对乳酸链球菌和酿酒酵母菌进行混合培养发酵，通过讨论溶氧、温度、pH值、接种量、接种比例和培养基对其发酵结束时活菌数的影响，确定两种菌在前期28℃摇床150 r/min培养24 h，后期37℃静置24 h，初始pH为7．5，接种量为0．5％，接种比例乳酸菌∶酵母菌为1％∶0．5％，培养基为YEPD时，两者的活菌数水平达到最高值，乳酸菌达5．0×10 CFU/mL，酵母菌达1．0×108 CFU/mL。8%Lactococcus lactis and Saccharomyces cerevisiae were cultivated and fermented together , and the impacts of dissolved oxygen, temperature, pH value, inoculum size, inoculation proportion, and culture medium on the number of viable count at the end of their fermentation were investigated .The optimized mixed culture conditions for these two bacteria were obtained as follows :culture for 24 hours in shaker at 150 r/min at 28 ℃in earlier period, stewing for 24 hours at 37 ℃in later period, the initial pH value was 7.5, the inoculum size was 0.5%, the inoculation ratio of lactic acid bacteria to yeast was 1%∶0.5%, and the culture medium was YEPD.Under these conditions, the number of viable count of lactic acid bacteria and yeast reached the highest value , being 5.0 ×10 8 and 1.0 ×10 8 CFU/mL respectively.
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