Functional potential of a new plant-based fermented beverage: Benefits through non-conventional probiotic yeasts and antioxidant properties

Functional foods represent one of the fastest-growing, newer food category, and plant sources with functional properties are increasingly used as analogues of fermented milk-based derivatives. In this study, blended wortrooibos beverages fermented with probiotic yeasts are proposed for the first time. Benefits of functional, nonconventional Lachancea thermotolerans (Lt101), Kazachstania unispora (Kum3-B3), Meyerozyma guilliermondii (Mg112), Meyerozyma caribbica (Mc58) and Debaryomyces hansenii (Dh36) yeast strains and the content of bioactive metabolites were evaluated. Viability tests on the probiotic yeasts confirmed previous results obtained in other matrices. The functional footprint of probiotic yeasts Lt101, Mg112 and Dh36 was confirmed by a balanced nutritional profile of the final drinks, also supported by aromatic and sensory analyses. In vitro estimated glycaemic index ranged between 77 % and 87 % without any influence on glycaemic response. Strains Dh36, Mc58, Kum3-B3 and Mg112 showed high antioxidant capacity and high total phenolic content, supporting the health promoting effect of the beverages.