An optical sensor for on-line biomass monitoring was developed and implemen
ted with a how-through cell and a continuous sampling line to monitor cell
concentrations in solutions of water and diluted molasses. Calibration curv
es, errors curve, how rate effects and measurements comparing obtained valu
es using the optical sensor and dry cell weight method were analysed. The c
alibration curves using cell cultures in tap water and molasses present an
exponential profile in the range 5-40 g cell 1(-1) corresponding to 0-250 m
V output signal. The output signal for biomass free molasses solutions was
used for reference and compensation effects. A simple correlation for molas
ses compensation was determined and good reproducibility was obtained betwe
en experimental and calculated values for a wide range of biomass-molasses-
water solutions. (C) 2001 Elsevier Science B.V. All rights reserved.