Determination of the efficiency of removal of whey protein from sweet whey with ceramic microfiltration membranes
Brandon Carter, Larissa DiMarzo, Joice Pranata, D.M. Barbano, M.A. Drake
Abstract
Our research objective was to measure percent removal of whey protein from separated sweet whey using 0.1-m uniform transmembrane pressure ceramic microfiltration (MF) membranes in a sequential batch 3-stage, 3 process at 50C. Cheddar cheese whey was centrifugally separated to remove fat at 72C and pasteurized (72C for 15 s), cooled to 4C, and held overnight. Separated whey (375 kg) was heated to 50C with a plate heat exchanger and microfiltered using a pilot-scale ceramic 0.1-m uniform transmembrane pressure MF system in bleed-and-feed mode at 50C in a sequential batch 3-stage (2 diafiltration stages) process to produce a 3 MF retentate and MF permeate. Feed, retentate, and permeate samples were analyzed for total nitrogen, noncasein nitrogen, and nonprotein nitrogen using the Kjeldahl method. Sodium dodecyl sulfate-PAGE analysis was also performed on the whey feeds, retentates, and permeates from each stage. A flux of 54 kg/m 2 per hour was achieved with 0.1-m ceramic uniform transmembrane pressure microfiltration membranes at 50C. About 85% of the total nitrogen in the whey feed passed though the membrane into the permeate. No passage of lactoferrin from the sweet whey feed of the MF into the MF permeate was detected. There was some passage of IgG, bovine serum albumen, glycomacropeptide, and casein proteolysis products into the permeate. -Lactoglobulin was in higher concentration in the retentate than the permeate, indicating that it was partially blocked from passage through the ceramic MF membrane.