Mathematical Model for a Tequila Batch Fermentation

A nonlinear kinetic model was elaborated to predict the tequila fermentation process. Triplicate shake flask agave juice fermentations essays at constant temperature were done, using different substrate concentrations and Saccharomyces cerevisiae yeast isolated from the agave juice. An increase in substrate concentration produces also an increase in the ethanol concentration; however, this relationship is nonlinear. Substrate and product inhibitions were detected and affected the specific growth rate. A mathematical model taking into account substrate and product inhibition was proposed and validated. The model showed a satisfactory prediction on substrate and ethanol behavior; however, new approaches have to be done to predict the biomass accurately.