Fermentation with Tea Residues Enhances Antioxidant Activities and Polyphenol Contents in Kombucha Beverages

Abstract

Kombucha is a popular beverage with various bioactivities (such as antioxidant activity), which can be attributed to its abundant bioactive compounds, especially polyphenols. Kombucha is conventionally prepared by fermentation of a sugared black tea infusion without tea residue. In this study, the effects of black tea residue and green tea residue on kombucha were studied, and its antioxidant activities, total phenolic contents, as well as concentrations of polyphenols at different fermentation stages were evaluated using ferric-reducing antioxidant power, Trolox equivalent antioxidant capacity, Folin-Ciocalteu method and high-performance liquid chromatography with a photodiode array detector. The results showed that fermentation with tea residue could markedly increase antioxidant activities (maximum 3.25 times) as well as polyphenolic concentrations (5.68 times) of kombucha. In addition, green tea residue showed a stronger effect than black tea residue. Overall, it is interesting to find that fermentation with tea residues could be a better strategy to produce polyphenol-rich kombucha beverages.

Antioxidant Capacities and Polyphenol Contents of Kombucha Beverages Based on Vine Tea and Sweet Tea

“…Numerous studies have shown that alternative raw materials could allow the kombucha beverages significant antioxidant activities and increase the amounts of bioactive compounds [ 10 , 23 , 24 ]. Moreover, fermentation with tea residues was found to increase antioxidant capacities as well as polyphenol contents of kombucha [ 12 ]. Therefore, in this study, we adopted vine tea and sweet tea to develop new kombucha beverages, and compared the effects of kombucha beverages fermentation with or without tea residues.…”

“…The concentrations of bioactive components in kombucha beverages were measured by HPLC-PDA based on previous studies [ 12 , 17 ]. Separation was performed using an Agilent Zorbax Eclipse XDB-C18 column (250 mm × 4.6 mm, 5 µm) (Santa Clara, CA, USA).…”

“…These kombucha beverages from non- Camellia sinensis teas could have significant biological activities and health benefits because they could contain various bioactive components, such as cinnamaldehyde, eugenol, chlorogenic acid, caffeic acid, 6-gingerol, 6-shogaol, quercetin and vanillic acid [ 10 , 11 ]. Furthermore, a recent study found that the antioxidant capacities and polyphenol contents of kombucha beverages could be significantly increased with tea residue fermentation [ 12 ].…”

“…The antioxidant activities were determined by ferric-reducing antioxidant power (FRAP) assay and Trolox equivalent antioxidant capacity (TEAC) assay, and the total phenolic contents (TPC) was determined by the Folin-Ciocalteu method. In addition, the concentrations of several bioactive components in two kombucha beverages were measured using high-performance liquid chromatography with photodiode array detector (HPLC-PDA) [ 12 , 17 ], including gallic acid, dihydromyricetin, myricetin, gallic acid, chlorogenic acid, catechin, rutin and ellagic acid. These kombucha beverages were studied for the first time, and found to possess strong high antioxidant activities (especially vine tea kombucha), which could be used as functional foods to prevent several diseases with related of oxidative stress.…”

Exploring the Mangrove Fruit: From the Phytochemicals to Functional Food Development and the Current Progress in the Middle East

“…The bacteria are from the genera Acetobacter and Gluconobacter , while the yeast is Mycoderma , Mycotorula , Pichia , Kloeckera , Brettanomyces , Torulospora , Candida , Schizosaccharomyces , Saccharomycodes , Zygosaccharomyces , and Saccharomyces [ 172 ]. The beverage has a sour and sweet taste based on the type of starter, and the flavor comes from tannin transformation [ 173 ]. Kombucha herbal tea is famous for its antioxidant and antimicrobial activities [ 174 ].…”