Abstract: The effect of cooking time on the flavor characteristics of sea catfish broth were investigated in this paper. Electronic nose, electronic tongue and gas chromatography-mass spectrometry (GC-MS) were used to analyze the flavor composition of fish broth, and the main flavor compounds were determined by relative odor activity values (ROAV). The results showed that the contents of crude protein, crude fat and ash in fish broth increased significantly (P < 0.05) while moisture content decreased but not significantly (P > 0.05) with the prolongation of cooking time. Soluble peptide content increased significantly (P < 0.05) from 1 h onward. Both electronic nose and electronic tongue could well distinguish the smell and taste of fish broth with different cooking times. Meanwhile, a total of 44 volatile compounds were identified by GC-MS, including aldehydes, alcohols, hydrocarbons, ketones, furans and esters, and 24, 33, 21 and 18 volatiles were detected in fish broth cooked for 0.5, 1, 1.5 and 2 h, respectively. With the extension of cooking time, the relative amounts of aldehydes and alcohols significantly increased. Hexanal, heptanal, (E)-2-heptenal, (E)-2-octenal, nonanal, 1-octene-3-ol, D-limonene and 2-pentylfuran were the main flavor substances in sea catfish broth.

Key words: sea catfish, fish broth, cooking, flavor characteristics