Application Of Membrane Separation Technology In Orange Juice Processing

Studies of membrane separation technology in concentrated orange juice processing were conducted in order to increase the value of orange through fine processing, improve the quality of the juice product, reduce the cost of production, promote the development of orange industry and apply the advanced membrane technology in the orange producing. The variation disciplinarian and technology parameter on the concentrated orange juice processing were revealed by the ultrafiltration(UF) separation and reverse osmosis(RO) experiments.1 Different pre-disposal methods have different effect on orange UF separation. Two kinds of pre-disposal methods, filtrating by 80 sieve pore and filtrating by 150 sieve pore then centrifugalization, were applied to dispose the orange juice, respectively. The results showed that membrane pollution was much severer and volume flow of solution through membrane was much smaller by 80 sieve pore filtrating than that by 150 sieve pore filtrating then centrifugalization. The main pollution materials of membrane were found to be lipoid, carotenoid and pectin, of which the severest contaminations are carotenoid.2 UF separation of orange juice had severe requirement to operating conditions. The effect of pressure, temperature and juice velocity of flow on volume flow of solution through membranes was studied. The volume flow of solution through membrane was increased as the temperature, pressure and juice velocity of flow arose. But the volume flow of solution decreased when the pressure reached 0.3 MPa. The results indicated that the optimal UF operating conditions were P=0.2Mpa, T=40癈, S=lm/s.3 Different scour had different effect on membrane cleaning. The best effect for membrane cleaning was obtained through 0.1%NaOH and 0.5%U10 consecutive cleaning on the conditions of P=2Mpa, T=40癈 and S=lm/s.4 The membrane made from PVDF of which the aperture is 50,000 is the appropriate membrane for the UF separation of orange juice. Interception ratio of pectin and carotenoid was analyzed and the results showed that the interception ratios were 97.86% and 98.32%, respectively. Therefore the main infectant was eliminated, which pollutes the RO membrane in concentration processing.5 Operating conditions of RO process and RO membrane cleaning were conducted. The results showed that RO-1 membrane was the right membrane for RO concentration of the orange juice. The feasible conditions were P=4.5Mpa, T=40癈 and S=lm/s. Both 0.1%NaOH and 0.5%U10 are wonderful scours for RO membrane cleaning. The polluted RO membrane could resume entirely cleaned by 0.1%NaOH and 0.5%U10 for 90 min and 60 min, respectively.6 Ingredients of mixed juice are analyzed after separation and concentration. Results indicated that composition and proportion of all the ingredients is equal to the concentration ratio between the fumet and concentrated juice. The concentration juice is rich in fragrance. The original color, luster and nutrition were also to be retained. The membrane separation technology is an excellent technique in orange juice processing.