Study on the dynamic changes of nutrient components and flavor compounds during the fermentation process of high-quality highland barley wine

The purpose of this study was to comprehensively understand the formation mechanism of nutrient components and flavor compounds during the fermentation process of high-quality highland barley wine (HHBW). The dynamic changes of physicochemical properties, non-volatile compounds and volatile flavor compounds in HHBW at different fermentation times were investigated. The results indicated that the nutrient components and physiologically active substances in HHBW, such as proteins, β-glucan, total phenols and total flavonoids were higher than those in commercial highland barley wine (HBW). In addition, the analysis results of HS-SPME-GC-MS revealed significant differences in flavor compounds at each fermentation stage, with alcohol being the main flavor compound. The contents of aldehydes and ketones decreased rapidly with the progress of fermentation. Lactic acid was the most important organic acid in HHBW. Correlation analysis revealed a negative association between citric acid and most alcohols and esters, while tartaric acid and succinic acid exhibited positive correlations with alcohols. Bitter amino acids, such as valine, isoleucine, leucine, arginine and lysine, were positively correlated with most of the ester flavor compounds. The study can provide a reference for a deep understanding of the mechanism of the formation of the characteristic flavor of HHBW.