Characteristic Aroma Screening among Green Tea Varieties and Electronic Sensory Evaluation of Green Tea Wine

Green tea is a non-fermented tea with flavor and polyphenols. Aroma is one of the important quality indicators of tea. Fermented green tea wine can solve the problem of low-grade tea, which has more bitterness and less aroma. In this study, Camellia sinensis var. pubilimba Hung T. Chang (Kaishan white tea 2) was screened by orthogonal partial least squares-discriminant analysis (OPLS-DA) to benzyl alcohol and phenethyl alcohol presenting a fruity aroma, dimethyl sulfide presenting a green tea aroma, and rich tea polyphenols with contents of 2.08, 2.43, 12.26 and 3.72%, respectively. The optimal fermentation conditions for green tea wine were determined univariately as 1.5% yeast addition, 30 °Brix initial sugar, and fermentation temperature of 25 °C. The electronic sensory assessment showed that the saltiness, richness and umami were more prominent in green tea wine, while the response values of bitterness, astringency and aftertaste-A were lower. The order of aroma contribution can be seen as W1S > W5S > W2S > W2W > W1W > W3S > W6S. Kaisan white tea 2 gives green tea wine a clear tea aroma. This study provides better technical and theoretical strategies for the comprehensive quality assessment and control of fermented green tea wine quality.