The Effect of Aqueous Extract of Rosa canina on Antioxidant Activity, Sensory Evaluation, and Physicochemical Properties of Yogurt.

In recent years, there has been growing scientific interest in developing functional foods with medicinal properties. In the context of dairy product innovation, the aqueous extract of Rosa canina (R. canina) has emerged as a promising bioactive compound. This study aimed to evaluate the impact of incorporating R. canina aqueous extract at four concentrations (0%, 0.5%, 1%, and 1.5%) on the antioxidant activity, sensory evaluations, and physicochemical properties of yogurt. Antioxidant activity was evaluated using DPPH and ABTS assays, phenolic compounds were quantified with the Folin-Ciocalteu method, physicochemical properties (pH, acidity, syneresis) were measured by standard procedures, and sensory evaluation was performed using a 5-point hedonic scale. The findings revealed that the addition of R. canina extracts significantly enhanced the acidity of the yogurt samples (p < 0.05). This value exhibited a pronounced increase from 0.62 to 0.90 g/L in the 1.5% samples over the storage period. A significant reduction in pH was observed across all treatment groups supplemented with R. canina extract throughout the storage duration (p < 0.05). Furthermore, the incorporation of the extract led to a marked increase in phenolic compounds, with the yogurt containing 1.5% extract reaching a phenolic content of 857.67 (mg GAE eq.)/kg. The antioxidant activity of the yogurt was also significantly enhanced by the addition of the extract compared to the control group (p < 0.05), which was increased to 2570.67 (mg BHT eq.)/kg in the 1.5% samples over a 3-week storage period. However, the syneresis of the yogurt samples increased with higher concentrations of the extract across all storage intervals. The sensory evaluation demonstrated that the inclusion of R. canina extracts improved the sensory scores for the appearance, taste, texture, and overall acceptability of the yogurt samples compared to the control. These results suggest that R. canina aqueous extract can serve as a functional ingredient in yogurt production, enhancing its bioactive properties and sensory appeal while influencing its physicochemical characteristics.