Effect of sequential fermentation with four non-Saccharomyces and Saccharomyces cerevisiae on nutritional characteristics and flavor profiles of kiwi wines

To improve the functional properties and flavor complexity of kiwi wine using different non-Saccharomyces cerevisiae, Wickeramomyces anomala (Wa), Zygosaccharomyces rouxii (Zr), ZygoSaccharomyces bailii (Zb) and Schizosaccharomyces pombe (Sp) were inoculated sequentially with S. cerevisiae (Sc). The physicochemical and sensorial profiles of the wines were evaluated. The evolution of cells showed that non-Saccharomyces exhibited varying degrees of fermentation vigor and only acted during the first vinification stage. Ethanol content, pH, ΔE and organic acids in the wines varied according to the yeasts used. Compared with the pure Sc fermentation, the sequential fermentations of Wa-Sc and Sp-Sc significantly increased the production of polyphenols. Fifteen volatile compounds with relative odor activity values (rOAV) ≥ 1.0 were identified. Furthermore, principal component analysis (PCA) revealed that Zr-Sc and Sp-Sc were correlated with higher levels of ethyl esters (ethyl hexanoate, ethyl heptanoate, ethyl decanoate), isoamyl acetate and 2-phenyl-1-ethanol in the wines, improving the flower and sweet notes. Zr-Sc also enhanced the tropical fruity aroma. Sequential inoculation with Zb was related to the contents of acetate esters, ethyl butyrate, methyl butyrate and cineole, triggering the tropical fruity odor. In addition, the partial least-squares regression (PLSR) revealed that acetate esters contributed greatly to the tropical fruity note.