Effect of microwave pretreatment on heterocyclic aromatic amine mutagens/carcinogens in fried beef patties.

To investigate a method to reduce the amount of mutagenic/carcinogenic heterocyclic aromatic amines formed during frying of ground beef, the mutagenic activity in Salmonella strain TA98 was assessed and the amount of known heterocyclic amines was determined by solid-phase extraction and HPLC. The beef patties received microwave treatment for various times before frying. Microwave pretreatment for 0, 1, 1.5, 2 or 3 min before frying at either 200 degrees C or 250 degrees C for 6 min per side reduced heterocyclic aromatic amine precursors (creatine, creatinine, amino acids, glucose), water, and fat up to 30%, in the patties and resulted in a decrease in mutagenic activity up to 95%. The sum of the four heterocyclic aromatic amines shown to be present--2-amino-3,8-dimethylimidazo[4,5-f]-quinoxaline (MeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4,8-trimethylimidazo-[4,5-f]quinoxaline (DiMeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)--decreased three- to nine-fold compared with control, non-microwaved beef patties fried under identical conditions.