Kinetic models and effect of temperature on ethanol production in batch fermentation by Saccharomyces cerevisiae strain

The effect of temperature from 25℃ to 37℃ on ethanol production in batch fermentation of sweet sorghum stalk juice by immobilized Saccharomyces cerevisiae was investigated. In addition, kinetic models were studied. The result shows that cell growth is hastened with the increase of temperature, but too high temperature has a negative influence on the cell growth, and the ethanol yield will be decreased. Hinshelwood equation was successfully applied to estimate the kinetics of cell growth and ethanol production. The kinetic parameters at different temperature from 25℃ to 34℃ were obtained. Based on the estimated parameters, the effect of temperature on the kinetic parameters of cell growth was further studied. An equation was developed and applied to interlink the relationship between yeast cell concentration and temperature as well as substrate concentration in the process of ethanol production in batch fermentation. The experimental results showed that this model could predict the growth pattern very well.