Dynamic changes in microbial communities and flavor components of Cupei during fermentation of Shanxi mature vinegar via multiomics analysis

BACKGROUND: The quality of traditional Shanxi mature vinegar (SMV) is closely associated with the characteristics of Cupei (vinegar grains). This study integrated high-throughput sequencing and metabolomics to investigate microbial succession and flavor metabolite dynamics during Cupei fermentation. RESULTS: A total of 7 organic acids, 17 amino acids, and 112 volatile compounds were identified. Acetobacter, Lactobacillus, Weissella, Streptococcus, Bacillus, Issatchenkia, and Aspergillus were identified as dominant microbial genera. Multiomics association analysis revealed significant associations between certain microorganisms, particularly Issatchenkia and Weissella, and specific volatile compounds. Lactic acid, acetic acid, and fumaric acid were significantly correlated with multiple microbial genera, although these associations were not observed for Massilia and Aspergillus. Furthermore, Lactobacillus and Acetobacter exhibited distinct correlation patterns with amino acids, suggesting their potential involvement in amino acid metabolism during fermentation. CONCLUSION: This study provides insights into the relationships between microbial succession and flavor metabolite dynamics during SMV Cupei fermentation. These findings may contribute to a better understanding of the fermentation process and inform future strategies for improving SMV aroma and quality. © 2026 Society of Chemical Industry.