Physiological and fermentative performance of non- yeasts isolated from kombucha for beer production.

This study aimed to isolate, identify, and characterize kombucha yeasts for beer production. Nineteen yeasts were isolated, and the species sp., , and were identified. The strains L652, L472, L231, L431, and L131, and L331 present desired physiological properties for beer production, including tolerance to 6% ethanol, 100 mg/L of iso-α-acid and flocculation capacity. It was selected for wort fermentation at 10 °C and 20 °C. Beers with different chemical characteristics were produced when evaluated at 10 °C and 20 °C for all strains. Minor carbohydrate residuals and higher ethanol concentrations were observed in the beers fermented at 20 °C. All non- yeasts evaluated produced alcohol-free beers (<0.5%) at 10 °C. At 20 °C, only the yeast L431 produced non-alcoholic beer (0.24%). The yeasts L131, L231, and L472 and L652 produced beers with reduced alcoholic content (0.6-1.4%), and the strains L331 produced alcoholic beer (2.45%). Relating acetic acid, the strains L431 and L472 presented higher concentrations (0.226 g/L and 0.264 g/L, respectively) at 10 °C, while L331 showed the highest concentration (0.936 g/L) at 20 °C, demonstrating the potential to produce sour beers. These results indicate that evaluating the yeast strain according to the beer style is crucial.