Modelling the formation of heterocyclic amines in slices of longissimus thoracis and semimembranosus beef muscles subjected to jets of hot air

The formation of heterocyclic amines (HAs) was modelled in slices of longissimus thoracis (LT) and semimembranosus (SM) beef muscles subjected to jets of hot air at temperatures ranging from 170 and 250 °C and treatment times ranging from 1 to 20 min. The quantity of HAs formed in the SM muscle was clearly less that that formed in the LT muscle as soon as the heat treatment was longer than 300 s. The extreme dehydration obtained with the hot-air jets slowed the formation of IQx, MeIQx and, particularly, 4,8-DiMeIQx compared with superheated steam treatments. The reverse effect was observed for PhIP concentrations which increased 1.4- to 5.5-fold. This highlights the important effect of water activity variations on HA formation, even at very low aw values.