Health Aspects of Barbecue Foods
by Dr. Deryck D. Pattron, Ph.D.
Summary: Barbecue foods are often favored by consumers worldwide, because of its unique organoleptic properties. But, are barbecue foods safe for human consumption? Research has shown that frequent consumption of barbecue foods may increase the risk of developing stomach cancer, colorectal, pancreatic and breast cancer in females. The causative factor may be linked to the formation of heterocyclic amines (
HCA) in barbecue foods. HCA are formed by the action of high temperatures on amino acids and creatinine in muscle tissue in meat, poultry and fish (MPF). Routes of formation and methods of preventing, reducing or eliminating the formation of HCA in foods are discussed. Key words: barbecue foods, public health, HCA, MPF. Introduction-The Problem: We are now in the barbecue or summer season when outdoor activities may lead to or influence the consumption of barbecue meats and foods. But, is it really safe to consume large amounts of barbeque meats over a short time period or is it safe to consume small amounts of barbecue foods over a prolonged period on a regular basis? These questions have been on the minds of researchers, scientists and food safety thinkers, worldwide.
Research has shown that heterocyclic amines (HCA) are commonly formed in meat, poultry and fish foods containing creatine and creatinine when cooked at temperatures above 325 °F. It has been further shown that HCA are linked to stomach cancer, colorectal cancer, pancreatic and breast cancer in females.
The purpose of the present study is to review and evaluate existence evidence and to present a concise exposition to the general public on the safety of barbecue foods and to present useful recommendations on ways to reduce, eliminate or prevent the formation of HCA in meat, poultry and fish containing foods.
What are heterocyclic amines? Heterocyclic amines are organic cyclic molecules containing hydrogen atoms, methyl groups and amino groups in addition to carbon atoms in its molecular structure. At least 17 chemically different heterocyclic amines have been identified so far, but 24 have been reported to date in the current literature. The five most commonly found heterocyclic amines in the Western diet include: i. PhIP. ii. MeIQx. iii. DiMeIQx. iv. IQ. v. A?C.
How is heterocyclic amines formed in barbecue foods? Heterocyclic amines are formed via two routes: ? The first route involves the reaction of amino acids with each other at high temperatures. ? The second route involves the reaction of amino acids and/or some sugars with creatine or creatinine at high temperatures.
It must be noted however, that not all foods containing amino acids when heated form appreciable amounts of heterocyclic amines. What then determines whether a food will form appreciable amounts of heterocyclic amines?
What factors influence the formation of heterocyclic amines in foods? ? Temperature. This is one of the most significant factors. Foods such as meat, poultry and fish when heated at temperatures above 325 ºF can form significant amounts of heterocyclic amines. ? Time. Meat, poultry and fish heated at high temperatures for 4 to 10 minutes can form significant amounts of heterocyclic amines. ? Contact with heat source. Foods that are cooked in direct contact with heat source such as barbecuing, pan frying, broiling, flame grilling can lead to significant amounts of heterocyclic amines. ? Food composition. Muscle foods from meat, poultry and fish contain high levels of creatine, creatinine and amino acids that can react at high temperatures to form significant levels of heterocyclic amines.
Recommendations to reduce, prevent or eliminate the formation of heterocyclic amines in foods: ? Use different methods of cooking meats. For example use methods other than frying, broiling and barbecuing. ? Trim visible fat off meats prior to barbecuing. ? Avoid making gravy from meat drippings. ? Use small cuts of meat when barbecuing. ? Avoid cooking meats over 325 ºF for prolonged periods. ? Precook meat before barbecuing reduces heterocyclic amines by up to 95 %. ? Turn-over meat or foods frequently to avoid reaching high temperatures. This may reduces the internal temperature by up to 100 %. ? Marinate meat before barbecuing reduces heterocyclic amines by up to 92-95 %. ? Use a meat thermometer and cook meat to the proper internal temperature. Do not over cook meat. Chicken should be cooked at an internal temperature of 165 ºF. Hamburger, pork, hot dogs should be cooked at 160 ºF, 150 ºF and 140 ºF, respectively. ? Cut and remove charred portions off the meat. ? Eat a variety of foods. ? Eat vegetables (such as cabbage, broccoli, cauliflower, kale and brussel sprouts) one or two days before eating barbecue. It is believed that these vegetables contain compounds that activate enzymes in the body that detoxify heterocyclic amines. ? Consume fruits and fruit juices such as cherries, orange juice, lime juice, cranberries juice or blueberries containing high levels of vitamin C. This can inhibit the formation of heterocyclic amines. ? Consume foods containing vitamin E as this can inhibit the formation of heterocyclic amines.
Conclusion: ? Barbecuing a common method of cooking is linked to stomach cancer, colorectal, pancreatic and breast cancer. ? The causative agent identified is heterocyclic amines. ? Heterocyclic amines are commonly formed in meat, poultry and fish when cooked at temperatures exceeding 325 °F. ? Heterocyclic amines formation can be reduced or eliminated by: * Using alternative cooking methods. * Pre-cooking meats prior to barbecuing. * Pre-treatment of meats such as marinating prior to barbecuing. * Frequent turning of foods during barbecuing. * Cook foods at proper temperatures. * Avoid using meat drippings to make gravies. * Do not eat charred meat. * Trim fat off meats prior to barbecuing. * Eating a variety of foods including fruits and vegetables.
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About the Author
Dr. Pattron is a Public Health Scientist and Consultant.