Effect of fermentation conditions on antioxidative, antimicrobial and techno-functional properties of Camellia sinensis leaves

Abstract

Introduction and Aim: Fermented food is an excellent source of nutrition as it contains promising bioactive compounds. Black tea is a fermented product and the most commonly used beverage. In the present study, the effects of various fermentation conditions and drying techniques on the proximate nutritional analysis, phytochemicals, tannin, antioxidative, and antimicrobial activity of Camellia sinensis leaves were examined. Materials and Methods: The FTIR analysis was performed to detect the presence of different functional groups. Using standard methods, total phenol, flavonoid, and tannin content were determined. The antioxidant activity was determined by using DPPH, ABTS, and FRAPS assays. Results: The results showed a decrease in protein content and an increase in ash, moisture, and crude fiber content, indicating that the samples’ nutritional profiles were improved after fermentation processing. The FTIR results showed the presence of hydroxy, carboxyl, amine, alkane, alkene, and alkyne bonding. The antioxidant activity of fermented samples was more than that of unfermented ones. Fermented samples had strong antimicrobial activity against Escherichia coli. An increase in TPC and TFC contributed to the rise in the antioxidant activity of the fermented sample. An increase in TSS suggested improvement in flavour and sweetness. Antimicrobial activity against Escherichia coli, demonstrated their potential as a natural antimicrobial agent. Conclusion: The enhanced antimicrobial activity of fermented tea leaves highlights the importance of the fermentation process in producing tea with improved microbial control and possible health benefits.