Filtration of Milk Fat Globule Membrane Fragments from Acid Buttermilk Cheese Whey

The SDS-PAGE of butterserum whey permeates, obtained with different membranes. Lane 1: 30-kDa polyethersulphone (PES); lane 2: 0.1-μm PES; lane 3: 0.15-μm cellulose acetate (CA); lane 4: 0.2-μm CA; lane 5: 0.2-μm PES; lane 6: 0.45-μm CA; lane 7: 0.15 CA + thermocalcic aggregation (TA); lane 8: 0.45 CA + TA; lane 9: acid buttermilk cheese whey; lane 10: milk fat globule membrane (MFGM) standard; lane 11: molecular weight marker. Observed MFGM proteins are adipophilin (ADPH), cluster of differentiation 36 (CD36), periodic acid Schiff 6/7 (PAS 6/7), proteose peptone 3 fraction 1 and 2 (PP3), and xanthin oxidase/dehydrogenase (XO). Observed whey proteins are BSA, immunoglobulin heavy chain (IGH), α-LA, and β-LG genetic variant A and B. Butyrophilin (BTN), one of the main MFGM proteins, was not observed.

Permeate flux during the filtration of acid buttermilk cheese whey (pH 4.46), using different membranes: □ 0.45-μm cellulose acetate (CA), ■ 0.2-μm CA, ▽ 0.15-μm CA, ▾ 0.2-μm polyethersulfone (PES), ♦ 0.15μm-CA + thermocalcic aggregation treatment, ○ 0.1-μm PES, ♢ 0.45-μm CA + thermocalcic aggregation treatment, ● 30-kDa PES. Temperature was kept at 40°C, the transmembrane pressure at 0.1MPa and the feed velocity over the membrane at 2.14m/s.

Polar lipid retention coefficient as a function of temperature and pH upon filtration of acid buttermilk cheese whey with a 0.15-μm cellulose acetate membrane.

Protein retention coefficient as a function of temperature and pH upon filtration of acid buttermilk cheese whey with a 0.15-μm cellulose acetate membrane.

Lipid retention coefficient as a function of temperature and pH upon filtration of acid buttermilk cheese whey with a 0.15-μm cellulose acetate membrane.

Fouling coefficient as a function of pH upon filtration of acid buttermilk cheese whey with a 0.15-μm cellulose acetate membrane. The temperature term was found insignificant.

Permeate flux during the filtration of acid buttermilk cheese whey using a 0.15-μm cellulose acetate (CA) membrane at different temperature (°C)-pH combinations. ▽ (50, 7.5); ■ (32.5, 5.75); ▾ (50, 4); ● (15, 7.5); ○ (15, 4). The transmembrane pressure was kept at 0.1MPa and the feed velocity over the membrane at 2.14m/s.

The SDS-PAGE of butterserum whey retentates and permeates after diafiltration at 50°C and at a pH of 7.5. Lane 1: molecular weight marker; lane 2 to 4: diafiltration retentate step 1 to 3; lane 5 to 7: diafiltration permeate step 1 to 3; and lane 8: buttermilk whey. The vertical streaking in lane 4 was caused by the presence of polar lipids. XO=xanthin oxidase/dehydrogenase; CD36=cluster of differentiation 36; IGH=immunoglobulin heavy chain; ADPH=adipophilin; PAS 6/7=periodic acid Schiff 6/7; PP3=proteose peptone 3 fraction 1 and 2.