Effects of Different Fermentation Methods on the Quality and Microbial Diversity of Passion Fruit Wine

Passion fruit wine is a popular fruit wine because of its unique aroma. However, the roles of microorganisms in different fermentation methods, particularly their contributions to aroma formation, are poorly understood. Accordingly, the goal of this study is to reveal the contribution of different fermentation methods to the flavor. Purple passion fruit was used as the experimental focus; high-throughput sequencing technology was used to analyze the microbial community of CF (controlled fermentation) and NF (natural fermentation), and the correlations between the microbial community and physicochemical indices, nonvolatile metabolites and flavor substances were analyzed. In NF, totals of eight fungal phyla, 135 fungal genera, 15 bacterial phyla and 130 bacterial genera were identified. Debaryomyces, Meyerozyma, and Wickerhamomyces were the dominant fungal genera, and Paucibacter and Pantoea were the dominant bacterial genera. In CF, totals of 11 fungal phyla, 389 fungal genera, 15 bacterial phyla and 128 bacterial genera were identified. Meyerozyma, Cladosporium, and Saccharomyces were the dominant fungal genera, and Paucibacter, Achromobacter, and Lactobacillus were the dominant bacterial genera. In NF, Wickerhamomyces, Achromobacter, Bifidobacterium and Lactobacillus were positively correlated with flavor substances such as ethylene glycol acetate formate, 2-pentanol, acetate, phenylethyl alcohol and 1-butanol, 3-methyl-. In CF, Saccharomyces, Achromobacter and Lactobacillus were positively correlated with a variety of esters and alcohols such as decanoic acid, ethyl ester, dodecanoic acid, ethyl ester and phenylethyl alcohol. Overall, this study can provide a valuable resource for further developments and improve the aromatic quality of passion fruit wine.