tag:theconversation.com,2011:/ca/topics/bbq-4302/articlesBBQ – The Conversation2022-06-03T12:17:15Ztag:theconversation.com,2011:article/1842062022-06-03T12:17:15Z2022-06-03T12:17:15ZWhat makes smoky, charred barbecue taste so good? The chemistry of cooking over an open flame<figure><img src="https://images.theconversation.com/files/466829/original/file-20220602-15-5dw0hs.jpg?ixlib=rb-1.1.0&rect=156%2C260%2C1637%2C1085&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cooking food over an open flame produces unique flavors thanks to some interesting chemistry. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/man-preparing-food-on-barbecue-grill-royalty-free-image/717232191?adppopup=true">Lars Szatmari / EyeEm via Getty Images</a></span></figcaption></figure><p>The mere thought of barbecue’s smoky scents and intoxicating flavors is enough to get most mouths watering. Summer is here, and that means it is barbecue season for many people in the U.S.</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 – including barbecue. Cooking on a grill may seem simple, but there is a lot of chemistry that sets barbecue apart from other cooking methods and results in such a delicious experience.</p>
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<a href="https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Burning charcoal with a reddish glow at the center." src="https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=423&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=423&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=423&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=532&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=532&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466834/original/file-20220602-20-nek9jj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=532&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">Cooking over an open flame – whether from gas, wood or charcoal – allows you to use both radiant and conductive heat to cook food.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Charbon_de_bois_rouge.jpg#/media/File:Charbon_de_bois_rouge.jpg">Romary/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<h2>Cooking with fire</h2>
<p>First, it is important to define barbecue because the term can mean different things in different cultures or geographic locations. At its most basic, barbecue is the cooking of food over an open flame. What sets barbecue apart from other cooking methods is how heat reaches the food.</p>
<p>On a barbecue, the hot grill grates heat the food via direct contact through a process known as <a href="https://www.physicsclassroom.com/class/thermalP/Lesson-1/Methods-of-Heat-Transfer">conduction</a>. The food also warms and cooks by absorbing <a href="https://www.physicsclassroom.com/class/thermalP/Lesson-1/Methods-of-Heat-Transfer">radiation</a> directly from the flames below. The mix of heating methods allows you to sear the parts of the food touching the grill while simultaneously cooking the parts that aren’t touching the griddle – like the sides and top – through radiating heat. The resulting range of temperatures creates a complex mixture of flavors and aromas. When cooking on a stovetop, there is much less radiation and most of the cooking is done where the food is in direct contact with the pan.</p>
<p>When barbecuing, you can either put the food directly above the flames – what is called <a href="https://barbecuebible.com/recipe/direct-vs-indirect-grilling/">direct heat</a> – or farther away on indirect heat. The direct cooking method subjects the food to very high temperatures, as the grilling surface can be <a href="https://barbecuebible.com/recipe/direct-vs-indirect-grilling/">anywhere from 500 to 700 degrees Fahrenheit</a> (260 to 371 Celsius). The indirect cooking method places the heat source to the side of the food or far below, exposing the food to temperatures around 200 to 300 F (93 to 149 C). </p>
<p>Cooking is the process of using <a href="https://www.scienceofcooking.com/enzymatic-non-enzymatic-browning-of-foods.html">high temperatures to drive chemical reactions</a> that change food at a molecular level. When you cook meat at higher temperatures – like over direct heat on a barbecue – the first thing to happen is that water near the meat’s surface boils off. Once the surface is dry, the heat causes the proteins and sugars on the outside of the meat to undergo a reaction called the <a href="https://cen.acs.org/articles/90/i40/Maillard-Reaction-Turns-100.html">Maillard Reaction</a>. This reaction produces a complex mixture of molecules that make food taste more savory or “meaty” and adds depth to scents and flavors. The reaction and the flavors it produces are influenced by many variables, including temperature and acidity as well as the ingredients within any sauces, rubs or marinades.</p>
<p>A similar process occurs with vegetables. Barbecuing allows the water to evaporate or drip down without getting trapped by a pan. This keeps the vegetables from becoming soggy and promotes <a href="https://doi.org/10.1016/0308-8146(94)90188-0">caramelization reactions</a>. These reactions turn carbohydrates and sugars into smaller compounds like <a href="https://doi.org/10.1021/jf60171a044">maltol</a> – which has a toasty flavor – and furan – which tastes nutty, meaty and caramel-like.</p>
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<a href="https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A piece of corn and a large mushroom showing blackened spots." src="https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466833/original/file-20220602-14-1352n5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&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">It’s much easier to control the level of charring on food when cooking on a barbecue.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Barbecue_corn_and_mushroom_(7872340508).jpg#/media/File:Barbecue_corn_and_mushroom_(7872340508).jpg">Lablascovegmenu/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<h2>Char and crisp</h2>
<p>Another hallmark of barbecued food is the unique char it develops. When foods are exposed to heat for prolonged periods of time, non-carbon atoms in the food break down, leaving behind the crispy, black carbon. This is the process of <a href="https://www.masterclass.com/articles/charred-food-explained#quiz-0">burning or charring</a>. </p>
<p>Almost no one likes a completely burnt piece of meat, but little splashes of crispy char flavor can add such depth to foods. Cooking over the direct heat of a barbecue allows you to add just the amount of char to match your taste.</p>
<p>Unfortunately for those who like a little extra crisp, some of the chemicals in charred meat – molecules called heterocyclic amines and polycyclic aromatic hydrocarbons – are known <a href="https://doi.org/10.1080%2F01635580802710741">carcinogens</a>. Though the dangers are far lower than smoking cigarettes, for example, limiting the amount of charring on meats <a href="https://blog.dana-farber.org/insight/2019/09/does-burnt-food-cause-cancer/">can help reduce the risk of developing cancer</a>. </p>
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<span class="caption">Smoke gives barbecued foods much of their unique flavor.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Harry_Knight_2017-05-28_(Unsplash).jpg#/media/File:Harry_Knight_2017-05-28_(Unsplash).jpg">Harry Knight/Unsplash Photos</a></span>
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<h2>Smoky flavors</h2>
<p>The final quintessential barbecue flavor is smokiness. Cooking over wood or charcoal involves a lot of smoke. Even on a gas grill, melting fats will drip onto the heat source and produce smoke. As smoke swirls around the barbecue, the food will absorb its flavors.</p>
<p>Smoke is made up of gases, water vapor and small solid particles from the fuel. Burning wood breaks down molecules called <a href="https://www.smokedbbqsource.com/science-of-smoke/">lignans</a>, and these turn into <a href="https://doi.org/10.1002%2Ffsn3.9">smaller organic molecules</a> – including syringol and guaiacol – that are mainly responsible for the quintessential smoky flavor.</p>
<p>When smoke comes in contact with food, the components of the smoke can <a href="https://www.smokedbbqsource.com/science-of-smoke/">get absorbed</a>. Food is particularly good at taking on smoky flavors because it contains both fats and water. Each binds to different types of molecules. In chemistry terms, fats are non-polar – meaning they have a weak electric charge – and easily grab other non-polar molecules. Water is polar – meaning it has areas of positive charge and an area of negative charge similar to a magnet – and is good at binding to other polar molecules. Some foods are better at absorbing smoky flavors than others, depending on their composition. One way to use chemistry to make food more smoky is to periodically spray it with water during the barbecuing process.</p>
<p>Smoke can contain hundreds of possible <a href="https://www.epa.gov/burnwise/wood-smoke-and-your-health">carcinogens</a> depending on what you are burning. Only a <a href="https://www.cancer.gov/about-cancer/causes-prevention/risk/diet/cooked-meats-fact-sheet">small amount of research</a> has been done on whether grilled foods absorb enough smoke to pose a significant risk to health. But researchers know that <a href="https://www.lung.org/clean-air/at-home/indoor-air-pollutants/residential-wood-burning">inhaling smoke</a> is strongly correlated with cancer.</p>
<p>While the idea of barbecuing your favorite dish may evoke the feeling of simple pleasures, the science behind it is quite complex. The next time you enjoy the smoky goodness of food from a grill, you will hopefully appreciate the diverse nature of the compounds and reactions that helped produce it.</p><img src="https://counter.theconversation.com/content/184206/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>Barbecued food has unique and often delicious flavors. A food chemist explains how the process of grilling over an open flame can produce flavors unattainable through other cooking methods.Kristine Nolin, Associate Professor of Chemistry, University of RichmondLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1007162018-08-15T12:46:02Z2018-08-15T12:46:02ZThe big BBQ debate: how best to fuel your outdoor feast<figure><img src="https://images.theconversation.com/files/232075/original/file-20180815-2891-11oih4r.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/bbq-cleaning-griil-on-fire-before-1154160085?src=14sOm5Ak95Olb4_sU_h8sg-2-1">Shutterstock</a></span></figcaption></figure><p>The smoky aroma of a barbecue is a familiar smell on warm sunny evenings around the world. In countries like Australia, the “barbie” is such an intrinsic part of the culture that open public spaces are often equipped with permanent barbecues to enable and encourage communal cooking. In cooler climates like the UK, people make do with having their own private barbecue in the garden – or a portable or disposal version for the beach or park. </p>
<p>But is a barbecue a healthy way to cook? And which type of barbecue – gas or coal – is best to cook on for taste and flavour?</p>
<p>With respect to health, there are two things to think about: first, ensuring the food is <a href="https://www.food.gov.uk/safety-hygiene/barbecues">safely cooked through</a>, and second, avoiding the production of unhealthy chemicals during the cooking process. </p>
<p>Ensuring a high and even temperature for the right amount of time is essential to cook the food properly, and kill any bacteria it might contain which could make us unwell. Doing this is easier with a gas or electric barbecue, where the temperature can be easily controlled. </p>
<p>When cooking over charcoal, it can be more difficult to get the temperature right. If it is too high, the food can be charred but dangerously uncooked in the centre. Or if the charcoal is not burning evenly, there may be cold spots on the grill, leading to uneven cooking. </p>
<p>A charcoal barbecue with a temperature gauge, or which allows you to vary the amount of air getting to the coals can help. To make extra sure, think about using a <a href="https://www.foodsafety.gov/blog/thermometer.html">food probe thermometer</a> to check that high risk foods such as meat (especially reformed products such as kebabs and burgers) are cooked through to the middle.</p>
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<span class="caption">Cooking on gas.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/step-by-grilling-new-york-strip-1128412442?src=KZ-pOJcYTFh939TK1Dtpyg-5-54">Shutterstock</a></span>
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<h2>Boot leather BBQs</h2>
<p>So, hopefully at this stage, you and your guests can expect food that is at least safe to eat. The next step is to cook it so the texture is right. This will depend on what you are trying to cook. If it is a meat with lots of connective fibres in it, like brisket or stewing steak, the barbecue is probably not the best place to be cooking it. This type of meat needs to be <a href="https://www.bbcgoodfood.com/howto/guide/brisket">cooked slowly</a> to help break down the tough white collagen and convert it into melt-in-the-mouth meat. </p>
<p>Thin steaks without these fibres, like sirloin, are best cooked quickly, at high temperatures, whether you like them rare, medium or well done. But again it comes down to control, which is easier with a gas or electric barbecue. The more even the temperature, the easier it is to cook the meat just how you like it.</p>
<p>With respect to flavour, some favour the smoke you get from charcoal. But that is only probably important if things are cooked slowly. Otherwise, the key factor is likely to be heat. This area is a balancing act, not just because the chemicals produced from the charcoal sizzle have been associated with an <a href="https://www.cancer.gov/about-cancer/causes-prevention/risk/diet/cooked-meats-fact-sheet">increased risk of cancer</a>, but also because too many spits and flames can leave too much of a sooty coating on the food you have been carefully marinading and cooking. </p>
<p>That said, sizzling can certainly add smoky flavours, and perhaps this is the one area where real coals are the best option. But considering the variability in temperature, and the risk of over- or under-cooking, on balance, you are probably better off playing safe with gas or electric for reliable heat and safely-cooked foods. </p>
<h2>Smoke Signals</h2>
<p>But cooking on electric or gas doesn’t have to be dull. It is still possible to introduce smokey flavours with marinades which can also help improve the texture of meat. Fruits such as pineapple and kiwi can tenderise meat, as can the acid in vinegars. Other tasty flavours can be obtained from adding garlic, chilli and other spices. </p>
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<p>It is even possible that some marinades can <a href="https://academic.oup.com/ajcn/article/92/4/996/4597632">reduce the production</a> of harmful chemicals during cooking.</p>
<p>With gas barbecues, there are also ways to add smokey flavours by using specific wood chips – such as applewood, mapple, hickory or mesquite. The key here is not to overdo it, as smoking the food too much will make it taste bitter and unpleasant. But with the increasing popularity of smoked foods, many gas barbecues now come with a special smoking box. These also can be bought separately, or even improvised from aluminium takeaway containers. Just make sure the lid is metal, too, as paper or cardboard will just go up in smoke… </p>
<p>Overall, the key factors which will affect the success (and healthiness) of your barbecue are the amount of heat you generate, the amount of control you have over the heat, and the amount of smoke. But in cooler countries like the UK, the biggest factor is often the weather – as the simple act of lighting a barbecue, whether it’s gas or electric or charcoal, often leads to just one disappointing result: the appearance of a rain cloud.</p><img src="https://counter.theconversation.com/content/100716/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Duane Mellor is a director, council member and spokesperson of the British Dietetic Association.</span></em></p>A nutritionist’s expert view on barbecue success.Duane Mellor, Senior Lecturer, Coventry UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/511252015-12-27T21:38:46Z2015-12-27T21:38:46ZYou ‘can’ thaw and refreeze meat: five food safety myths busted<figure><img src="https://images.theconversation.com/files/105989/original/image-20151215-23186-1izrmc9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">So it turns out you can thaw out meat and refreeze it. Who knew? </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/osseous/16818464851/">Osseous/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>This time of year, most fridges are stocked up with food and drinks to share with family and friends. Let’s not make ourselves and our guests sick by getting things wrong when preparing and serving food. </p>
<p>As the weather warms up, so does the environment for micro-organisms in foods, potentially allowing them to multiply faster to hazardous levels. So put the drinks on ice and keep the fridge for the food.</p>
<p>But what are some of those food safety myths we’ve long come to believe that aren’t actually true?</p>
<h2>Myth 1: if you’ve defrosted frozen meat or chicken you can’t refreeze it</h2>
<p>From a safety point of view, it is fine to refreeze defrosted meat or chicken or any frozen food as long as it was defrosted in a fridge running at 5°C or below. Some quality may be lost by defrosting then refreezing foods as the cells break down a little and the food can become slightly watery. </p>
<p>Another option is to cook the defrosted food and then divide into small portions and refreeze once it has stopped steaming. Steam in a closed container leads to condensation, which can result in pools of water forming. This, combined with the nutrients in the food, creates the perfect environment for microbial growth. So it’s always best to wait about 30 minutes before refrigerating or freezing hot food.</p>
<p>Plan ahead so food can be defrosted in the fridge, especially with large items such as a frozen turkey or roll of meat. If left on the bench, the external surface could be at room temperature and micro-organisms could be growing rapidly while the centre of the piece is still frozen!</p>
<h2>Myth 2: Wash meat before you prepare and/or cook it</h2>
<p>It is not a good idea to wash meats and poultry when preparing for cooking. Splashing water that might contain potentially hazardous bacteria around the kitchen can create more of a hazard if those bacteria are splashed onto ready-to-eat foods or food preparation surfaces.</p>
<p>It is, however, a good idea to wash fruits and vegetables before preparing and serving, especially if they’re grown near or in the ground as they may carry some dirt and therefore micro-organisms. </p>
<p>This applies particularly to foods that will be prepared and eaten without further cooking. Consuming foods raw that traditionally have been eaten cooked or otherwise processed to kill pathogenic micro-organisms (potentially deadly to humans) might increase the risk of food poisoning.</p>
<p>Fruit, salad, vegetables and other ready-to-eat foods should be prepared separately, away from raw meat, chicken, seafood and other foods that need cooking.</p>
<h2>Myth 3: Hot food should be left out to cool completely before putting it in the fridge</h2>
<p>It’s not OK to leave perishable food out for an extended time or overnight before putting it in the fridge. </p>
<p>Micro-organisms can grow rapidly in food at temperatures between 5° and 60°C. Temperature control is the simplest and most effective way of controlling the growth of bacteria. Perishable food should spend as little time as possible in the 5-60°C danger zone. If food is left in the danger zone, be aware it is potentially unsafe to eat.</p>
<p>Hot leftovers, and any other leftovers for that matter, should go into the fridge once they have stopped steaming to reduce condensation, within about 30 minutes.</p>
<p>Large portions of hot food will cool faster if broken down into smaller amounts in shallow containers. It is possible that hot food such as stews or soup left in a bulky container, say a two-litre mixing bowl (versus a shallow tray), in the fridge can take nearly 24 hours to cool to the safe zone of less than 5°C.</p>
<h2>Myth 4: If it smells OK, then it’s OK to eat</h2>
<p>This is definitely not always true. Spoilage bacteria, yeasts and moulds are the usual culprits for making food smell off or go slimy and these may not make you sick, although it is always advisable not to consume spoiled food. </p>
<p>Pathogenic bacteria can grow in food and not cause any obvious changes to the food, so the best option is to inhibit pathogen growth by refrigerating foods.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=451&fit=crop&dpr=1 600w, https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=451&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=451&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=567&fit=crop&dpr=1 754w, https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=567&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/105994/original/image-20151215-23198-zm6ev4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=567&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Just because something passes the sniff test, doesn’t make it OK.</span>
<span class="attribution"><span class="source">www.shutterstock.com</span></span>
</figcaption>
</figure>
<h2>Myth 5: Oil preserves food so it can be left at room temperature</h2>
<p>Adding oil to foods will not necessarily kill bugs lurking in your food. The opposite is true for many products in oil if anaerobic micro-organisms, such as <em>Clostridium botulinum</em> (botulism), are present in the food. A lack of oxygen provides perfect conditions for their growth.</p>
<p>Outbreaks of botulism arising from consumption of vegetables in oil – including garlic, olives, mushrooms, beans and hot peppers – have mostly been attributed to the products not being properly prepared.</p>
<p>Vegetables in oil can be made safely. In 1991, Australian regulations stipulated that this class of product (vegetables in oil) can be safely made if the pH (a measure of acid) is less than 4.6. Foods with a pH below 4.6 do not in general support the growth of food-poisoning bacteria including botulism.</p>
<p>So keep food out of the danger zone to reduce your guests’ risk of getting food poisoning this summer. Check out other food safety tips and resources from <a href="http://www.csiro.au/en/Research/Health/Food-safety">CSIRO</a> and the <a href="http://www.foodsafety.asn.au/resources">Food Safety Information Council</a>, including <a href="http://foodsafetyinfo.polldaddy.com/s/food-safety-myths">testing your food safety knowledge</a>.</p><img src="https://counter.theconversation.com/content/51125/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cathy Moir is a Senior Food Microbiologist and Team Leader with the CSIRO Food and Nutrition and is Vice President of the Food Safety Information Council, a not for profit organisation.</span></em></p>What are some of those food safety myths we’ve long come to believe that aren’t actually true?Cathy Moir, Team leader, Microbial and chemical sciences, Food microbiologist and food safety specialist, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/204212013-12-19T02:09:07Z2013-12-19T02:09:07ZSlip a more sustainable prawn on your barbie this Christmas<figure><img src="https://images.theconversation.com/files/36760/original/pzckdqsw-1386043297.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Prawns sold in Australian supermarkets must be labelled with the country of origin. About half of the prawns we buy are from overseas.</span> <span class="attribution"><span class="source">Flickr: avlxyz</span></span></figcaption></figure><p>Australians are set to munch through half a billion prawns this Christmas. But where do all those prawns come from? And can we feel good as we throw another one on the barbie?</p>
<p>About half of the prawns eaten in Australia come from overseas. More than A$200 million worth of frozen prawns were imported in 2011–2012, mainly from southeast and east Asia, and these imports are on the rise.</p>
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<figcaption>
<span class="caption">Whiteleg shrimp.</span>
<span class="attribution"><span class="source">Wikimedia Commons/Xufanc</span></span>
</figcaption>
</figure>
<p>Most of the imported prawns are farm-grown and the main species is commonly known as vannamei, or white shrimp.</p>
<p>The rapid growth of prawn farming has generated public debate over its sustainability and effects on the environment.</p>
<p>Concerns have surrounded the destruction of mangrove areas, coastal pollution, salinisation, wild prawn collection, the use of marine-based feeds, and conflict with other resource users.</p>
<p>But there is some good news: according to the <a href="http://www.fao.org/fishery/culturedspecies/Litopenaeus_vannamei/en">Food and Agriculture Organization</a> of the United Nations, worldwide environmental certification programs such as <a href="http://www.globalgap.org/uk_en/">Global Gap</a> are having a positive influence on farming practices.</p>
<p>Growers are breeding prawns that use protein more efficiently, and adopting low-water-exchange pond systems with less environmental impact. These <a href="http://ag.arizona.edu/azaqua/ista/ISTA9/PDF's/Yoram-BFT%20Brief%20Summary%205.3.11.pdf">aerated systems</a> encourage the growth of bacteria and other microorganisms that recycle unused food. Other advances include better biosecurity and traceability, and reduced chemical residues.</p>
<p>Australian scientists are supporting better aquaculture practices in Vietnam by helping farmers to establish prawn breeding programs that improve farm productivity.</p>
<h2>Australian farmed prawns</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/37821/original/p988v3md-1387156121.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/37821/original/p988v3md-1387156121.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/37821/original/p988v3md-1387156121.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/37821/original/p988v3md-1387156121.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/37821/original/p988v3md-1387156121.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/37821/original/p988v3md-1387156121.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/37821/original/p988v3md-1387156121.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/37821/original/p988v3md-1387156121.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">Australian wild-caught white banana prawns.</span>
<span class="attribution"><span class="source">Paul Harris, CSIRO</span></span>
</figcaption>
</figure>
<p>About 20% of Australian prawns are farm grown. Australia has some 20 prawn farms, located mainly in Queensland. The most common farmed species is the black tiger prawn, followed by the banana prawn.</p>
<p>Australian prawn farmers have worked with scientists to develop healthy, <a href="http://www.csiro.au/en/Outcomes/Food-and-Agriculture/tiger-prawn-farming.aspx">fast-growing</a> prawns that can be produced efficiently on farms that meet the world’s highest standards for environmental management.</p>
<p>Research has also addressed the industry’s perceived dependency on marine-based feeds.</p>
<h2>What do prawns eat?</h2>
<p>Farmed prawns are fed on a compounded pellet made from a range of ingredients that satisfies their nutritional needs.</p>
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<figcaption>
<span class="caption">CSIRO marine scientists Rik Buckworth and Tonya van der Velde inspect prawns from the Northern Prawn Fishery at the Raptis Fish Markets in Brisbane.</span>
<span class="attribution"><span class="source">Paul Harris, CSIRO</span></span>
</figcaption>
</figure>
<p>In Australia, the ingredients include soybeans, lupins and canola, and recycled waste proteins, plus small amounts of sustainably-sourced fish meal and fish oil. But now the technology exists to phase-out these marine ingredients.</p>
<p>A new food <a href="http://www.csiro.au/Portals/Media/Perfect-food-for-perfect-prawns.aspx">additive</a> developed by CSIRO has been shown to improve prawn growth rates by 30% and eliminates the need for fish products in their diet. The additive is moving towards commercial production in Australia and Asia.</p>
<h2>Trawling for prawns</h2>
<p>The rest of our prawns are harvested by 500 prawn trawlers that operate across 15 Australian fisheries off Queensland, the Northern Territory, Western Australia, South Australia and New South Wales.</p>
<p>The main species caught are <a href="http://fish.gov.au/reports/crustaceans/prawns/Pages/Eastern-king-prawn.aspx">king prawns</a>, <a href="http://fish.gov.au/reports/crustaceans/prawns/Pages/white_banana_prawn.aspx">banana prawns</a>, <a href="http://fish.gov.au/reports/crustaceans/prawns/Pages/tiger_prawns.aspx">tiger prawns</a>, school prawns and <a href="http://fish.gov.au/reports/crustaceans/prawns/Pages/blue_and_red_endeavour_prawns.aspx">endeavour prawns</a>. </p>
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<figcaption>
<span class="caption">A brown tiger prawn.</span>
<span class="attribution"><span class="source">www.fish.gov.au</span></span>
</figcaption>
</figure>
<p>Wild-caught Australian prawns are available year-round, although some seasonality occurs. Many of the fisheries are remote, so catches are commonly packaged and frozen on board the vessels.</p>
<p>Australian prawn fisheries, like all Australian fisheries, are recognised as among the best-managed in the world.</p>
<p>Scientists work with managers and industry to set fishing levels that are strictly regulated and monitored. Escape hatches in the trawl nets have been used for more than a decade to reduce the capture of large species, and all prawn fisheries must pass ecological assessments to meet conservation and export regulations.</p>
<p>South Australia’s Spencer Gulf Fishery and the Commonwealth <a href="http://www.csiro.au/Outcomes/Oceans/Marine-Life/Sustaining-fisheries-index/Northern-Prawn-Fishery.aspx">Northern Prawn Fishery</a> have both achieved certification from the Marine Stewardship Council, an independent body that certifies sustainable fisheries worldwide.</p>
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<figcaption>
<span class="caption">A prawn trawler returning to Cairns from the Northern Prawn Fishery.</span>
<span class="attribution"><span class="source"> Brian Cassey, CSIRO</span></span>
</figcaption>
</figure>
<h2>Look out for labels</h2>
<p>All prawns sold at major supermarkets in Australia must be labelled according to the country of origin. </p>
<p>In some states, such as the Northern Territory and South Australia, that compulsory labelling extends to all seafood retail outlets, including restaurants.</p>
<p>Australian prawn farmers and fishers are trying to encourage people to eat Aussie prawns throughout the year with a <a href="http://australianprawns.com.au/">Love Australian prawns</a> campaign in an effort to smooth out some of the logistics associated with stocking so many prawns at Christmas. </p>
<p>So if you do want to buy homegrown prawns, look out for the labels at your supermarket, or ask your fishmonger where they’ll be getting their supplies from this Christmas. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Xn_CPrCS8gs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Paul Hogan’s famous ‘I’ll slip an extra shrimp on the barbie’ ad from 1984.</span></figcaption>
</figure><img src="https://counter.theconversation.com/content/20421/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rik Buckworth receives funding from the Fisheries Research and Development Corporation and the Australian Fisheries Management Authority, which both include some indirect industry funding, as well as funding through the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Greg Coman receives funding through the CSIRO from agriculture industry partnerships. These include the Australian Prawn Farming Association and other prawn farming companies in Australia and overseas.</span></em></p>Australians are set to munch through half a billion prawns this Christmas. But where do all those prawns come from? And can we feel good as we throw another one on the barbie? About half of the prawns…Rik Buckworth, Principal Research Scientist, CSIROGreg Coman, Aquaculture scientist, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/106852012-11-21T19:36:00Z2012-11-21T19:36:00ZHere’s a meaty question – are barbecues bad for your health?<figure><img src="https://images.theconversation.com/files/17778/original/nczwydc6-1353297635.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">There's evidence of both the mechanism and effect for the link between colorectal cancer and high intakes of red meat.</span> <span class="attribution"><span class="source">Gary A. K./Flickr</span></span></figcaption></figure><p>As we settle into the barbecue season, it’s time to consider whether the meat on your grill is harming your health. Conflicting messages in the media certainly don’t help. On one hand are advertisements with Sam Neill claiming red meat is the reason that humans are smarter than orangutans. </p>
<p>On the other, the prestigious World Cancer Research Fund reports that red meat may cause colorectal cancer. Whom to believe?</p>
<h2>The good bits, and bad</h2>
<p>Some red meat does contain fats our brains need. Omega-3 fats form part of the structure of brains and eyes, and may also help reduce blood pressure and modify inflammation. But meat isn’t the only food containing omega-3 fats. In fact, the richest sources are oily fish. </p>
<p>And if you buy grain-fed steak, you may be getting hardly any omega-3 fats at all. Grass-fed meat (and wild meats, such as kangaroo) is not only better for the environment, but better nutritionally, containing healthier fats and a lower fat content overall.</p>
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<p>Red meat also contains decent amounts of zinc and protein, as well as iron, which is one of its big nutritional selling points. Indeed, the iron in red meat is in a form that our bodies absorb easily – “haem” iron. </p>
<p>Meat producers are fond of producing colourful ads that equate the iron content of a bucket-load of spinach with that of a small juicy-looking nugget of lean beef. And iron deficiency is an important issue – but that same haem iron may be harmful in fatty processed meat as you will see.</p>
<p>As well as beneficial nutrients, meat also contains saturated fat, the kind that promotes increased cholesterol levels in the blood and blocks blood vessels that the heart relies on to keep working. </p>
<p>The fat content of meat varies markedly with species and cut. If you buy untrimmed brisket, chuck or shoulder, or luxury marbled meat, such as wagyu or kobe beef, your meat will be around 10% to 20% fat. Ribs, neck, pork belly, and the cheapest minced meat can be up to 50% fat. You can get down to 3% to 5% fat if you trim your meat well of all visible fat and choose leaner cuts, such as loin and round steak, flank and shanks.</p>
<h2>Meat and cancer</h2>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/17774/original/wk8zrzcc-1353295475.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/17774/original/wk8zrzcc-1353295475.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/17774/original/wk8zrzcc-1353295475.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/17774/original/wk8zrzcc-1353295475.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/17774/original/wk8zrzcc-1353295475.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/17774/original/wk8zrzcc-1353295475.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/17774/original/wk8zrzcc-1353295475.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">
<figcaption>
<span class="caption">The haem iron in meat is easier to extract than the iron in spinach.</span>
<span class="attribution"><span class="source">john varghese</span></span>
</figcaption>
</figure>
<p>The cancer risk associated with high consumption of red meat, particularly processed red meat, is definitely cause for concern. In 2007, the World Cancer Research Fund (WCRF) produced an <a href="http://www.dietandcancerreport.org/expert_report/report_contents/index.php">expert report</a> that assessed the evidence for causal links between food, lifestyle and cancer, based on data from all studies that met quality standards. </p>
<p>In the report, the WCRF concluded that there was “convincing” evidence (that is, evidence of both the mechanism and the effect) for a link between colorectal cancer and high intakes of red meat. The link was strongest for processed red meat – bacon, salami, sausages and hot dogs, which contain curing agents such as nitrates and nitrites. </p>
<p>The studies’ data indicated that cancer risk continued to rise with higher meat intakes. This rise appears to start once red meat consumption exceeds 300 grams in a week. The WCRF’s recommendation is that people who eat red meat should consume less than 500 grams a week, including very little if any processed meat products. There was no data to indicate that any level of processed meat intake was free of risk. </p>
<p>Eating fish may help reduce colorectal cancer risk, and some studies indicate that a high fibre intake, and eating lots of fruits and vegetables, are associated with reduced cancer risk.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/17777/original/hrw2hkbj-1353296508.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/17777/original/hrw2hkbj-1353296508.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/17777/original/hrw2hkbj-1353296508.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/17777/original/hrw2hkbj-1353296508.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/17777/original/hrw2hkbj-1353296508.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/17777/original/hrw2hkbj-1353296508.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/17777/original/hrw2hkbj-1353296508.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">
<figcaption>
<span class="caption">Eating fish may help reduce colorectal cancer risk.</span>
<span class="attribution"><span class="source">Eugene Kim</span></span>
</figcaption>
</figure>
<h2>How it works</h2>
<p>How red meat causes the increase in cancer risk is still a question in search of a complete answer. Many different components of meat have been suggested as a mechanism, including the curing agents nitrate and nitrite that are present in processed meat; the fat or the haem iron in meat; the excess protein load that big meat eaters might often consume; and the carcinogens, such as heterocyclic amines (HCAs)and polycyclic aromatic hydrocarbons (PAHs), that can be formed during the cooking of meat. </p>
<p>Protein doesn’t appear to be the culprit, despite the fact that the end products of excess protein intake are quite toxic (these are excreted if the kidneys are working normally). Unlike high-protein diets, high-fat diets have been shown in animal studies to increase cancer risk, apparently promoting gut cancers through their damaging effects in the gut as well as contributing to obesity, which itself is a cancer risk factor. </p>
<p>But studies of low-fat diets haven’t shown a reduction in risk, so other factors may also be involved. The problem with processed meat seems mainly to stem from its salt content (associated with risk of stomach cancer) and its content of nitrates and nitrites, which are added as part of the curing process and can be converted to carcinogens. </p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/17775/original/zgwvyf65-1353295932.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/17775/original/zgwvyf65-1353295932.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=468&fit=crop&dpr=1 600w, https://images.theconversation.com/files/17775/original/zgwvyf65-1353295932.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=468&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/17775/original/zgwvyf65-1353295932.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=468&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/17775/original/zgwvyf65-1353295932.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=588&fit=crop&dpr=1 754w, https://images.theconversation.com/files/17775/original/zgwvyf65-1353295932.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=588&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/17775/original/zgwvyf65-1353295932.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=588&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Carcinogenic substances HCAs and PAHs are produced when you cook your meat at a high temperature or on an open flame.</span>
<span class="attribution"><span class="source">jo/Flickr</span></span>
</figcaption>
</figure>
<p>And unlike the iron in plant foods, the haem iron in meat seems to help produce mutagens and carcinogens in the meat and in the gut by reacting with the fat in the meat, and by helping to convert nitrates and nitrites to their carcinogenic form.</p>
<p>There are a lot of studies showing that the carcinogenic substances HCAs and PAHs are produced when you cook your meat at a high temperature or on an open flame, and that colorectal cancer risk increases when you consume a lot of these. Some people have a genetic sensitivity to HCAs and they’re at even higher risk. </p>
<p>Mysteriously, although barbecuing chicken and seafood produces large amounts of HCAs, these don’t seem to be associated with increased cancer risk, perhaps because they are different types from the ones that red meats produce. And perhaps their lower iron content has something to do with it.</p>
<p>Cooking for shorter times, or at lower temperatures, produces smaller amounts of HCAs and PAHs. Raw meat, surprisingly, is no less digestible than meat cooked briefly either at high or low temperatures. What really makes a <a href="http://pubs.acs.org/doi/pdf/10.1021/jf072999g">difference in digestibility</a> is overcooking until meat is tough. This reduces digestibility significantly but that increases again in long, slow cooking.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/17772/original/jjv6976f-1353295186.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/17772/original/jjv6976f-1353295186.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/17772/original/jjv6976f-1353295186.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/17772/original/jjv6976f-1353295186.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/17772/original/jjv6976f-1353295186.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/17772/original/jjv6976f-1353295186.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/17772/original/jjv6976f-1353295186.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">
<figcaption>
<span class="caption">Marinating meat with certain ingredients may be a good idea for health as much as for flavour.</span>
<span class="attribution"><span class="source">exceptinsects/Flickr</span></span>
</figcaption>
</figure>
<h2>The magic of marinades</h2>
<p>Interestingly, marinating meat may be a good idea for health as much as for flavour. A Portuguese study found that several hours’ <a href="http://pubs.acs.org/doi/pdf/10.1021/jf801837s">marinating in beer</a> or <a href="http://pubs.acs.org/doi/pdf/10.1021/jf0616311">red wine</a> significantly reduced the production of HCAs in beef, perhaps by reducing movement of precursor substances to the surface of the meat, or by adding antioxidants that inhibit the reaction. </p>
<p>Other studies have successfully used <a href="http://link.springer.com/article/10.1007%2Fs002170050364?LI=true">garlic, rosemary, thyme and sage</a>, and <a href="http://www.ncbi.nlm.nih.gov/pubmed/17988088">olive oil with garlic and lemon</a>. Cooking with <a href="http://www.ncbi.nlm.nih.gov/pubmed/12963012">extra-virgin olive oil</a> had a similar effect. But adding sugar or fruit to marinades appears to increase the risk of burning and forming more carcinogens.</p>
<p>So, as you wheel out your barbecue this summer, consider serving sustainable seafood or organic chicken some of the time instead of red meat; stick to smaller serves of grass-fed lean meat, marinated without sugar or salt and cooked to a juicy medium-rare, away from a bare flame; and have plenty of salad with your meal. Food for thought?</p><img src="https://counter.theconversation.com/content/10685/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Suzie Ferrie 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>As we settle into the barbecue season, it’s time to consider whether the meat on your grill is harming your health. Conflicting messages in the media certainly don’t help. On one hand are advertisements…Suzie Ferrie, Clinical Affiliate, University of SydneyLicensed as Creative Commons – attribution, no derivatives.