Determination of heterocyclic amines in braised sauce beef.

A simplified and improved analysis method to determine the content of heterocyclic amines (HAs) was developed. Samples were extracted with ethyl acetate, and macrosubstances were removed by centrifugation. The eluent used consisted of methanol/ammonia water (9:1, v/v), and the eluates were directly mixed for further HPLC analysis. A binary mobile phase consisting of 0.05 M ammonium acetate-acetic acid and acetonitrile was used for the separation of 12 HAs, and the excitation and emission wavelengths of 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) were adjusted to the same 315 and 410 nm, respectively. This method was further applied to determine the content of HAs in "Jiang Niu Rou", namely braised sauce beef. Nine kinds of HAs were found in the samples and the total amounts of HAs ranged from 4.33 to 27.15 ng/g. The sterilized samples contained more HAs than un-sterilized samples.