Community assembly and aroma contribution of Hanseniaspora yeasts in spontaneous fermentation of Cabernet Sauvignon grapes from four regions in Northwest China

This study investigated the community assembly and aroma contribution of Hanseniaspora yeasts during spontaneous fermentation of Cabernet Sauvignon grapes from four regions (Zhangye, Wuhai, Yinchuan, and Xianyang) in Northwest China. The resulting wines were characterized by distinct profiles of volatile compositions and aroma characteristics. High-throughput sequencing identified Hanseniaspora as the most abundant non- Saccharomyces community during fermentation, while culture-dependent isolation of 138 Hanseniaspora strains showed differential community assembly of H. uvarum , H. opuntiae , H. osmophila , and H. vineae across regions. H. osmophila and H. vineae were notably enriched in high-sugar musts from Zhangye, Wuhai, and Yinchuan with high diurnal temperature range. Such enrichment may induce longer survival of Hanseniaspora community at later fermentation stage, giving wines higher levels of acetate ester and floral aroma. Partial least squares regression of Hanseniaspora species and volatile compounds further suggested the potential impact of H. osmophila on region-driven variation in acetate ester production. • Hanseniaspora was the most abundant non-Saccharomyces yeast in all four regions. • Culture-dependent methods revealed region-specific assembly of Hanseniaspora species. • High-sugar musts from regions with high ADTR enriched H. osmophila and H. vineae . • PLSR confirmed the strong correlation of H. osmophila with acetate esters.