Heterocyclic amine formation during frying of frozen beefburgers

The formation of heterocyclic amines (HCAs) was studied during frying of beefburgers with different fat contents (6.7%, 16.1% and 39%). Beefburgers were fried from the frozen state for 60, 90, 120 s, and until the centre temperature had reached 72 °C (approximately 150 s) in a double-sided pan fryer. The beefburgers were analysed for HCAs with solid-phase extraction and LC/MS detection, and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 1-methyl-9H-pyrido[3,4-b]indole (Harman) and 9H-pyrido[3,4-b]indole (Norharman) were detected in all samples. The concentrations of HCAs ranged between 0 and 2.3 ng g−1. The HCAs concentrations were fitted to a first-order reaction model. The amounts of HCAs in beefburgers fried from the frozen state were in the same range as in beefburgers that have reached room temperature before frying. Furthermore, it was found that the formation of HCAs is not only concentration-controlled but also mass transport-controlled and that kinetic models stated in earlier studies fit relatively well our analysed values on HCAs in fried beefburgers.