High Density Culture Process and Growth Kinetics of Flavor Yeast A10-2

Abstract

In order to realize the high-density culture and establish the predictive growth kinetics model of a self-isolated flavor yeast, the high-density culture process was studied of 4-ethyl-2-methoxyphenol producing yeast A10-2, which screened from soy sauce fermentation mash. The type of culture medium (nitrogen and carbon source) and concentration were studied and optimized. The growth kinetics and the substrate (total sugar) consumption models were established and verified. The results showed that (NH4) H2PO4 fed to make the concentration of culture medium 0.2 g/100 mL was the best inorganic source of nitrogen. To obtain the best cell growth rate, molasses as the only source of carbon, should be fed which controlled the concentration of total sugar in the culture medium to 0.4~0.6 g/100 mL. The growth of A10-2 yeast followed the S-shaped curve of a Logistic model, and the substrate (total sugar) consumption followed the Leudeking-Priet equation. The maximum obtained biomass specific growth rate μm was 0.4764 h−1, while the maximum biomass growth yield coefficient YG was 0.5879 g/g. The maintenance coefficient was 0.0127 g·L−1·h−1. The established models could better describe the growth and sugar consumption of yeast in the process of high-density culture, and have predictive significance