Dynamic analysis of volatile metabolites and microbial community and their correlations during the fermentation process of traditional Huangjiu (Chinese rice wine) produced around Winter Solstice

Abstract

Traditional <i>Huangjiu</i> produced around Winter Solstice has higher quality and a more harmonious aroma. To investigate the variations of volatile metabolites and microbial communities during fermentation, gas chromatography-ion migration chromatography (GC-IMS), gas chromatography<i>-</i>mass spectroscopy (GC-MS) and high<i>-</i>throughput sequencing were employed. Aroma compounds results showed that alcohols and phenols increased before 45 days of fermentation and then decreased after 45 days, while esters gradually increased. Fungal genera <i>Saccharomyces</i>, <i>Aspergillu</i>, and <i>Rhizomucor</i> were dominant, whereas <i>Staphylococcus</i>, <i>Pediococcus</i> and <i>Weissella</i> were the dominant bacterial genera in the late stage. In addition, 11 genera such as <i>Lactobacillus</i>, <i>Saccharopolyspora</i> and <i>Aspergillus</i> (|r| > 0.6, <i>p</i> < 0.05) may contributed to traditional <i>Huangjiu</i> ecosystem stability. Moreover, correlation analysis indicated the dominant microorganisms (<i>Saccharopolyspora</i>, <i>Staphylococcus</i>, <i>Lactobacillus</i>, <i>Saccharomyces</i> and <i>Aspergillus</i>) were positively correlated with key compounds. These results provided theoretical guidance for further study on the flavor regulation of traditional <i>Huangjiu</i> via microbial community level and microbial augmentation.