Kombucha is a fermented tea beverage. It is made by adding a symbiotic culture of bacteria and yeast (SCOBY) to a solution of tea and sugar. During the course of the fermentation process, the cultures metabolize the sugar and tea components to render a naturally carbonated beverage, with a slightly sweet-tart flavor, full of healthy components like B vitamins, organic acids, antioxidants, and trace amounts of alcohol.
During the first part of the fermentation process the yeasts – mainly Brettanomyces along with Saccharomyces and Zygosaccharomyces – consumes the sugars and leaves CO2 and Alcohol as metabolites. The bacteria in the SCOBY – Acetobacter, Lactobacillus and Gluconacetobacter are the main species – then consumes the alcohol and leaves a range of organic acids as metabolites.