Primary exploration of fermenting the bean dregs and yellow serofluid by Lactobacillus rhamnosus to produce L-lactic acid

MRS Broth was substituted by bean dregs and yellow serofluid gradually.The rich nutrition of bean dregs and yellow serofluid as a medium, and Lactobacillus rhamnosus which could extensively grow and only produce L-lactic acid was chosen as fermentation strains. To select the optimal proportion of bean dregs and yellow serofluid by taking the viable count, pH value, L-lactic acid content as the characteristic index. A primary discussion for this production process was progressed according to the result of experimentation. The results showed that Lactobacillus rhamnosus could fully adapt to grow in bean dregs and yellow serofluid. A maximum L-lactic acid content of 1.07% was obtained under the following optimized fermentation conditions: bean dregs/yellow serofluid ratio 1∶5, 3% vol inoculum, 4% glucose, pH6.2, fermentation time 24h at 37℃.