Kinetics of saccharose fermentation by kombucha

Abstract

© 2014, Serbian Chemical Society. All rights reserved. The kinetics of saccharose fermentation by Kombucha is not yet well defined due to lack of knowledge of reaction mechanisms taking place during this process. In this study, the kinetics of saccharose fermentation by Kombucha was analysed using the suggested empirical model. The data were obtained on 1.5 g L-1 of black tea, with 66.47 g L-1 of saccharose and using 10 or 15% (V/V) of Kombucha. The total number of viable cells was as follows: approximately 5.105 of yeast cells per mL of the inoculum and approximately 2x106 of bacteria cells per mL of the inoculum. The samples were analysed after 0, 3, 4, 5, 6, 7 and 10 days. Their pH values and contents of saccharose, glucose, fructose, total acids and ethanol were determined. A saccharose concentration model was defined as a sigmoidal function at 22 and 30 °C, and with 10 and 15% (V/V) of inoculum quantity. The determination coefficients of the functions were very high (R2 > 0.99). Reaction rates were calculated as first derivatives of Boltzmann’s functions. No simple correlation between the rate of reaction and independent variables (temperature and inoculum concentration) was found. Analysis of the empirical model indicated that saccharose fermentation by Kombucha occurred according to very complex kinetics.