OPTIMIZATION OF THE FERMENTATION OF WHEY BY LACTOBACILLUS-CASEI

Optimization studies have been carried out for the production of L-lactic acid from the fermentation of whey by Lactobacillus casei. Two Statistical Designs, a full 2(4) Factorial Design and a full 3(2). Factorial Design, have been used to determine the most suitable values of the operational variables for obtaining the maximum lactic acid production rate. The variables selected for study were temperature, pH, lactose concentration, and inoculum concentration. Among them only temperature and pH were found to affect the response significantly. A second-order polynomial empirical model relating both the response (lactic acid production rate) and the variables was formulated. The maximum acid production rate was found when the values of pH and temperature were 5.4 and 38-degrees-C, respectively. All conclusions are restricted to the experimental range studied.