CONTROL OF CELL AND LACTATE CONCENTRATION IN A HOLLOW-FIBER BIOREACTOR FOR LACTIC ACID FERMENTATION

Abstract

From the amount of alkaline solution supplied for neutralizing the broth, lactate concentration was estimated on line in the fermentation of Streptococcus cremoris. Cell concentration in the broth was also monitored on line using a turbidimeter. The monitoring system was applied to the culture accompanied by filtration, and both cell and lactate concentrations were controlled at constant levels by on-off control. In this culture, cells and lactate were continuously produced at constant rates, and the concentrations in the fermenter were kept constant.