Different strains of brewing yeast were separated from natural berries and classified according to physiological and biochemical identification,then,fermentation process was carried out to screen most suitable natural yeast of red raspberry wine. First of all,30 strains of yeast strains were isolated from different sources of fresh raspberries,grapes,blueberries,and divided into 25 kinds by use of morphological and physiological and biochemical identification methods. No. 33 brewing yeast was screened out t...