Research on Fermenting Properties of Natural Excellent Wine Yeast

16 wine yeast strains preserved in the Lab were used as test strains.Preliminary screening was carried out through simulating alcohol fermentation and 5 strains with good fermenting power or good aroma-producing capability were obtained.Other 2 commercial strains were used as contrast strains.Their resistance to NaCl,SO2,alcoholicity,pH,temperature,and high sugar were measured by Durham tube method.The results showed that all the strains could ferment and produce gas when the concentration range of SO2 was from 200.0 mg/L to 600.0 mg/L and glucose concentration was from 400 g/L to 600 g/L,and they grew well at pH from 1.5 to 13.0.Among them,five strains could tolerate 100 g/L NaCl and 22 % alcohol at the most,and two strains could tolerate high temperature up to 70 ℃.Wine-making results showed that strain Y-6 produced alcohol in higher degree and total acids and volatile acids in lower degree than other two commercial yeast strains,besides,it could enhance stronger aroma in wine and make wine taste more harmonious.Accordingly,it was suitable for grape wine production in practice.