Palatability and chemical safety of apple juice fortified with pomegranate peel extract

Pomegranate peel extract (PPE), a by-product of the pomegranate juice industry with potential health effects, was explored for use to fortify reconstituted apple juice in the concentration range 0.5 to 2.0% (w/w). Radical scavenging and antioxidative capacities of the fortified apple juices were evaluated using (i) electron spin resonance (ESR) to quantify their ability to scavenge the stable radical Fremy's salt and (ii) the Trolox equivalent antioxidant capacity (TEAC) assay and compared to apple juice without fortification as control. The highest antioxidative capacity was found in the apple juice fortified with the highest percentage of pomegranate peel extract, while the optimal sensory quality was found by addition of 0.5 g PPE per 100 mL. The Artemia salina assay was used as a fast screening method for evaluating overall toxicity, and showed little toxicity with up to 1.0 g per 100 mL addition of PPE, but increasing toxicity at higher concentrations. Accordingly, it is important to balance addition of PPE, when used for enrichment of apple juice in order to obtain a healthier product, without compromising the sensorial quality or toxicological safety of the apple juice. Concentrations between 0.5 and 1.0 g PPE per 100 mL seem to be acceptable.