ONLINE MEASUREMENT AND CONTROL OF CELL CONCENTRATION OF SACCHAROMYCES-CEREVISIAE USING A LASER TURBIDIMETER

Abstract

On-line measurement and control of cell concentration of Saccharomyces cerevisiae using a laser turbidimeter was carried out. Effects on the turbidity measurement of operating parameters such as agitation speed, aeration rate, and the concentration of antifoam agent were investigated. Correlations between the on-line-measured turbidity and the off-line dry cell weight concentration were made at various operating conditions. Using the correlations the cell concentration was successfully estimated in a range of up to 8 g/L in batch cultures. The on-line monitoring and regulation of the cell concentration in a range of up to 35 g/L were also satisfactory in continuous and turbidostat cultures with cell recycle.