STUDIES ON THE GROWTH AND ACID PRODUCTION OF PURE AND MIXED CULTURES OF BIFIDOBACTERIUM BIFIDUM, LACTOBACILLUS ACIDOPHILUS AND LACTOBACILLUS BULGARICUS

摘要

Growth and acid production of Bifidobacterium bifidum, Lactobacillus acidophilus and Lactobacillus bulgaricus separately and in combination were investigated. Fermentations were run at 40 and 45℃, with inocula of 3 and 5% in cow's milk and milk media containing glucose and tomato juice. Comparing the fermentations, the mixed cultures (B. bifidum + L. acidophilus and B. bifidum + L. bulgaricus) resulted in higher acidity and cell count than the single cultures. Addition of the tomato juice to the milk media had a more significant effect on growth and acid production than the addition of 1% glucose. Increasing the inoculum from 3 to 5% increased the acidity and cell count. Comparing the effect of fermentation temperature, growth and acid production rates at 45℃ were higher than those at 40℃.