Quality Characteristics and Fungal Diversity during Natural and Inoculated Fermentation of "Hutai 8" Wine

In order to increase the added value of table grape products and consequently improve the income of fruit farmers, this experiment systematically studied the relationship between fungal diversity and "Hutai 8 " wine quality during the winemaking process. Fungal diversity changes during natural and inoculated wine fermentation were studied by high-throughput sequencing, and changes in flavor characteristics were evaluated as well. The results showed that compared with inoculated fermentation, naturally fermented wine had lower alcohol content and higher acetic acid content. Moreover, the contents of volatile alcohols and esters were higher than those of the wine produced by inoculated fermentation, and the content of fatty acids was lower. At the early stage of natural fermentation, Hanseniaspora was dominant in the microbial community of naturally fermented wine, a large number of Saccharomyces appeared at the middle stage, and there were still a large number of Hanseniaspora at the late stage. S. cerevisiae remained dominant during inoculated fermentation. Ethyl acetate and some alcohols, such as benzyl alcohol, benzyl alcohol, hexanol, cis-3-nonene-1-ol, were correlated with the genera Alternaria, Acremonium and Cladosporium. In addition, there could be a risk of naturally fermented "Hutai 8" wine deteriorating and producing a large amount of ethyl acetate, which can adversely affect the aroma. Therefore, inoculated fermentation is recommended to produce "Hutai 8" wine.