Effects on product formation in Lactococcus lactis 65.1 in continuous culture with complete cell recycling

Lactococcus lactis 65.1 was cultivated in a batch culture, which underwent starvation for 3 days, continuous culture and continuous culture with complete cell recycling. The objective was to study the product formation and intracellular protein pattern. Changes from homofermentative to heterofermentative metabolism were observed in continuous culture at the lower dilution rates as well as continuous cultures with complete cell recycling at a fixed dilution rate (D=0.4 h^–1). Changes in intracellular protein pattern were observed when starving the cells in a batch culture and also when recycling the cells in a continuous culture. Some changes were the same in these two cases. The data collected from these experiments show how the fermentation technique can affect the products of the microorganism being cultured and gives some interesting information on the complete cell recycling technique, which is of great interest in fermentation processes.