Assessment of the antioxidant properties during storage of a dessert made from grape, cherry, and berries

A 1-y storage trial was designed involving different temperatures (8, 21, and 30 C) to assess the antioxidant properties of a dessert formulated with concentrated juices of grape, blackberry, blackcurrant, raspberry, and cherry. The total antioxidant activity (TAA) of the dessert was measured as the scavenging capacity of the 2,2'-azino-di-[3-ethylbenzothiazoline-6-sulphonate] radical cation (ABTS) and as its iron-reducing ability (FRAP). Color was spectrophotometrically measured, and vitamin C and phenolics were analyzed by HPLC. The color parameters and the concentrations of different antioxidant compounds were affected by storage conditions, especially in samples stored at 30 C, although the TAA remained practically invariable during storage.