Abstract:In order to investigate the differences in flavor quality between Daiginjo and Junmai sake, basic physical and chemical indicators, sensory evaluation and gas chromatography-mass spectrometry (GC-MS) were used to analyze the sensory qualities and aroma compounds. The key flavor compounds and aroma differences were determined by odor activity value (OAV) and variable importance in projection (VIP). The results indicated significant differences in the physical and chemical indicators, sensory quality and key flavor substances between Daiginjo and Junmai sake. Daiginjo sake had a rather high level of alcohol and nitrogen amino acid but relatively low content of total sugar and total acid. It also performed a mellow taste, full-bodied ginjo-ka, and sweet aroma, while Junmai sake displayed a monotonous taste, cereal and herbaceous aroma. The two varieties of sake contained 62 volatile flavor components. Daiginjo showed the highest percentage of esters, while Junmai had the highest proportion of alcohol, both of which exceeded 50%. The orthogonal partial least squares-discriminant analysis (OPLS-DA) revealed a significant cluster separation between the two varieties of sake. According to OAV and VIP analysis, various aroma compounds were detected, including caproic acid, ethyl hexanoate, isoamyl acetate, phenethyl acetate, ethyl butyrate, isoamyl alcohol, ethyl caprylate, ethyl heptanoate, and 1-heptanol. The particular key aroma compounds of Daiginjo sake were ethyl caprylate, ethyl heptanoate and phenylethyl acetate. The identification of different aroma compounds in this study can theoretically support further investigation for the characteristics variations between Daiginjo and Junmai sake as well as domestic sake production and processing.
