Optimization of Baker’s Yeast Production on Grape Juice Using Response Surface Methodology

The purpose of this study is to complete as an example the fermentation conditions allowing the production of Saccharomyces cerevisiae yeast biomass in large quantities using the juice as the same carbon source. Determination of the best of five factors affects the production of dry biomass by baker’s yeast. The optimal value of the five factors affecting the process of biomass production by the baker’s sourdough was determined. The experimental design was performed using CCD (Central Composite Experimental Design), and the response surface methodology method was used to determine the best possible amount of production of yeast and has reached (41.44 g/L) after 12 hours of fermentation, under the following optimal conditions (temperature (30.11°С), pH (4.75), sugar concentration (158.36 g/L), the ratio of carbon to nitrogen (an essential nutrient for yeast growth) that is (11.9), and initial concentration of yeasts (2.5 g/L). Three kinematic models (Monod, Verhulst, and Tessier) were also selected for the purpose of studying the kinetic performance of S. cerevisiae yeast, and the best results were obtained based on the Verhulst model. The Leudeking Piret model has also been successfully used to estimate substrate during fermentation.