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

Traditional Huangjiu 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-mass spectroscopy (GC-MS) and high-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 Saccharomyces, Aspergillu, and Rhizomucor were dominant, whereas Staphylococcus, Pediococcus and Weissella were the dominant bacterial genera in the late stage. In addition, 11 genera such as Lactobacillus, Saccharopolyspora and Aspergillus (|r| > 0.6, p < 0.05) may contributed to traditional Huangjiu ecosystem stability. Moreover, correlation analysis indicated the dominant microorganisms (Saccharopolyspora, Staphylococcus, Lactobacillus, Saccharomyces and Aspergillus) were positively correlated with key compounds. These results provided theoretical guidance for further study on the flavor regulation of traditional Huangjiu via microbial community level and microbial augmentation.