Abstract:

Three model systems consisting of glucose, creatinine and amino acid (alamine, threonine or glycine)
were used to study the formation of roast flavor and five heterocyclic aromatic amines (HCAs), namely, 2-amino-3-
methylimidazo-[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo-
[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx) and 2-amino-3,7,8-
trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx). The volatile compounds and HCAs were determined by solid phase
micro extraction-gas chromatography-mass spectrometry (SPME-GC-MS) and high performance liquid chromatography
(HPLC), respectively. Results showed that after heating at 130 ℃ for 3 h, the volatile compounds were dominated by
alkyl pyrazines, which are typical components of roast flavor. MeIQ, 4,8-DiMeIQx and 7,8-DiMeIQx were detected in
models Ⅰ and Ⅲ, while only MeIQ and 4,8-DiMeIQx were detected in model Ⅱ. An upward trend in the overall amount
of HCAs was observed for all model systems with increasing heating time though only a small amount of HCAs were detected
within 1.5 h. The total amounts of HCAs in three models were (375.50 ± 15.80), (414.00 ± 18.40), and (363.50 ± 12.20) ng/mL,
respectively after heating for 3 h. The present study will hopefully provide a reference for meat processing, especially for
roast meat, by optimizing the desired flavor while reducing the hazardous chemicals of HCAs as much as possible.

Key words: Maillard model system, moderate temperature, roast flavor, heterocyclic aromatic amines (HCAs)