PERMEATION BEHAVIOR OF BUFFALO MILK CHEDDAR CHEESE WHEY DURING ULTRAFILTRATION

The permeation behaviour of buffalo-milk Cheddar cheese whey during ul trafiltration was studied. Buffalo-milk Cheddar cheese whey was adjust ed to various pH levels ranging from 3.0 to 7.2 and ultrafiltration wa s carried out at 50-degrees-C to a level of 95% volume reduction by ma intaining 1.75 and 0.50 bar inlet and outlet pressures, respectively. It was observed that the retentate had a minimum ash content of 3.17% on a dry matter basis at pH 3.0 as against 6.23% when ultrafiltered at pH 7.2. As the pH was decreased from 7.2 to 3.0, the ash content of t he retentate was drastically reduced. The calcium and phosphorus conte nt of the retentate also varied significantly with change in pH, being minimal at pH 3.0 and increasing significantly with increase in pH of the whey. The yield of protein and lactose in the final retentate als o varied with the pH of the whey. The permeate had a total solids cont ent ranging from 5.65 to 5.78%. The maximal ash content of 0.59% was o bserved in the permeate when ultrafiltered at pH 3.0. As the whey pH i ncreased, the ash content in the permeate decreased significantly. The total protein content of the permeate ranged from 0.18 to 0.23 %. Mos t of the protein was observed to be non-protein nitrogen. Polyacrylami de gel electrophoresis showed the presence of alpha-lactalbumin and tr aces of beta-lactoglobulin in the permeate. The lactose content of the permeate ranged from 4.98 to 5.02%. The results indicate that the fin al composition of whey protein concentrate can be altered by monitorin g the volume reduction as well as by adjusting the whey pH before ultr afiltration.