Functional Beverages from Blends of Ficus Deltoidea Leaves and Brown Rice Powders: Physico-Phytochemical Properties, Antioxidant Activities, Sensory Evaluation and Acute Toxicity Study

Background: Ficus deltoidea (Ficus: Moraceae) has great potential as a functional food. Administration of F. deltoidea has been reported to reduce hyperglycemia, oxidative stress and increase insulin secretion in diabetic rats and humans. However, the poor bioavailability and intestinal absorption of F. deltoidea impede its therapeutic effectiveness at a lower dosage, thus integrating F. deltoidea into brown rice will provide additional advantages. This study aimed to examine the phyto-physicochemical profile, antioxidant properties, consumer acceptance, and safety of beverages formulated from fine powder mixtures of F. deltoidea leaves and brown rice. Methods: The new beverage formulations were prepared by mixing the fine powders of F. deltoidea leaves with brown rice at ratios of 1:6 and 1:13, respectively. Physicochemical, phytochemical, and antioxidant analyses were performed to characterize the prepared beverages. Consumer acceptance was assessed utilising a 9-point hedonic scale and an acute toxicity study was employed to determine the safety of F. deltoidea-added formulations. Results: F. deltoidea decreased the pH and increased the moisture content, ash, and viscosity of a brown rice beverage. The total phenolic, flavonoid, and tannin content as well as antioxidant activities increased significantly in both F. deltoidea-added formulations. The oral LD₅₀ of the F. deltoidea-added formulation was higher than 2000 mg/kg body weight. Conclusions: These results suggest that adding F. deltoidea leaves to brown rice beverages is safe to consume and improves the phyto-physicochemical profile, antioxidant activities, and consumers’ acceptance of the formulation.