High-concentration cultivation of Lactococcus cremoris in a cell-recycle reactor.

High-cell concentration cultivation of Lactococcus cremoris, a homofermentative lactic acid producer, in a cell-recycle fermentor is described. Cross-flow filtration allowing continuous removal of the inhibitory metabolite, the influence of dilution rate on growth was investigated in total or partial cell-recycle cultures. The dependence of growth characteristics on operating conditions was identified and quantified using lactose as the carbon source.