Comparative study of microbial communities and volatile profiles during the inoculated and spontaneous fermentation of persimmon wine

Abstract

In this study, we determined the composition of microorganisms in the spontaneous/inoculated fermentation process of persimmon (Diospyros kaki L., China) wine for the first time and compared the similarities and differences of microbial succession, change in volatile compounds, and variations in amino acids. We found that spontaneous persimmon wine fermentation (SPF) resulted in lower bacterial community diversity and higher fungi community diversity than inoculated persimmon wine fermentation (IPF). SPF increased the proportion of esters in overall volatile compounds (29.9 % vs 18.9 %) at the end of fermentation. According to partial least squares (PLS, VIP > 1.0) analysis and Spearman’s correlation analysis, 18 (11 bacterial and 7 fungus) were identified as the functional core microbiotas in SPF. Among them, indigenous Saccharomyces, Hanseniaspora, Rhodotorula, Leuconostoc, and Lactobacillus play an important role in the formation of volatile compounds and are worthy of further study, while Escherichia-Shigella, Ralstonia and Zoogloea should be inhibited during the fermentation process. However, a key problem in SPF was the fermentation time, which was too long (about 27 days) and did not meet the needs of industrial production. Overall, the results showed the possibility of considering select indigenous aroma-producing microorganisms as persimmon wine fermentation starters to improve the unique characteristics of persimmon wine.