Screening, antioxidant and probiotic properties of a fermented beverage based on buttermilk, Lactobacillus gasseri LG08 and curcumin

Abstract This Research Paper addresses the hypothesis that the use of a probiotic and the antioxidant and anti-inflammatory action of curcumin will improve the use of buttermilk, which is a by-product of the dairy industry that is still little used, despite its nutritional and technological properties. The production of beverages using buttermilk as a basis will contribute to the development of foods that support sustainability, reduce waste and have high nutritional quality. The aim of this research is to develop a functional dairy beverage with high antioxidant potential, combining probiotic ( Lactobacillus gasseri LG08) and bioactive compounds through buttermilk fermentation and curcumin addition. To this end, four formulations were prepared: (1) pasteurized buttermilk (BM), (2) pasteurized buttermilk + curcumin (CUR), (3) pasteurized fermented ( L. gasseri LG08) buttermilk (FBM) and (4) pasteurized fermented ( L. gasseri LG08) buttermilk + curcumin (FCUR). We evaluated proximal composition and physicochemical properties (pH, titratable acidity, soluble solids, colour and water-holding capacity), microbiological and antioxidant capacity over 28 days and in vitro cytotoxicity. For comparison among experimental formulations, ANOVA followed by the Tukey test was used for parametric variables, and for non-parametric variables, Kruskal–Wallis followed by Dunn’s, using BM as the control. For comparison over storage time, ANOVA was performed. The analyses show the effect of fermentation on beverages with added Lactobacillus , with a reduction in pH and an increase in acidity. The use of curcumin resulted in changes not only in colour but also in the antioxidant content of the beverages. At 100 μg/ml, all formulations were non-cytotoxic. Furthermore, in the evaluation of cell viability, the FCUR beverage at the highest concentration improved viability after stress with hydrogen peroxide. Fermentation using the lactose content in buttermilk was effective. Curcumin enhanced visual appeal and bioactivity without cytotoxic effects. Utilizing underused by-products reduces waste and supports sustainability.