A Novel and Efficient Concentration of Pomegranate Juice with Enhanced Antioxidant Activity

In the present study we investigated the performance of a panel of 13 solid sorbents comprising layered double hydroxides, zirconium phosphate-based materials, and phyllosilicates as heterogeneous supports for the concentration of pomegranate (Punica granatum L.) juice. Mg-containing clays exhibited an almost complete bleaching capacityof pomegranate juice and more interestingly provided blends with an increased antioxidant capacity (around 1.5-fold) respect to the parent juice when assayed for the Trolox equivalent antioxidant capacity (TEAC) coupled to ABTS decolorization test. Such an activity remained practically unaltered after 4 days during which the pomegranate concentrated preparations remained supported on clays. The approach investigated herein and used for the concentration of pomegranate juice and the discovery of the preservation for long periods of the antioxidant activities of pomegranate extracts when supported on solid sorbents have been reported herein for the first time in the literature to the best of our knowledge.