Mathematical description of ethanol fermentation by immobilised Saccharomyces cerevisiae

Fermentation characteristics of Saccharomyces cerevisiae ATCC 9763 immobilised in Ca-alginate gel beads have been investigated in a stirred batch system at 2, 4, 8, 10% (w/v) initial glucose concentrations. The experimental results were tested using eleven different kinetic models relating biomass and ethanol production and glucose utilisation in different forms. The models proposed by Monod and Hinshelwood were found to be more appropriate for describing the batch growth and ethanol production of immobilised S. cerevisiae at low (2-4%) and high (8-10%) initial glucose concentrations, respectively. The validation of the models chosen was done using data obtained from experiments in an inclined reactor with nutrient recirculation. (C) 1998 Elsevier Science Ltd. All rights reserved.