Research On Selecting Excellent Yeast And Biological Characteristics From Strawberry In Hohhot

This experiment collected HongYan and SuiZhu two varieties of strawberries from Hohhot, a total of 40. After enrichment culture, they can be isolated 67 strains of yeast, then using the conventional taxonomy and WL medium to separate preliminarily for yeast. The representative yeasts are selected by the study on biological characteristics and fermentation of yeast trials. The last step is selecting best yeast to identify ITS region.The results showed that selecting four genera yeast from strawberry in Hohhot which by preliminary taxonomy. They are Clavispora、Hans enula、Torulaspora and Rhodotorula; including four kinds:Clavispora lusitaniae、Hansenula anomala、Torulaspora debrueckii and Rhodotorula glutinis.12 most typical strains screened for biological characteristics of the test. It turns out that the strain of H3 and H16 have an excellent biological feature, especially the H16,which can survived at the lowest temperature of 10℃, the highest temperature of 42℃, the alcohol concentration is 12%, pH is 1.5, the sugar concentration is 60% and SO2 concentration is 400mg/L. The tests of the alcohol fermentation on H3 and H16 turns out that the alcohol concentration of H16 is 10.3% and H3 is 8.2% after 10 days, which means that H16 is better than H3 in the alcohol fermentation test. H16 is 2.2 and the strain H3 is 3.5 after 10 days which means that H16 sugar content decreased faster than H3 in residual sugar experiment. Above all, strain H16 is the best yeast of strawberry from east region of Hohhot in Inner Mongolia.It can be analyzed by the system of the evolutionary tree on ITS region, the results shows that the best yeast strain is H16, which means Clavispora lusitaniae.