Isolation And Identification Of Yeast In Koumiss And Study On Alcohol Content Variation In Fermentative Koumiss

In this paper , 37 strain yeasts were isolated from 4 regions of 8 samples of koumiss . Generic Identification were researched:â‘ Morphology:Colony forms,Cells forms, Vegetative reproduction,Ascus spore,Ballistospore;â‘¡biochemistry:Nitrate electronation reaction, Starch of kind material production Urea enzyme experiment,Sugar fermentatation experiment, Carbonaceous assimilation experiment,Azote assimilation experiment. According to ?Handbook of property and identification of yeast? , they are included 6 Generics , 11Kinds,as follows : 2 strain Saccharomyces are Saccharomyces cerevisiace; 8 strain Candida include 2 strain Candida fennica and Candida vini ; 4 strain Kloeckera are Kloeckera lindneri ; 10 strain Brettanomyces include 1 strain Brettanomyces anomalus, 1 strain Brettanomyces claussenii and 8 strain Brettanomyces custersianus ; 1 strain Torulaspora is Torulaspora delbrueckii; 4 strain Dekkera are Dekkera bruxellensis; 7 strain Kluyveromyces are Kluyveromyces marxianus; 1 strain Pichia is Pichia humboldtii.we chose 3 strains to make the koumiss by carrying on the mixed fermentation under the experimental condition with the lactic acid bacteria. In fermentative process we measured alcohol content variation. The results indicate the alcohol content is gradually going up in fermentative process, and the yeast influence the alcohol content, the acidity and the flavor. The fermentative ability among these 3 strains and their combinations are also different. And by measuring the count of the living-yeast in mature koumiss,we can know the growth of yeast in koumiss under low temperature.