Kinetics of riboflavin production by Brewers' yeasts

The kinetics of riboflavin production by Saccharomyces cerevisiae and Saccharomyces carlsbergensis in synthetic media and wort were studied. The results indicated that riboflavin was produced by growing cells only. Riboflavin production rate was proportional to growth rate of the yeasts in the exponential phase. Riboflavin was depleted in the stationary phase. The depletion rate was expressed with a first-order kinetic expression in yeast concentration. The kinetics of substrate utilization and ethanol production were also given to describe better the associated phenomena and fermentation pattern.