Abstract: In order to find the changes of odor-active compounds (OACs) in high-salt liquid-state fermentation soy sauces before and after sterilization, the volatile constituents in the samples were extracted by direct solvent extraction combined with solvent-assisted flavor evaporation, and the isolates were analyzed by gas chromatography-olfactometry (GC-O). Twenty-four OACs were detected, and their structures were identified by comparing the odor characteristics, MS data, and retention indices with those of authentic compounds. Their concentrations were determined by combing 2-octanol as an internal standard with calibration curves of corresponding authentic compounds. Based on their concentrations and thresholds, the odor activity values (OAVs) of OACs were calculated. By analyzing OAVs obtained, the main reasons that the odors of soy sauces before and after sterilization were different were the changes in the concentrations of 3-methylthiopropanal, maltol, 4-hydroxy-5-ethyl-2-methyl-3(2H)-furanone, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, hexanal, vanillin, guaiacol and 4-ethylguaiacol. The result correlates well with that of odor evaluation.

Key words: high-salt liquid-state fermentation soy sauce, odor-active constituents, gas chromatography- olfactometry, sterilization