Precise knowledge of the viscosity of yeast suspensions is essential to the design of many recovery operations. The present work is concerned with measurement of the viscosity of Saccharomyces cerevisiae and Candida utilis suspensions at different cell concentrations and osmotic pressures. Particular attention is given to the determination of the volume fraction ∈X of the yeast suspensions.
The experimental results may be correlated by an equation of the form
Parameter ‘a’ depends on the morphology of the yeast whilst hS is a function of the osmotic pressure. The latter dependency is interpreted through the concept of close packing of the microbial particles.