Abstract:

In order to obtain the proliferation medium of streptococcus thermophilus and Lactobacillus bulgaricus, on the basis of MRS medium added different nutrients to the influence of lactic acid bacteria growth, and further optimized by orthogonal test screening. The results showed that the appropriate growth conditions were determined as: improved MRS as basic medium, with an addition of 1% carrot juice, 1.5% wort, 0.5% soybean juice, KH2PO4-Na2HPO4 (pH 6.86) solution was spiked into the mash with a 2 h interval after 10 h fermentation at 42-45℃, and cultured for 16 h, the number of viable cells of lactic acid bacteria 3.94×109 cfu/mL, increased 11.6 percent higher than before. The effect of lactic acid bacteria proliferation was not satisfactory, needed to continue to explore effective nutritional enhancement factor.