Application of a Statistical Technique to Investigate Calcium,Sodium, and Magnesium Ion Effect in Yeast Fermentation

In this work, the dependence of the ethanol production using Saccharomyces cerevisiae 251TP(3-2) on calcium, sodium, and magnesium ion concentration and interaction effects were studied with the use of a statistical experimental design. The parameters of the ethanol concentration model proposed on the basis of Box–Wilson experimental design method were evaluated with the use of the experimental data. Comparison of the predicted values from the model with the experimentally observed values showed that the model is a good fit. From the analysis of model equation, it was seen that sodium ion concentration has significant main effects on ethanol production, and there is interactive effect only between calcium and magnesium. With the use of developed model, maximum ethanol concentration of 3.73% (v/v) was obtained when calcium, sodium, and magnesium concentration were 1,515, 930, and 128 mg/L, respectively, for the 10% sugar concentration in synthetic molasses.