关键词: 白姑鱼, 小黄鱼, 挥发性风味, 气相色谱-嗅辨仪, 香气萃取稀释分析, 校准频率法

Abstract: Monolithic material sorptive extraction (MMSE) combined with gas chromatography-mass spectrometryolfatometry (GC-MS-O) was used to identify the key odor-active compounds of white croaker and small yellow croaker. A total of 42 and 49 volatiles were identified in white croaker and small yellow croaker, respectively. Out of these volatiles, 12 and 6 were selected respectively from the two fish by aroma extraction dilution analysis (AEDA), among which 9 volatiles were identified by comparison of their mass spectra and linear retention indices with published data. For each fish, the top 10 major odor-active compounds were screened out by the modified frequency (MF) method. The compounds with the highest FD value of 40 in white croaker were identified as trimethylamine, 2-octen-1-ol, nonanal, and an unknown compound that smelled like metal. According to MF ranking, trimethylamine and 2-octen-1-ol had greater contributions to the odor of white croaker. The odorants with the highest FD value of 40 in small yellow croaker were hexanal and 2-octen-1-ol, but trimethylamine and unknown compounds that smelled like barbecue had greater contributions to its odor according to MF ranking. 6-Methyl-5-heptane-2-one was another odorous compound that was present in each fish and responsible for their metallic or bloody odor. According to MF ranking, this compound had a greater effect on the odor of white croaker than on small yellow croaker. 2,3-Pentanedione and 1-penten-3-ol, ranked higher among the top 10 odor-active compounds in small yellow croaker, together with trimethylamin, unknown barbecue-like odorants and dimethyl disulfide which was not identified in white croaker may be one of the reasons for the difference in odor between the two fish.

Key words: white croaker, small yellow croaker, volatile compounds, gas chromatography-olfactometry (GC-O), aroma extraction dilution analysis (AEDA), modified frequency (MF)