Concentration of blackcurrant juice by reverse osmosis

The aim of this study was to examine the applicability of reverse osmosis (RO) for the concentration of blackcurrant juice by AFC-80 polyamide tubular membrane that has a salt rejection greater than 80%. The fresh juice had a total soluble solids content of about 16.5°Brix. The effect of centrifugation followed by depectinization with two commercially available pectinase enzyme preparations (Panzym Super E and Trenolin Rot DF) on the permeate flux has been evaluated. For the description of the concentration process, the resistance-in-series model has been used. It was concluded that the applied RO membrane is suitable for concentration of blackcurrant juice up to 28.6°Brix, which was achieved with the juice that had been treated with Panzym Super E. The total resistances were calculated and compared, taking into account membrane fouling and polarization layer resistance.