Changes in the content of total polyphenols and the antioxidant activity of different beverages obtained by Kombucha ‘tea fungus’

Abstract

Kombucha ‘tea fungus’ is a traditional refreshing drink obtained by fermentation of black tea with sugar as well as astrong symbiosis of acetic bacteria and yeasts. Kombucha tea has several health benefits such as antihyperglycemic,antilipidemic, antimicrobial, hepatoprotective, hypocholesterolemic and anticancer effects due to their antioxidantactivity. In this study, six kombucha beverages were prepared by placing Kombucha ‘tea fungus’ in green, blackand Echinacea teas, as well as goat, cow and soy’s milk. The fermentation process was monitored by pH, total sugaramount, and titratable activity, as well as their antioxidant activities and total phenolic contents, were analyzed priorto the fermentation process and at the end of fermentation. The results showed that tea-based beverages were fermented for nine days and milk-based beverages were for 6 hours. Their sugar contents were significantly decreased(p < 0.05) as depending on their sugar contents. All fermented beverages displayed a statistically significant decrease(p < 0.05) in the DPPH and ABTS radical scavenging activity at the end of fermentation, while FRAP assays weredisplayed a statistically significant increase (p < 0.05). Further studies are necessary to the research of nutrients of teaand milk-based beverages on human organs the throughout fermentation.