Physicochemical and Sensory Evaluation of Spreads Derived from Fruit Processing By-Products

Apple, tomato, and grape pomaces, as well as an apple-grape (1:1) mixed pomace, were employed in the formulation of fruit-based spreads to valorize these underutilized by-products. The influence of pectin addition on the physicochemical and sensory properties of the spreads was also examined. All spread preparations carried the 'high fiber' nutrition claim. The apple pomace spread demonstrated the highest total and soluble dietary fiber contents (14.13 and 4.28%, respectively). Colorimetry showed higher L* and a* values for the tomato pomace spreads. Rheometry of the spreads revealed pseudoplastic flow and weak gel-like behavior (G' > G″); the tomato and grape pomace spreads with pectin exhibited the highest η*, G', and G″ values. A texture analysis (spreadability test) indicated that pectin addition affected only the mixed pomace spread, resulting in the least spreadable product. Regarding bioactive compounds, the apple pomace had the highest total phenolic content, and the grape pomace exhibited the highest antioxidant activity, both of which were also reflected in their corresponding spreads. A principal component analysis indicated a strong correlation among flavor, mouthfeel, and moisture content, which were negatively correlated with color intensity and spreadability. The apple pomace spread with added pectin was the most widely preferred by consumers due to its appealing mouthfeel, spreadability and flavor.