Abstract:The aroma of kiwifruit wine is closely dependent on the yeast strains used for fermentation. In this study, yeast strains were isolated from kiwifruit peel, and strains suitable for kiwifruit wine fermentation were obtained after purification, screening, and identification. The effects of the screened strains on the aromatic composition and content of kiwifruit wines were determined by gas chromatography coupled with mass spectrometry (GC-MS). The results showed that two screened yeast strains (1-21 and 1-31) were identified as Saccharomyces cerevisiae (baker’s yeast) and Issatchenkia orientalis, respectively, by using 26S rDNA sequencing. Compared with the commercially available yeast strain, the screened yeast strain 1-21 showed a stronger fermentation capacity, stronger acid resistance, and produced higher ascorbic acid content in wine. In contrast, strain 1-31 was more resistant to high sulfur dioxide concentration and produced a unique aroma in wine. By comparison, characteristic differences in the aromatic composition and content were found in the kiwifruit wines fermented using different yeast strains. Among the 49 identified aromatic compounds, 13 were common aromatic components, eight were only found in the kiwifruit wine fermented using strain 1-21, and seven were only found in the kiwifruit wine fermented using strain 1-31. In addition, the aromatic compound content in kiwifruit wines fermented using the screened strains was significantly higher than that in kiwifruit wine fermented using a commercially available yeast strain. Therefore, the screened yeast strains 1-21 and 1-31 were considered more suitable for producing the characteristic aroma of kiwifruit wine.
