Effect of pre-treatment on aggregation, biochemical quality and membrane clarification of pomegranate juice

Pomegranate (Punica granatum L., Punicaceae) is the most popular tropical non-citrus fruits, mainly because of their attractive aroma, refreshing flavour and Brix/acid ratio. The research was carried out on the physicochemical analysis and membrane clarification of pomegranate juice after pretreatment. Pretreatment of pomegranate juice was performed using egg albumin with different concentrations and observed that 2 g/L concentration gave effective removal of colloidal substances of both juices. The biochemical analysis of pomegranate juice after pretreatment revealed the that of TSS, colour intensity, browning index, turbidity, titrable acidity, pH, viscosity, total antioxidant activity, total phenolic content, total anthocyanin content, reducing sugars, non-reducing sugars, total sugars and colour as 12.985%, 7.695, 4.726, 0.751%, 0.784%, 4.753, 2.326 cP, 37.221 mg/g, 57.225 (mg of GAE/g of dry material), 12.461 mg/100mL, 5.754%, 2.671%, 8.425% and 3.842, respectively. There were significant differences among all the treatments of pomegranate juice. Permeate flux generally declined with time for both microfiltration (MF) and ultrafiltration (UF). However, increase in permeate flux was achieved with increase in TMPs and feed flow rates. The permeate flux was high during MF of pomegranate juice than UF. The decrease in pore size and MWCO also decreased the permeate flux. In MF and UF of pomegranate juice, the initial fluxes were high but gradually decreased.