Growth and Fermentation Model for Alginate‐Entrapped Saccharomyces cerevisiae

A model of growth and fermentation for alginate‐entrapped Saccharomyces cerevisiae is presented. The model is based on Peringer's rate equations (Peringer, P.; et al. Biotechnol. Bioeng. Symp. 1973 , 4, 27–42), developed for glucose‐repressed cultures of suspended cells at varying dissolved oxygen concentrations, and was fitted to estimates of growth and fermentation rates for immobilized cells obtained through a combination of experimental measurements and reaction‐diffusion analysis. Immobilized cell fermentation data with alginate beads in suspension compared well with simulations of reaction and diffusion in a similar system incorporating the proposed growth‐fermentation model. In view of these findings, the model was further applied to the simulation of transient and steady‐state operation of a packed‐bed immobilized cell biore‐actor. Results about the effect of operating parameters on bioreactor performance are presented, and implications regarding system design and operation for optimal overall performance are discussed.