Isolation,Identification,Fermentation Characteristics and Volatile Aroma Components Analysis of non-Saccharomyces for Tangerine Wine

Objective:To obtain the non-Saccharomyces suitable for the tangerine wine.Methods:The aroma-producing yeasts isolated from spontaneous fermented Nanfeng tangerine wine were identified by the analysis of 26S rDNA sequences.On the basis of the aromatic profiles analysis of tangerine wine by headspace-gas chromatography-mass spectrometry(HS-GC-MS)and taking the residual sugar,ethanol production,total acids and pH of tangerine wine into account,the strains which exhibited excellent characteristics and produced abundant aroma compounds were screened out. Results:A total of 7 strains of aroma-producing yeast were isolated and identified as Pichia fermentans,Pichia aff. fermentans,Pichia kluyveri,Hanseniaspora guilliermondii,Hanseniaspora opuntiae,Hanseniaspora thailandica and Candida ethanolica. C. ethanolica exhibited excellent characteristics of tangerine fermentation,which could make wine contained more ethanol(8.9%)and less residual sugar(1.2 g/L). H. thailandica produced abundant aroma compounds with less fusel alcohols and acids,more esters such as ethyl acetate,ethyl menthyl acetate,ethyl laurate,ethyl octanoate,phenylethyl acetate,ethyl propionate,lactic acid,ethyl ester,which could weaken the bitter taste,coordinate the bitter taste,make the wine mellow,and had a good sensory evaluation. Conclusion:It was found that C. ethanolica and H. thailandica exhibited excellent characteristics and produced abundant aroma compounds for tangerine wine fermentation,respectively.These results would lay a foundation for mixed fermentation to improve the flavor of tangerine wine in future.