Abstract

Clarification of Pomegranate Juice at Industrial Scale

Manuel Valero, Salud Vegara, Nuria Martí and Domingo Saura

The effects of conventional and membrane clarification processes on some physicochemical properties of pomegranate juice such as color, turbidity, Total Soluble Solids (TSS), Total Phenolic Content (TPC), antioxidant activity and bioactive compounds (anthocyanins, ellagitannins and ellagid acid) were evaluated. Changes in color parameters such as absorbance at 520 nm (A520, red color), Total Color Density (TCD) and Browning Index (BI), as well as TPC were negatively influenced by bentonite or albumin concentration in batch processes. However, both microfiltration (MF) and ultrafiltration (UF) processes at the applied conditions did not cause any significant differences on the levels of A520, BI, TPC, and other parameters determined as part of the evaluation study. Moreover, the permeate flux in MF were higher than in UF, which is preferable for commercial application of tangential filtration technology in pomegranate juice industry. MF-clarified juice had physicochemical and nutritional properties similar to those of fresh juice.