Kombucha | TTB: Alcohol and Tobacco Tax and Trade Bureau The term "kombucha" generally refers to a fermented beverage produced from a mixture of steeped tea and sugar, combined with a culture of yeast strains and bacteria Some kombucha products also have fruit juice or other flavors added during production The combination of sugar and yeast triggers fermentation, which may produce a kombucha with an alcohol content of 0 5% or more alcohol by volume