DEVELOPMENT AND STORAGE QUALITY EVALUATION OF PEACH AND STRAWBERRY STEVIA SWEETENED JUICE

Abstract

Background: Diabetes mellitus is a growing global health concern that contributes to serious complications including cardiovascular disease, obesity, and kidney dysfunction. With increasing awareness about the negative impacts of excessive sugar intake, there is a pressing demand for natural, non-nutritive sweeteners in functional food development. Stevia rebaudiana Bertoni, known for its high sweetness intensity and potential antidiabetic properties, is gaining attention as a suitable alternative to sugar in food and beverages.

Objective: This study aimed to evaluate the effect of stevia incorporation in peach and strawberry juices on their antioxidant potential, physicochemical properties, and sensory acceptability over a 30-day storage period.

Methods: Fresh peach and strawberry juices were prepared with varying concentrations of stevia (4%, 6%, and 8%) and compared against sucrose-based controls. Juices were bottled, pasteurized, and stored at 4±1°C. Evaluations of total phenolic content (TPC), DPPH radical scavenging activity, total acidity, total soluble solids (TSS), reducing sugars, and color values were conducted at 15-day intervals. Sensory analysis was carried out using a 9-point hedonic scale by a panel of 15 trained volunteers. Data were statistically analyzed using two-way ANOVA at a significance level of p<0.05.

Results: Stevia significantly enhanced antioxidant potential, with TPC and DPPH values decreasing from 153.09±19.20 to 136.60±19.33 mg GAE/100g and 40.03±3.50% to 27.79±3.35%, respectively, over storage. Total acidity increased from 0.33±0.10% to 0.83±0.03%, TSS ranged between 11.44±0.69 and 7.77±0.04 °Brix, and reducing sugars rose from 2.39±0.10% to 5.97±0.23%. Sensory attributes declined over time but remained within acceptable limits.

Conclusion: Stevia-sweetened fruit juices offer a promising alternative to sugar-based beverages, with better antioxidant retention and acceptable sensory quality, making them suitable for individuals with diabetes mellitus.