Formation of heterocyclic amines in slices of longissimus thoracis beef muscle subjected to jets of superheated steam

The kinetics of the formation of heterocyclic amines (HA) were measured on slices of Longissimus thoracis (LT) muscle subjected to impinging jets of superheated steam. Product temperature was either 170 or 200 degrees C and treatment duration ranged from 1 to 20 min. The concentrations of lQx, MelQx, 4,8-DiMelQx and PhIP followed regular kinetic patterns. HA formation increased significantly between 170 and 200 degrees C. The quantities of lQx and 4,8-DiMelQx formed in LT slices were 3 to 4-fold smaller than those formed in meat juices, while quantities of MelQx and PhIP remained comparable. A first-order kinetic model taken from the literature was adapted to describe the results taking into account product temperature variations over the course of the experiment.