers-randomly.html">Burger King Sweden created menu item</a> where customers would have a 50-50 chance of getting a meat burger or a plant-based one. To find out, they had to scan the burger box in Burger King’s app. The results: 44 per cent guessed wrong — customers couldn’t tell the difference.</p>
<p>Plant-based meats are products designed to imitate meat. While earlier products like tofu and seitan were meant to replace meat, newer products are trying to mimic its taste, texture, smell and appearance. <a href="https://www.greenmatters.com/p/plant-based-meats">Plant-based burgers, ground meat, sausages, nuggets and seafood</a> are now in grocery stores and on restaurant menus. They aim to redefine our understanding of meat.</p>
<p>Achieving such standards is not an easy task. It took Beyond Meat more than six years to develop the Beyond Burger. And since its release in 2015, it has been through three reformulations. The science behind trying to build the perfect plant-based meat is full of trial and error — and involves a multidisciplinary team. </p>
<h2>The Maillard reaction</h2>
<p>Appearance, texture and flavour are the three main challenges food scientists face when developing a convincing plant-based meat. These are what give meat its characteristics and essence.</p>
<p>When meat cooks, its texture changes. The <a href="https://doi.org/10.1016/j.meatsci.2004.11.021">temperature of the pan or the grill affects protein structures</a>. As proteins begin to break down, coagulate and contract, the meat tenderizes and firms up. </p>
<p>What’s known as the <a href="https://www.seriouseats.com/2017/04/what-is-maillard-reaction-cooking-science.html">Maillard reaction</a> is responsible for that distinctive “meaty” aroma and savoury flavour. Understanding it helps food research and development teams replicate it in plant-based meat products. </p>
<figure class="align-center ">
<img alt="A variety of meats on a barbecue grill" src="https://images.theconversation.com/files/398479/original/file-20210503-17-q26qbl.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/398479/original/file-20210503-17-q26qbl.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=521&fit=crop&dpr=1 600w, https://images.theconversation.com/files/398479/original/file-20210503-17-q26qbl.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=521&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/398479/original/file-20210503-17-q26qbl.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=521&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/398479/original/file-20210503-17-q26qbl.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=654&fit=crop&dpr=1 754w, https://images.theconversation.com/files/398479/original/file-20210503-17-q26qbl.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=654&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/398479/original/file-20210503-17-q26qbl.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=654&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Maillard reaction is responsible for that distinctive ‘meaty’ flavour.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Ingredients also influence appearance, texture and flavour. Soy, wheat, pea and fava proteins, as well as starches, flours, <a href="https://www.edinformatics.com/math_science/hydrocolloids.htm">hydrocolloids</a> (non-digestible carbohydrates used as thickeners, stabilizers and emulsifiers, or as water retention and gel-forming agents) and oils, can make a plant-based meat more or less similar to the animal meat it is trying to replicate. </p>
<p>Finally, the processing method influences the product’s final characteristics. <a href="https://www.ift.org/news-and-publications/food-technology-magazine/issues/2019/october/columns/processing-how-plant-based-meat-and-seafood-are-processed">“High-moisture extrusion” and “shear-cell” technologies</a> are two of the most common processes used to transform vegetable protein into a layered fibrous structure that closely matches the appearance and texture of meat. <a href="https://doi.org/10.1016/B978-0-08-100596-5.03099-7">High-moisture extrusion is the most used</a> technique and provides a meat-like bite, but <a href="https://doi.org/10.1080/10408398.2020.1864618">shear cell processing</a> is more energy-efficient and has a smaller carbon footprint.</p>
<h2>Colour and texture</h2>
<p>Food scientists are now able to simulate meat colour before, during and after cooking. Beet extract, pomegranate powder and <a href="https://www.nytimes.com/2017/08/08/business/impossible-burger-food-meat.html">soy leghemoglobin</a> have been used to mimic the red colour of fresh or rare beef.</p>
<p>Animal protein texture is difficult to copy with plant-based ingredients because plants do not have muscle tissue. Muscles are elastic and flexible, while plant cells are rigid and unbending. Plants do not have the bite and chewiness of meat, which is why veggie burgers can often feel crumbly and mushy. </p>
<figure class="align-center ">
<img alt="Food dishes on a table with the words 'impossible' around them." src="https://images.theconversation.com/files/398476/original/file-20210503-19-yemo4g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/398476/original/file-20210503-19-yemo4g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/398476/original/file-20210503-19-yemo4g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/398476/original/file-20210503-19-yemo4g.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/398476/original/file-20210503-19-yemo4g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/398476/original/file-20210503-19-yemo4g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/398476/original/file-20210503-19-yemo4g.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A variety of Impossible Pork dishes from Impossible Foods, the California plant-based meat company.</span>
<span class="attribution"><span class="source">(AP Photo/Ross D. Franklin)</span></span>
</figcaption>
</figure>
<p>A key ingredient in any plant-based meat is the plant protein. In addition to being <a href="https://doi.org/10.1111/1541-4337.12610">fundamental to the structure</a>, it is also important for product identity and differentiation. A formulation can use one type of protein or a blend of different types. </p>
<p>Soy protein is still the plant protein that delivers the most meat-like taste and texture. Since it has been used for decades now, a lot of research has been done and its texturization process has been further improved. </p>
<p><a href="https://www.businesswire.com/news/home/20201222005307/en/8-Billion-Plant-based-Meats-Markets-2025-by-Source-Soy-Wheat-Pea-Others-Product-Burger-Patties-Strips-Nuggets-Sausages-Meatballs-Other-Type-Beef-Chicken-Pork-Fish---ResearchAndMarkets.com">Pea protein</a>, made popular by Beyond Meat, is the fastest growing segment in the plant-based market because of its complete <a href="https://www.aicr.org/resources/blog/health-talk-pea-protein-is-everywhere-is-it-healthy/">amino acid profile</a>. </p>
<p>There are nine amino acids that are essential in our diets. Animal-based foods have all of them and are considered complete proteins. Most plant foods are incomplete proteins, meaning certain amino acids are missing, but pea protein contains all nine. </p>
<figure class="align-center ">
<img alt="A pair of petri dishes: one containing a piece of uncooked chicken, the other holding chickpeas." src="https://images.theconversation.com/files/398477/original/file-20210503-15-166kv8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/398477/original/file-20210503-15-166kv8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=296&fit=crop&dpr=1 600w, https://images.theconversation.com/files/398477/original/file-20210503-15-166kv8k.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=296&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/398477/original/file-20210503-15-166kv8k.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=296&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/398477/original/file-20210503-15-166kv8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=372&fit=crop&dpr=1 754w, https://images.theconversation.com/files/398477/original/file-20210503-15-166kv8k.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=372&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/398477/original/file-20210503-15-166kv8k.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=372&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Most plant foods are incomplete proteins, but pea protein contains all nine essential amino acids.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Pea protein also lacks allergens. Rice, fava, chickpea, lentil and mung bean proteins have also generated a lot of interest among food scientists, and more products incorporating these plants are expected to come to market in the future.</p>
<h2>Creating flavour</h2>
<p>Companies don’t have to disclose flavouring ingredients — only whether they’re natural or artificial — so it’s hard to know what exactly gives plant-based burgers that meat-like flavour.</p>
<p>Fat is a major player in flavour and mouth feel. It provides mouth-coating richness, juiciness and is responsible for flavour release. It activates certain areas of the brain that are responsible for processing taste, aroma and reward mechanisms. </p>
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Read more:
<a href="https://theconversation.com/diet-resolutions-6-things-to-know-about-eating-less-meat-and-more-plant-based-foods-148871">Diet resolutions: 6 things to know about eating less meat and more plant-based foods</a>
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<p>The industry standard has been to use coconut oil to replace animal fat. However, coconut oil melts at much lower temperature than animal fat. In the mouth this translates to bites that start off rich and juicy, but wear off quickly. Some plant-based meats use a combination of plant-based oils, such as canola and sunflower oils, to increase the melting temperature and extend the juiciness.</p>
<p><a href="https://www.foodnavigator.com/Article/2020/07/10/Cubiq-s-smart-fat-takes-on-coconut-oil-This-is-what-plant-based-companies-are-looking-for">New replacements</a> for <a href="https://www.foodnavigator.com/Article/2021/03/04/Cultivating-animal-fat-for-plant-based-meat-Nobody-wants-a-burger-that-tastes-of-coconut">animal fats</a> using sunflower oil and water emulsions and cultivated animal fats (fat cells grown in laboratories) are <a href="https://www.foodnavigator.com/Article/2020/12/15/Cultivated-fat-a-solution-to-the-plant-based-sensory-gap">being developed</a> to solve this problem. But clearly, not all of these would suit a vegetarian or vegan diet.</p>
<figure class="align-center ">
<img alt="Frozen steaks with the label cultured meat." src="https://images.theconversation.com/files/398478/original/file-20210503-23-1ohuxtn.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/398478/original/file-20210503-23-1ohuxtn.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/398478/original/file-20210503-23-1ohuxtn.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/398478/original/file-20210503-23-1ohuxtn.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/398478/original/file-20210503-23-1ohuxtn.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/398478/original/file-20210503-23-1ohuxtn.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/398478/original/file-20210503-23-1ohuxtn.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Fats provide much of the flavour and feel of meat, and replicating the richness of fat with plant-based replacements can be challenging.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>A plant-based meat formulation can work on paper, have the recommended number of ingredients and hit the nutritional targets to match meat, but it might not taste good or have the right texture or bite. For example, potato protein creates great texture, but it is very bitter. Food scientists must find a balance between the protein content, texture and flavour.</p>
<h2>The future of formulated food</h2>
<p>Food scientists have only scratched the surface when it comes to unlocking the potential of plant-based meats. There is still a lot to explore and improve.</p>
<p>The current commercially available plant protein ingredients come from <a href="https://www.foodingredientsfirst.com/news/shift20-industry-is-only-scratching-the-surface-of-plant-based-proteins.html">two per cent of about 150</a> plant protein species used for food supply.</p>
<p>There is ongoing research exploring crop optimization via breeding or engineering to increase protein content to support further development and improvement of plant protein isolates and ultimately plant-based meats.</p>
<p>Processing method technologies are still being developed and we are seeing new technologies such as <a href="https://www.foodnavigator.com/Article/2021/02/17/Redefine-Meat-prepares-for-European-launch-with-29m-boost-Our-alt-meat-products-will-hit-Switzerland-and-Germany-mid-year">3D printing</a> and <a href="https://sentientmedia.org/lab-grown-meat/">cultured meat</a> being adopted and refined. Expect to see plant-based meat products increase and whole cuts, like <a href="https://www.foodnavigator.com/Article/2020/06/30/Redefine-Meat-launches-3D-printed-steak-This-is-the-start-of-a-new-era-in-alternative-meat">beef steaks</a>, to be commercially available soon.</p><img src="https://counter.theconversation.com/content/156839/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mariana Lamas does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Appearance, texture and flavour are the three main challenges food scientists face when developing a convincing plant-based meat.Mariana Lamas, Research assistant, Centre for Culinary Innovation, Northern Alberta Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1488712020-12-15T18:48:03Z2020-12-15T18:48:03ZDiet resolutions: 6 things to know about eating less meat and more plant-based foods<figure><img src="https://images.theconversation.com/files/374325/original/file-20201210-14-1gyuzvq.jpg?ixlib=rb-1.1.0&rect=99%2C77%2C7249%2C4814&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Plant-based alternative foods have grown in popularity, but it's important to read the labels to know if they're healthy.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Many people are making <a href="https://news.gallup.com/poll/282779/nearly-one-four-cut-back-eating-meat.aspx">changes to their diets to eat healthier or in a more environmentally friendly manner</a>. They might choose to eat less meat, less sugar or even adopt an entirely vegan diet. A growing number, however, are choosing a <a href="https://www.health.harvard.edu/blog/what-is-a-plant-based-diet-and-why-should-you-try-it-2018092614760">plant-based diet</a> that focuses on foods that come from plants, but may still include animal products, such as meat or cheese.</p>
<p>American biochemist Thomas Colin Campbell <a href="https://nutritionstudies.org/history-of-the-term-whole-food-plant-based/">coined the term “plant-based” in the 1980s</a> to better explain his research on diet and nutrition. The term surged in popularity in 2016 when Campbell’s book <a href="https://well.blogs.nytimes.com/2011/01/07/nutrition-advice-from-the-china-study/"><em>The China Study</em></a> was reprinted and alternative meat products such as <a href="https://www.greenqueen.com.hk/one-year-on-how-beyond-meats-ipo-changed-plant-based-meat-forever/">Beyond Burger</a> and <a href="https://channels.theinnovationenterprise.com/articles/how-impossible-foods-are-disrupting-the-meat-industry">Impossible Burger</a> were launched.</p>
<p>Since then, plant-based foods have taken the world by storm. They are everywhere: <a href="https://www.businessinsider.com/burger-king-tgi-fridays-chains-sell-plant-based-meat-2019-5">fast-food chains</a>, restaurant menus, grocery stores, <a href="https://netbasequid.com/blog/plant-based-food-analytics/">social media</a>, food blogs and on your plate. The global plant-based food market is predicted to reach a market valuation of <a href="https://univdatosmarketinsights.medium.com/plant-based-food-market-global-industry-analysis-size-share-growth-trends-and-forecast-2a0c4dd7867">US$38.4 billion by 2025</a>. In the United States alone, the number of plant-based products available increased <a href="https://www.gfi.org/marketresearch">29 per cent between 2017 and 2019</a>.</p>
<p>As a research assistant at the Centre for Culinary Innovation, I work with industry to develop new food products. Although the work of the centre is not limited to plant-based foods, our team focuses on researching, understanding, experimenting and creating new ones.</p>
<p>The rapid growth of plant-based food is due to several factors. The most common reasons people <a href="https://prowly-uploads.s3.eu-west-1.amazonaws.com/uploads/landing_page_image/image/265983/7215af9e9e6ba9b1279d555f919bb57a.pdf">in Europe</a>, <a href="https://www.fooddive.com/news/study-consumers-try-plant-based-meat-because-theyre-curious/571615/">the U.S.</a> and <a href="https://doi.org/10.1080/10454446.2019.1566806">Canada</a> give for eating plant-based food are the health benefits, curiosity to try new food, environmental concerns and animal welfare.</p>
<p>If you are thinking about switching to a plant-based diet, here are six things you should know about plant-based food.</p>
<h2>1. Understand what plant-based means</h2>
<p>According to the <a href="https://d2evkimvhatqav.cloudfront.net/documents/pbfa_nsf_certified_pb_definition_only.pdf">Plant Based Foods Association</a>, a plant-based product consists of ingredients derived from plants, including vegetables, fruits, whole grains, nuts, seeds or legumes. </p>
<p>The final product directly replaces an animal product. By this definition, a cheese made from plant sources can be called plant-based, but flour or bread cannot. If the final product only partially replaces an animal product, then it should be labelled as a blend.</p>
<figure class="align-center ">
<img alt="Packages of plant-based meat products in a freezer." src="https://images.theconversation.com/files/374321/original/file-20201210-15-aaap9v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/374321/original/file-20201210-15-aaap9v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/374321/original/file-20201210-15-aaap9v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/374321/original/file-20201210-15-aaap9v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/374321/original/file-20201210-15-aaap9v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=539&fit=crop&dpr=1 754w, https://images.theconversation.com/files/374321/original/file-20201210-15-aaap9v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=539&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/374321/original/file-20201210-15-aaap9v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=539&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Grocery stores are carrying an increasing number of plant-based protein substitutes.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<h2>2. A plant-based diet may not be vegan or vegetarian</h2>
<p><a href="https://www.health.harvard.edu/blog/what-is-a-plant-based-diet-and-why-should-you-try-it-2018092614760">The terms vegan and plant-based have long been used interchangeably</a>. But following a plant-based diet does not necessarily mean that you are vegan or vegetarian. It means that you are consciously choosing to eat more from plants, but you may still be eating meat, fish, eggs or other animal products.</p>
<p>In fact, plant-based food manufacturers <a href="https://www.businessinsider.in/retail/news/how-meat-eaters-not-vegans-are-driving-the-plant-based-foods-boom-according-to-industry-experts/articleshow/78238518.cms">are not targeting vegans and vegetarians</a> since they are only a small percentage of the population. Their main targets are meat eaters and flexitarians — people who eat mostly plant-based diets, but still eat meat.</p>
<h2>3. Plant-based food is not a synonym for healthy</h2>
<p>Usually, a diet containing a higher proportion of plant-based food is automatically associated with <a href="https://www.fooddive.com/news/plant-based-eating-makes-consumers-feel-healthier-study-says/542175/">being healthy</a>. However, it might not always be the case.</p>
<p>A plant-based diet is healthy when it is mainly composed of whole foods such as vegetables, fruits, legumes and nuts. In fact, such a diet <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3662288/">has been shown to decrease the risk of chronic diseases</a> like heart disease, diabetes and cancer.</p>
<p>Nutritionists remain concerned about <a href="https://www.health.harvard.edu/blog/impossible-and-beyond-how-healthy-are-these-meatless-burgers-2019081517448">heavily processed meat substitutes that contain high levels of saturated fats and sodium</a>. These ingredients — preservatives, flavouring and fillers — enhance the taste, shelf life and texture. </p>
<p>Although they are considered natural, they are not necessary for a healthy diet. They may be environmentally friendly, but they may not be healthy, especially in large amounts.</p>
<h2>4. Plant-based food is changing the way we eat</h2>
<p>Plant-based food is not going away anytime soon. In fact, what we are seeing now is a global increase of plant-based products. </p>
<p>What started with soy milk in the 1990s, and continued with almond milk in the 2000s and burgers in 2010s, has expanded to different types of plant-based products: pork, chicken, yogurt, ice cream, seafood, fish, <a href="https://nationalpost.com/life/food/plant-based-eggs-are-coming-to-canadian-freezer-sections">eggs</a>, cheese, sausage, jerky and more.</p>
<figure class="align-center ">
<img alt="a package of vegan eggs" src="https://images.theconversation.com/files/374323/original/file-20201210-14-un6pxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/374323/original/file-20201210-14-un6pxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/374323/original/file-20201210-14-un6pxj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/374323/original/file-20201210-14-un6pxj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/374323/original/file-20201210-14-un6pxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/374323/original/file-20201210-14-un6pxj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/374323/original/file-20201210-14-un6pxj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Plant-based egg alternatives have been developed to appeal to people who like the look and mouthfeel of scrambled eggs.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>While Gen X and baby boomers may be more resistant to change their diets, <a href="https://www.forbes.com/sites/michaelpellmanrowland/2018/03/23/millennials-move-away-from-meat/">millennials</a> and <a href="https://thebeet.com/gen-zers-want-to-eat-more-vegan-or-plant-based-foods-new-survey-finds/">Gen Z</a> — who are more likely to consider the food source, animal welfare issues and environmental impacts when making their purchasing decisions — are embracing plant-based food and will continue to do so. </p>
<p>Millennials did not invent this type of eating, but they are re-inventing it and spurring a broader change in attitudes and consumption of plant-based food. Gen Z is growing up with plant-based eating as a norm.</p>
<h2>5. Plant-based food is as ‘good’ as its ingredients</h2>
<p>What goes unnoticed by many consumers is how these products are made. Replacing animal food products is not an easy task, quite the opposite, it is a very complex one. </p>
<p>It takes years to research and develop plant-based food products. And it has only been possible because of the ingredients available, such as plant proteins, oils, flavourings and binders. The better they are, the better the final product will be. Not only in the sense of texture, appearance, flavour and mouthfeel, but also health.</p>
<p>The next wave of plant-based products will likely be healthier as better ingredients and processes (like 3D printing) will be available. If we look at Beyond Burger, for example, <a href="https://www.foodnavigator-usa.com/Article/2020/11/16/Beyond-Meat-to-unveil-two-new-burgers-in-early-2021-removes-mung-bean-protein-promises-enhanced-meaty-flavor">the new formulation is healthier than the previous one</a>.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/LJYWM-5taIE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This 3D printer can produce about six kilograms of plant-based steak per hour.</span></figcaption>
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<h2>6. Plant-based is good for the planet, but be careful</h2>
<p>One of the main reasons consumers switch to a plant-based diet is because of sustainability and environmental concerns. Indeed, <a href="https://www.bbc.com/news/science-environment-49238749">eating plant-based reduces the impacts of climate change, saves water and minimizes agricultural land use</a>.</p>
<p>But be aware that many <a href="https://www.nytimes.com/2019/10/14/business/the-new-makers-of-plant-based-meat-big-meat-companies.html">plant-based brands</a> are a part of a larger operation. A specific brand may be sustainable and environment friendly, but the company that owns it may not be.</p>
<p>It is important that food companies be transparent. Consumers have the right to know where the products they buy come from and how they are made so they can make informed decisions and hold companies and brands accountable.</p><img src="https://counter.theconversation.com/content/148871/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mariana Lamas does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Plant-based diets can be healthy but ingredients matter. Heavily processed meat substitutes can be high in saturated fats and sodium.Mariana Lamas, Research assistant, Centre for Culinary Innovation, Northern Alberta Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1390122020-06-17T11:19:18Z2020-06-17T11:19:18ZHealthier food can contain more contaminants – but there’s a simple way to stay safe<figure><img src="https://images.theconversation.com/files/342543/original/file-20200617-94070-1q0vkn4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/food-storage-wooden-shelf-pantry-grain-1681776787">VH Studio/Shutterstock</a></span></figcaption></figure><p>A <a href="https://www.sciencedirect.com/science/article/pii/S0147651320304401">recent study</a> found that brown and organic rice sold in the UK tends to contain significantly more arsenic than white non-organic varieties that are often considered less healthy. Arsenic is found in many foods but can be <a href="https://www.nutrition.org.uk/nutritioninthenews/headlines/arsenicinrice.html?__cf_chl_jschl_tk__=0cfff5cc20203fef57a7f0abe9b1a85152aed58b-1589892797-0-AYmZvmOiiv_74fZJJSryyTnFV43AyehQhet-M_4bgSLRRtAqwafR-5tsQaItVhiyTkpgyDWu4qNaiojRSeuyPNVCq0VsAgXAXN8rlR8qz_OMY5jERQC1Cdjad7JMzUexYlUSTojatdc993jz4re95-qcfjTmRx-sdIdENyvshMVwv-lczOfB2175XG57sesDjGYzcSm7j8g93zoItYbUInGTxPQIpZu_kh_BifQ3fu2ZkfsNRlnyZWGtJ0mn36PLb3SdarTfEQ8YnIrrvsDPPbLDRCPO4nZ827AsYOJczhc0HYFSKfCZig15Qzu-h_5fy66oVjfqfUycswAdV1a56EywEzGBQqyj4fnIzQDR1DehECYlOBxWNT_kLYmunTEU0bduR-UtNTpreqBbVuGQ3-0">especially concentrated in rice</a>, particularly in the outer layers, which are removed to produce white rice but retained in brown rice.</p>
<p>Consuming too much arsenic over a long period is thought to be dangerous because it can cause cancer. Yet brown rice is usually considered healthier than white because of the extra fibre and vitamins it contains. Organic rice is less likely to have been exposed to pesticides. </p>
<p>Ascertaining exactly what a healthy diet consists of can be full of these apparent paradoxes. Should you eat brown rice for the fibre or white rice for the lower arsenic levels? The answer shows the potential difficulties of using studies like the one cited above to guide dietary choices and the need to fully understand the complexities of nutrition and dietary choices. </p>
<h2>Arsenic in rice</h2>
<p>For adults, the reality is that even eating one kilogram of cooked brown rice a day is <a href="https://pubmed.ncbi.nlm.nih.gov/18448219/">unlikely to cause</a> the consumption of too much arsenic. Also because brown rice <a href="https://www.bda.uk.com/resourceDetail/printPdf/?resource=wholegrains">is a wholegrain</a>, eating it will also supply you with more fibre (a nutrient very few UK adults reach the recommended 30g per day of), as well as wide range of vitamins, minerals and essential fatty acids.</p>
<p>Children under five are more at risk of consuming too much arsenic from rice but a varied diet and <a href="https://www.food.gov.uk/safety-hygiene/arsenic-in-rice">avoiding rice drinks</a> should mitigate this. You can also reduce arsenic in rice by up to 80% by rinsing it and cooking it in copious amounts of water.</p>
<h2>Mercury in fish</h2>
<p>Some varieties of fish can also contain significant amounts of mercury, specifically methylmercury, which can be toxic to humans, causing kidney damage and affecting foetal and infant brain development. Levels of methylmercury can be particularly high in fish that eat other fish, such as shark, swordfish, marlin and tuna.</p>
<p>The <a href="https://efsa.onlinelibrary.wiley.com/doi/pdf/10.2903/j.efsa.2015.3982">European Food Safety Authority</a> says up to 1.3 micrograms of methylmercury per kg of bodyweight per week is a safe amount. For a typical 90kg adult that equals 117mcg a week. The amount of methylmercury in a single portion of fish in this category can vary hugely but EU rules mean 1kg should contain no more than 500mcg.</p>
<p>For the most commonly eaten type of fish in this category, tinned tuna, a 100g drained tin could contain as much as 50mcg of methyl mercury. So eating more than two tins a week could theoretically put you at greater risk. Shark, swordish and marlin tend to contain more mercury so more caution is advised here, and you should avoid them <a href="https://www.nhs.uk/common-health-questions/pregnancy/should-pregnant-and-breastfeeding-women-avoid-some-types-of-fish">if you are pregnant</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/342544/original/file-20200617-94049-1glqe6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/342544/original/file-20200617-94049-1glqe6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/342544/original/file-20200617-94049-1glqe6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/342544/original/file-20200617-94049-1glqe6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/342544/original/file-20200617-94049-1glqe6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/342544/original/file-20200617-94049-1glqe6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/342544/original/file-20200617-94049-1glqe6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">You’d have to eat a lot of tuna to be harmed by its mercury content.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/food-storage-wooden-shelf-pantry-grain-1681776787">HandmadePictures/Shutterstock</a></span>
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<p>But most tins of tuna aren’t likely to contain the maximum allowed amount of mercury and reports of bodybuilders and other tuna enthusiasts becoming ill with mercury poisoning are rare.</p>
<p>Meanwhile, fish <a href="https://www.bhf.org.uk/informationsupport/heart-matters-magazine/nutrition/oily-fish?gclid=Cj0KCQjwzZj2BRDVARIsABs3l9IH1K15bUbc8ol3nAJF0QIr0AeKkPiM7SqZ5oVLeQy__nKsO0DmU5caAqpBEALw_wcB&gclsrc=aw.ds">contributes to a healthy</a> Mediterranean-style diet linked to lower chances of type 2 diabetes, high blood pressure and raised cholesterol. Oily fish (such as sardines, mackerel, salmon, trout or herring) are particularly beneficial in this respect and contain nutrients important for foetal and early infancy brain development. So most adults who eat fish <a href="https://www.nhs.uk/live-well/eat-well/fish-and-shellfish-nutrition/">are advised to aim</a> for at least two portions a week including at least one type of oily fish.</p>
<h2>Pesticides in vegetable skins</h2>
<p>It’s well established that the peels and skins of fruit and vegetables are an important source of fibre, helping to <a href="https://journals.rcni.com/nursing-standard/evidence-and-practice/understanding-the-role-of-carbohydrates-in-optimal-nutrition-ns.2019.e11323/print/abs">maintain digestive health</a> and control blood glucose levels. These outer layers also <a href="https://www.bda.uk.com/uploads/assets/622d08b0-c391-4b50-a7e9eeac006f354a/Fruit-Veg-food-fact-sheet.pdf">tend to contain</a> more vitamin C, minerals and other beneficial “phenolic” compounds than the flesh. </p>
<p>But there is <a href="https://www.pan-uk.org/our-food">also some concern</a> that pesticides used to treat seeds, growing plants or harvested crops can collect in particularly high concentrations in skins, although the actual amounts vary hugely. <a href="https://www.theverge.com/2017/10/26/16553942/apples-wash-pesticides-baking-soda-chemicals-organic-peel-fruit">Some people argue</a> you should peel your fruits and vegetables as a result.</p>
<p>But the actual amounts of pesticide residue that can be found in fruit and veg is limited. The UK government’s <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/879216/prif-monitoring-2019-quarter3.pdf">most recent research</a> on the issue only found samples that exceeded the maximum legal pesticide residue level in a small number of samples in four out of 14 types of fruit and vegetables tested.</p>
<p>The <a href="https://www.who.int/news-room/fact-sheets/detail/pesticide-residues-in-food">World Health Organization</a> says: “None of the pesticides that are authorised for use on food in international trade today are genotoxic” (damaging to DNA, which can cause mutations or cancer). </p>
<p>Someone with a healthy or high bodyweight and/or a varied diet is very unlikely to be exposed to enough pesticide to breach this level. In contrast, the evidence for the benefits of eating fruits and vegetables including the skins is overwhelming. So it still seems prudent that we eat as much as we can and, where possible and palatable, consume the skins. </p>
<p>These examples underline why the “everything in moderation” we often see in <a href="https://www.nhs.uk/live-well/eat-well/the-eatwell-guide/">healthy eating guidelines</a> really does seem to be the best approach. The more types of food we eat, the less of each we consume and therefore we can reduce the chance of doing ourselves harm from either too much or too little of something. But knowing what the safe limits are can help answer some of the more difficult questions about what’s the best food choice.</p><img src="https://counter.theconversation.com/content/139012/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ruth Fairchild does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A new study shows high-fibre brown rice also contains more arsenic than white rice – so which is better for you?Ruth Fairchild, Senior Lecturer in Nutrition, Cardiff Metropolitan UniversityLicensed as Creative Commons – attribution, no derivatives.