Encapsulation of Phenolics in Kombucha Tea: Antioxidant Activity of End Products

Abstract

Kombucha tea is a beverage rich with phenolic compounds. In this study, encapsulation aims to minimize the degradation of phenolic compounds by using different coating materials namely maltodextrin and gum Arabic. Encapsulated Kombucha tea was obtained by freeze-drying process and the antioxidant activity was assessed by using DPPH and FRAP assays. Gum Arabic also demonstrated consistently higher TPC (254.75 mg GAE/g) and antioxidant activities (141.36 mg GAE/g) values compared to that of maltodextrin. The results of identified compounds showed the catechins of Kombucha tea were successfully encapsulated with the presence of sugar moieties in the chemical structure. The results revealed the presence of of catechins with glucose moiety viz; (−)-epigallocatechin 3-gallate, (−)-epicatechin pentaacetate, epicatechin 3-gallate and gallocatechin(4α→8)-epicatechin in encapsulated Kombucha tea. Kombucha tea exhibited similar trends of pre- and post-encapsulation antioxidant activity. Conclusively, this study presents important information to elucidate the potential actions of organic acids and the activities of Kombucha tea following fermentation and encapsulation process.