WANG Qiuju;XU Li;GUI Yizhe

College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China;op-server.unil.ch

yeast culture;fermentation;temperature;acidity;cell-wall broken

Culture condition of every phase for fermentation of yeast culture was studied, and its solid and liquid conditions of elaboration were optimized to improve the total counts of living cells. Results showed that microzyme grew best at 30°C when solidfermented, and the count of the living cells reached the tiptop with pH 5.5. The count of Candida tropicalis could reach 137.96x10~9 cfu-g~(-1), the count of Saccharomyces cerevisia could reach 134.62x10~9cfu - g~(-1); the best liquid fermentation condition for cell-wall broken was 50 °C for 28 h, the rate of cell-wall broken could reach 80% at least; the rate of vitamin loss in yeast could be the minimun, the loss rate of vitamin B_1 in Candida tropicalis and Saccharomyces cerevisiae was 8.71% and 19.54% respectively, the loss rate of vitamin B_2 was 19.39% and 13.18%, respectively, and the loss rate of vitamin B_6 was 6.3% and 3.04%, respectively.