Flavor development of traditional Huangjiu (Chinese rice wine) from Jiaxing by consecutive fermentation: Metagenomic and metabolomic evaluation

This study provides an in-depth analysis of the fermentation characteristics of Huangjiu from the Jiaxing region. In terms of physicochemical properties, the total sugar content peaked during the early stage of fermentation, followed by a fluctuating trend of increase and decline, while ethanol content, amino acid nitrogen, and total acidity continuously increased. A total of 64 volatile flavor compounds were identified, including esters, aldehydes, and alcohols. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) revealed significant changes in the volatile profile throughout fermentation, with intergroup differences gradually narrowing. Eight key volatile compounds were identified. Additionally, 39 non-volatile metabolites were detected, primarily amino acids and organic acids, from which nine key non-volatile compounds were screened. Microbial community analysis indicated that fungi dominated the fermentation process, with Saccharomyces cerevisiae exhibiting the highest relative abundance. Thirteen dominant genera and nineteen dominant species were identified. Correlation analysis between microbial genera and key flavor compounds, showing stronger associations during the early stages of fermentation. KEGG pathway analysis demonstrated that the formation of flavor compounds was closely associated with organic acid and amino acid metabolism. Moreover, several microbial taxa were identified as key contributors to the biosynthesis of specific flavor compounds. • Multi-omics revealed key flavor development patterns in Wei Fan Jiu fermentation. • 64 volatiles and 39 non-volatiles were found; 17 key compounds were screened by OAV/VIP. • Fungi, mainly Saccharomyces , Aspergillus , and Rhizopus , dominated and shaped flavor. • Pearson’r showed links between microbes and flavors. • KEGG analysis identified yeast- and Pediococcus -driven pathways for flavor compound synthesis.