A Method of using off-line Measurements in an On-line Estimator of Biomass Concentration for a Penicillin Fermentation, and its Effects on the Quality of the Estimates

Abstract

A method of improving on-line estimation of the biomass concentration for a fed-batch penicillin fermentation, by using the information available in off-line measurements of biomass concentration, is presented. The on-line estimator was based on a well known, two parameter model that relates respiratory activity, in the form of carbon dioxide evolution rate measurements, to growth and non growth associated culture activities. The off-line measurements were used to identify one of the model parameters. In an illustrative example, estimation is shown to be improved using off-line measurements that are delayed by up to 24.5 hours. The quality of the estimation was found to decrease with increasing analysis delay.