Integrated Membrane Process for the Production of Nagpur Mandarin (Citrus reticulata Blanco) Juice Concentrate: Impact on Nutritional Content and Antioxidant Activity

Juice concentrates occupy the processed food market minimizing storage cost and resistant to decay. The present study conducted to evaluate the ultrafiltration, reverse osmosis and osmotic distillation (UF-RO-OD) process on a laboratory pilot unit for production of Citrus reticulata Blanco fruit juice concentrate. The membrane modules performance was tested by its productivity and quality of concentrate in terms of ascorbic acid and antioxidant activity. The method was carried by batch concentration mode. During process, UF clarified the juice feed of 8.9°Brix and RO process concentrates upto 21.0°Brix. Finally, OD process concentrates the RO retentate and yielded a concentrate of 60°Brix giving evaporation flux (0.3kg/m²h). Calcium chloride dihydrate (56.9w/w%) was used as stripping solution. The antioxidant activity 9.69 mmol L⁻¹ Trolox and TSS 60.4°Brix of concentrate were obtained. On the basis of results obtained, integrated membrane process can be suggested for producing juice concentrate sustaining the characteristics of the fresh fruit juice.