We recently showed that marinating meat before grilling can have a great impact on heterocyclic amine levels in chicken. This is part of a unique opportunity to link an environmental exposure to an effect, and to test current risk assessment theories on the effects of human exposures of trace amounts of chemicals. If dietary intervention is shown to be necessary, we have learned that minor modifications in food preparation would be effective in greatly reducing the dietary exposure to heterocyclic amines.
We compared the amounts of two heterocyclic amines, MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine), in marinated and unmarinated control chicken breast meat flame-grilled on a propane barbecue grill. Using an analytical chemistry analysis method of solid-phase extraction and high performance liquid chromatography, we recently determined the levels of several heterocyclic amines formed during cooking. Compared with unmarinated controls, a decrease greater than 87% in heterocyclic amines (PhIP and MeIQx combined) was observed in whole chicken breast marinated for 4 h using a published marinade recipe then grilled for 20, 30, or 40 minutes (see graph).
| The marinade recipe does not seem to be important, commercial marinades and individual ingredients showed the same heterocyclic amine-reducing effects. The recipe we used for our original studies: 1/2 cup packed brown sugar 3 garlic cloves 1 1/2 tsp salt 3 Tbsp mustard 1/4 cup cider vinegar 3 Tbsp lemon juice 6 Tbsp olive oil |
Interestingly, meat color is not necessarily related to the formation of heterocyclic amines. Grilled chicken breast meat can have hundreds of parts-per-billion of heterocyclic amines and be white in color, marinated chicken is much darker due to the browning of sugars in the marinade, yet has much lower heterocyclic amine content. Clearly, cooking conditions can be modified to greatly reduce or eliminate these carcinogens from our diet. The effect of marinating on beef is not so clear since beef does not make such high levels of PhIP without marinating.
Complete details were published in May, 1997: Salmon, C. P., Knize, M. G., and Felton, J. S. Marinating before grilling greatly effects heterocyclic amine carcinogen production in chicken. Food and Chemical Toxicology, vol. 35, pages 433-441.
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Last modified September 23, 1997.