Effect of stevia and pectin supplementation on physicochemical properties, preservation and in‐vivo hypoglycemic potential of orange nectar

Abstract

This work aims to optimize a new formulation of orange nectar sweetened with Stevia and enriched with Pectin using full factorial design with two factors, two levels, and one central point. Factors were the concentration in stevia and pectin. Physicochemical characterization and stability study were carried-out at 4 and 25°C where pH, Brix°, total titratable acidity, turbidity, sedimentation, and redispersibility are controlled for 1 month. The evaluation of antioxidant activity degradation during 3 months and organoleptic test were required for the selection of optimal formulation. The hypoglycemic effect of the optimal nectar was evaluated in rats targeting the postprandial blood glucose levels kinetics. After optimization, the formulation F1 (with 0.03% stevia and 0.05% pectin) was found to be the most stable and favorable. Its half-life times were, respectively, 147.67 days at 4°C (R2 = .996) and 74.66 days at 25°C (R2 =.997). Its organoleptic score was 9.67 (R2 = .994). The in-vivo hypoglycemic study has been confirmed, the effect of this supplementation has permitted the regulation of post-prandial glycemic levels. Thus, this formulation deserves to be recommended for diabetic subjects. Practical applications The addition of stevia (0.03%) and pectin (0.05%) improved the physico-chemical stability of natural orange nectar. Referring to the antioxidant activity degradation; half-life time was 147.67 days at 4°C and 74.66 days at 25°C. The consumption of this orange nectar by diabetic patients allows the normalization of their postprandial blood glucose levels.