Production and Characterization of Kombucha Tea from Different Sources of Tea and Its Kinetic Modeling

This study aimed to investigate the fermentation performance, sugar consumption, pH changes, total phenolic compounds, and antioxidant activity produced using different tea extracts and sugar concentrations and the kinetic characteristics of Kombucha fermentation. Three independent sugar concentrations (10 g/L, 40 g/L, and 70 g/L) were used in the fermentation process. The results showed that the Kombucha culture consumed all sugar in the fermentation medium when the sugar concentration was below a certain threshold, but when the sugar concentration was high, not all substrate was consumed. Sugar consumption values ranged from 48.39 to 55.40 g/L and affected biomass formation, with higher sugar consumption resulting in increased biomass production. The pH decreased during fermentation due to the production of organic acids and microbial by-products, while total acidity increased. Total phenolic compounds increased during fermentation, with the highest concentrations observed in herbal Kombucha teas. Antioxidant activity varied, with some samples showing a decrease in DPPH scavenging ability. Kinetic characterization revealed the relationship between substrate depletion, sugar consumption, total acidity, and phenolic compound production. The results showed that sugar concentration influenced the fermentation kinetics and end-product characteristics of Kombucha tea. Overall, this study provides valuable insights into the fermentation process of Kombucha tea and its impact on various parameters, contributing to the understanding of the factors affecting its quality and health benefits.