Addition of Orange By-Products (Dry Peel) in Orange Jam: Evaluation of Physicochemical Characteristics, Bioactive Compounds and Antioxidant Activity

The aim of the present study was to assess the effect of treatment and storage period on the nutritional quality of enriched orange jam during storage for 90 days at 15 and 30 °C. The jam was produced by traditional technique using traditional pectin (TP) and with addition of orange peel (OP). All samples were evaluated for pH, total soluble solids, acidity, total phenolic content, total carotenoid content and antioxidant activity (DPPH and ABTS assay). The mean values at T0 of total soluble solids, titratable acidity and pH of TP jam samples were 63.03 °Brix, 0.60% and 3.51, respectively. While the values for OP jam samples were 65.11 °Brix, 0.61% and 3.68, respectively. The polyphenols ranged from 83.44 to 126.22 mg/100 g for control samples and from 125.12 to 171.02 mg/100 g for enriched jam. As regards temperature storage, the enriched jam stored at 15 °C maintained better analytical parameters than the samples stored at 30 °C. The results obtained from the experimentation show that use of orange peels in orange jam preserved the functional characteristics during storage