High-Pressure–Induced Interactions Between Milk Fat Globule Membrane Proteins and Skim Milk Proteins in Whole Milk

• Published in: Journal of dairy science Vol. 87; no. 12; pp. 4013 - 4022
• Main Authors: Ye, A., Anema, S.G., Singh, H.
• Format: Journal Article
• Language: English
• Published: Savoy, IL Elsevier Inc 01.12.2004; Am Dairy Sci Assoc; American Dairy Science Association
• Subjects: Animal productions; Animals; Biological and medical sciences; disulfide bonds; Disulfides - chemistry; Electrophoresis, Polyacrylamide Gel; fat globules; Fats - analysis; Fats - chemistry; Food industries; Food Preservation - methods; Fundamental and applied biological sciences. Psychology; Glycolipids - analysis; Glycolipids - chemistry; Glycoproteins - analysis; Glycoproteins - chemistry; high pressure; high pressure treatment; Hot Temperature; Lactoglobulins; Membrane Glycoproteins - chemistry; Milk - chemistry; Milk and cheese industries. Ice creams; milk fat globule membrane; Milk Proteins - analysis; Milk Proteins - chemistry; Pressure; reduction; sulfydryl–disulfide interchange; Terrestrial animal productions; Vertebrates; β-lactoglobulin; MFGM; sulfydryl–disulfide interchange; milk fat globule membrane; SMUF; high pressure; β-lactoglobulin; Membrane protein; Physical dressing; Interaction; β-Lactoglobulin; Dairy product; Skimmilk; High pressure; Whole milk; Milk protein; Fat globule; sulfydryl-disulfide interchange; Dairy industry; Membrane; Whey protein; Milk fat
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(04)73542-0

The association of β-lactoglobulin (β-LG) and α-lactalbumin (α-LA) with milk fat globule membrane (MFGM), when whole milk was treated by high pressure in the range 100 to 800MPa, was investigated using sodium dodecyl sulfate (SDS)-PAGE under reducing and nonreducing conditions. In SDS-PAGE under reducing conditions, β-LG was observed in the MFGM material isolated from milk treated at 100 to 800MPa for 30min, and small amounts of α-LA and κ-casein were also observed at pressures >600MPa for 30min. However, these proteins were not observed in SDS-PAGE under nonreducing conditions. These results indicate that β-LG and α-LA associated with MFGM proteins via disulfide bonds during the high-pressure treatment of whole milk. The amount of β-LG associated with the MFGM increased with an increase in pressure up to 800MPa and with increasing time of pressure treatment. The maximum value for β-LG association with the MFGM was approximately 0.75mg/g of fat. Of the major original MFGM proteins, no change in butyrophilin was observed during the high-pressure treatment of whole milk, whereas xanthine oxidase was reduced to some extent beyond 400MPa. In contrast to the behavior during heat treatment, PAS 6 and PAS 7 were stable during high-pressure treatment, and they remained associated with the MFGM.