Is It Possible to Brew Non-Alcoholic Kombucha? Brazilian Scenario after Restrictive Legislation

Abstract

Kombucha is a traditional fermented beverage produced via the fermentation of a sweetened Camellia sinensis infusion added to a symbiotic culture of bacteria and yeast (SCOBY). During fermentation, a high level of ethanol can be produced as a yeast metabolite that can reach values above the legal limits for non-alcoholic beverages. In 2021, Brazil made the world’s first kombucha-specific legislation to label beverages containing up to 0.50% ABV (alcohol by volume) as non-alcoholic. Headspace gas chromatography was used to quantify ethanol in 12 kombucha samples from different brands 12 months before and after the legislation was implemented. Before the legislation was implemented, 92% of the samples showed ethanol concentrations above 0.50% ABV, ranging from 0.47% to 3.56% ABV. One year later, an analysis of the same 12 kombucha brands showed that 67% of the samples were non-compliant with the new legislation, ranging from 0.10% to 2.40% ABV. The formation of ethanol during kombucha fermentation is a multivariate problem. Inoculum usually differs between sources, and the types and amounts of sugar and fruits, and the tea infusion percentage can also impact the final product. These parameters vary among producers. Some efforts to help kombucha producers achieve a more controlled and consistent production process are needed to ensure that commercially available kombuchas are properly non-alcoholic beverages and safe to consume.