Short communication Estimation of viscosity of highly viscous fermentation media containing one or more solutes

Viscosity and density data are collected at different temperatures for aqueous solutions of glucose, carboxymethyl cellulose (CMC), or both the solutes and used to check the form of a predictive model proposed in this study for viscosity estimation of mixtures of nonelectrolyte solutes in Newtonian fermentation broths. The model, which derives from the well-known Guzman±Andrade equation and is based on the Eyring theory, supposes a separate contribution of each solute to total viscosity, which linearly increases with solute concentration and exponentially decreases with temperature. Percentage deviations between theoretical and experimental viscosity values of both, the binary and ternary mixtures, are usually <5%, thus con®rming the validity of the present approach. # 1999 Elsevier Science S.A. All rights reserved.