Development of a Prebiotic Oligosaccharide Rich Functional Beverage from Sweet Sorghum Stalk Biomass

Abstract

Sweet sorghum with sugar-rich stalks is considered a potential bioenergy crop. In this study, the sucrose in stalk juice was transformed into oligosaccharides by employing microbial and enzymatic methods. The maximum oligosaccharide yield of 10–14 g L−1 was obtained from 20 g L−1 sucrose in the sweet sorghum juice, representing conversion of about 82%–87% sucrose. The caloric value of the modified sweet sorghum juice was reduced by more than 50%. The probiotic bacteria exhibited a noteworthy growth profile in the modified sweet sorghum juice enriched with the non-digestible oligosaccharides. The antioxidative properties of the sweet sorghum stalk juice were not altered in the bioprocessed juice. The modified juice did not show any significant change in sensory properties after sucrose to oligosaccharide transformation. Furthermore, the oligosaccharides in the juice exhibited tolerance to heat exposure and, therefore, is feasible for food processing applications. The results suggested sweet sorghum as low-cost biomass for the development of plant-based functional products.