A reduced specific ethanol‐forming performance of yeast at high biomass concentrations as a result of a changed ethanol‐tolerance behaviour of the cells under condition of limitation. II. Proving the effect in high‐flow rate fermentations with saccharomyces cerevisiae Sc 5

In growth‐factor limited fermentations carried out in continuous high‐flow rate fermenters the relationship existing between the specific ethanol formation rate and the ethanol concentration was found to change its characteristics from a linear function into a nonlinear one at high biomass concentrations. The deviation from the linear inhibitory behaviour of the cells was the greater the more the biomass concentration increased. A very good correspondence between the experimentally found productivities of ethanol formation and its adequate values obtained by calculation could be attained by using an improved steady‐state productivity model, in which the variability of the function v = f(P) had been considered.