Characterization of aroma active compounds and microbial communities in spontaneously fermented Vitis quinquangularis wines.

This study comprehensively investigated volatile compounds and microbial communities of spontaneously fermented Vitis quinquangularis wines from the Guangxi production regions. The aroma profiles of V. quinquangularis wines were analyzed by GC-O-MS, GC-QQQ-MS/MS, and quantitative descriptive analysis. The wines exhibit predominantly fruity and floral notes, with contributions from esters and (E)-β-damascenone. A distinctive and typical "green and earthy" aroma was observed, with contributions from C6 compounds and volatile phenols such as 1-hexanol, (E)-3-hexen-1-ol, hexanoic acid, 4-vinylguaiacol, eugenol, and isoeugenol. Metagenomics and culturomics analyses indicated that the dominant strains involved in the spontaneous fermentation process were Hanseniaspora opuntiae, Saccharomyces cerevisiae, Paenibacillus sp., Sphingomonas sp., and Bacillus sp. Additionally, microorganisms from sixteen generas, including Actinomycetospora and Ameyamaea, etc., along with six enzymes like EC 1.1.1.1 and EC 1.1.1.318, etc., were implicated in the production of the "green and earthy" aroma in V. quinquangularis wines.