IMPROVEMENT OF LACTIC CELL PRODUCTION

The production of Lactobacillus brevis has been improved by changing t he medium composition and the physiological conditions. The cellular c oncentration reaches 8.2 x 10(10) cells/mL in 21 h with a fed-batch te chnique in MRS medium. Freeze-drying has been used as technology for d rying the cells and survival rates have been improved with different a dditives such as glycerol, CaCO3, and skimmed-milk powder up to 70%. A model has been developed to predict the stability of freeze-dried cul tures during long-term conservation. This model, based on Arrhenius eq uation, has been confirmed by experimental data.