Comparative characterization and contribution of key aroma compounds in the typical base liquor of Jiang-flavor Baijiu from different distributions in the Chinese Chishui River basin

Abstract

The characteristic of typical base liquor is crucial in controlling ultimate quality of <i>Jiang</i>-flavor <i>Baijiu</i>. This study investigates the flavor compounds of three typical base liquors (<i>Jiangxiang</i>, <i>Chuntian</i>, and <i>Jiaodixiang</i>) by LLE/LLME/HS-SPME, gas chromatography-mass spectrometry (GC-MS), gas chromatography-flame ionization detection (GC-FID), sensory analysis, and odor activity value (OAV). Of the 201 main volatile compounds identified, 37 significant compounds distinguished the three typical base liquors. Acid (441.72 ± 0.17 mg/L), alcohol (5388.88 ± 0.55 mg/L), and ester compounds (8181.64 ± 0.15 mg/L) were respectively marked in <i>Jiangxiang</i>, <i>Chuntian</i>, and <i>Jiaodixiang</i> typical base liquors. Orthogonal partial least squares discriminant analysis (OPLS-DA), correlation analysis, and aroma recombination showed that butyric acid (OAV: 102.23), butyl 2-methylbutyrate (OAV: 6045.59), and ethyl caproate (OAV: 418.37) were significantly correlated with sweet, fruity, pit mud, <i>jiang</i>, and ethanol aromas. It identifies the primary constituents that affect flavor variations in the three typical base liquors and provides guidance for investigations on the flavor formation of <i>Jiang</i>-flavor <i>Baijiu</i>.