Fermentation Kinetics of Different Sugars by Apple Wine YeastSaccharomyces cerevisiae

Abstract

A non-linear kinetic model to predict the consumption of different sugars (glucose, fructose and sucrose) as a substrate, during an apple wine yeast fermentation with Saccharomyces cerevisiae strain CCTCC M201022 is proposed. This model was used to predict sugar utilization by this yeast beginning at various initial sugar concentrations. After observation of the experimental data, a model based on the logistic equation of yeast growth, growth-associated production of ethanol with a lag time, and consumption of sugars for biomass formation and maintenance, was developed. After experimental model fitting, kinetic parameters in the model were estimated. The experimental verification of the model was performed using flask-scale fermentations, and the model obtained predicted the fermentation performance effectively, using different sugars as the substrate set at various initial sugar concentrations. Based on estimated kinetic parameters and the characteristics of sugar utilization, the yeast examined appeared to be glucophilic. The effects of different sugars with various initial concentrations on the fermentation performance by this yeast were investigated, and some applications of kinetic parameters are discussed.