Abstract: In order to determine the changes of aroma-active compounds (AACs) in high-salt liquid-state fermented soy sauce before and after sterilization, we extracted volatile constituents from the samples by direct solvent extraction combined with solvent-assisted flavor evaporation and analyzed them by gas chromatography-olfactometry (GC-O). Twenty-four AACs were detected, and their structures were identified by comparing their odor characteristics, mass spectral data, and retention indices with those of authentic compounds. Their concentrations were determined with 2-octanol as an internal standard. Based on their concentrations and thresholds, the odor activity values (OAVs) of the AACs were calculated. By analyzing the OAVs obtained, the changes in the aroma of soy sauce before and after sterilization were mainly attributed to 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. This result agreed well with the aroma evaluation.

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