Microbial community dynamics in spontaneous fermentation of Vitis quinquangularis Rehd. Wine across Southwest China: Correlations with volatile compounds

Geographical origin strongly influences microbial community composition during spontaneous wine fermentation, shaping the aromatic profiles of the final product. Vitis quinquangularis Rehd., a native East Asian grape species, thrives in the hot, humid climate of Southwestern China. However, little is known about how regional differences affect microbial dynamics and aroma development during its spontaneous fermentation. In this study, V. quinquangularis wines from two wine-producing regions were analyzed using high-throughput sequencing and HS-SPME/GC-MS to examine microbial diversity, community dynamics, and their contributions to volatile composition. Microbial diversity varied significantly among musts from different vineyards and played a pivotal role in shaping the distinct volatile profiles observed in the resulting wines. Alcoholic fermentation was primarily driven by Saccharomyces sp. in one region and Schizosaccharomyces japonicus in the other. Correlation analysis showed that microbial species active during early fermentation stages strongly influenced the development of volatile compounds. These findings improve understanding of the terroir characteristics of V. quinquangularis Rehd. wines and highlighted the importance of conserving regional microbial biodiversity to support sustainable viticulture and winemaking in Southwest China.