High dilution rate and high cell density continuous lactic acid production by Lactococcus lactis IO-1 in hydrolyzed sago starch medium was investigated using a pH-dependent feed system coupled with cross flow filtration and turbidity control. Lactate production and productivity were dependent on cell density, dilution rate and feed glucose concentration. At a cell concentration of 15 g/l and a feed glucose concentration of 50 g/l, volumetric lactate productivities of 14.9, 23.5 and 33.0 g · l-1 · h-1 were obtained at dilution rates of 0.35, 0.5 and 1.1h-1 respectively. The respective residual glucose concentrations in the permeate were 0.8, 1.0 and 3.7 g/l. On increasing the feed glucose concentration to 64 g/l, volumetric lactate productivities of 12.4 and 32.3 g · l-1 · h-1 at dilution rates of 0.21 and 0.70 h-1 were obtained while the respective residual glucose concentrations in permeate were 2.7 and 12.2 g/l.
|Number of pages||9|
|Journal||Journal of the Faculty of Agriculture, Kyushu University|
|Publication status||Published - Feb 2000|
All Science Journal Classification (ASJC) codes
- Agricultural and Biological Sciences (miscellaneous)