The chemistry and sensory characteristics of new herbal tea-based kombuchas

Abstract

Kombucha is a black tea-based, non-alcoholic beverage fermented by yeast and bacteria are known for its refreshing scent and taste and presents biological characteristics, namely antioxidant, antimicrobial and anti-inflammatory activity. The present study compared traditional kombucha prepared with black tea and green tea to kombuchas produced with several alternative substrates, including white tea, chrysanthemum, honeysuckle, and mint infusions. Throughout the fermentation process, liquid and gas chromatography analyzed sugars, ethanol, organic acids, and volatile compounds. Sugar consumption was substrate-dependent, with mint kombucha having the highest amount of residual sugar and honeysuckle having the lowest. Forty-six volatile organic compounds were detected, including alcohols, esters, acids, aldehydes, ketones, and other compounds. Twenty-two compounds were produced during the fermentation and identified in all kombuchas; some of these compounds represented fruity and floral aromas. Another 24 compounds were substrate specific. Notably, the herb-based kombuchas (chrysanthemum, honeysuckle, and mint) contained several compounds absent in the tea-based kombuchas and are associated with minty, cooling, and refreshing aromas. Mint and green tea kombucha attained the highest and lowest overall sensorial acceptance ratings, respectively. This study demonstrated herbal substrates' suitability to prepare kombucha gastronomically with volatile compound and flavor profiles distinct from tea-based kombuchas.