Characterization of the typical fragrant compounds in traditional Chinese-type soy sauce

In this work, a total of 35 important aroma compounds with odor activity values (OAVs) greater than 1 were detected by gas chromatography-mass spectrometry (GC-MS) in traditional Chinese-type soy sauce. Of these, fragrant compounds with aromatic rings (20 compounds) accounted for a large proportion, over 57%. Combining principal component analysis and GC-olfactometry-MS (GC-O-MS), 5-methyl-2-furanmethanethiol (OAV: 284-467), 3-methylbutanal (OAV: 409-938), phenylacetaldehyde (OAV: 47.4-566), 2-phenylethanol (OAV: 7.41-14.3), phenylethyl acetate (OAV: 7.00-18.1) and ethyl phenylacetate (OAV: 12.7-21.3) were confirmed as the typical fragrant compounds among all samples. Furthermore, full two-dimensional gas mass spectrometry (GC x GC-TQMS) was applied and 414 aroma compounds were identified, which included another 85 fragrant compounds with aromatic rings.