title: High pressure-induced changes in bovine milk proteins: a review.
abstract: High pressure (HP)-induced changes in the proteins of bovine milk have become an area of considerable research interest in recent years; as a result, there is now a detailed understanding of the effects of HP on casein micelles and whey proteins. HP treatment at pressures >400 or >100 MPa denatures the two most abundant whey proteins, alpha-lactalbumin (alpha-la) and beta-lactoglobulin (beta-lg), respectively. The majority of denatured beta-lg in HP-treated milk associates with the casein micelles, although some denatured beta-lg remains in the serum phase or is attached to the milk fat globule membrane; HP-denatured alpha-la is also associated with the milk fat globules. Casein micelles are disrupted on treatment at pressures >200 MPa; the rate and extent of micellar disruption increases with pressure and is probably due to the increased solubility of calcium phosphate with increasing pressure. On prolonged treatment at 250-300 MPa, reassociation of micellar fragments occurs through hydrophobic bonding; this process does not occur at a pressure >300 MPa, leading to considerably smaller micelles in such milk. As a result of HP-induced changes, the size, number, hydration, composition and light-scattering properties of casein micelles in HP-treated milk differ considerably from those in untreated milk.
authors.affiliation: Department of Food and Nutritional Sciences, University College Cork, Cork, Ireland.
authors.forename: Thom
authors.initials: T
authors.lastname: Huppertz
authors.forename: Patrick F
authors.initials: PF
authors.lastname: Fox
authors.forename: Kees G
authors.initials: KG
authors.lastname: de Kruif
authors.forename: Alan L
authors.initials: AL
authors.lastname: Kelly
mesh_terms: D000818:Animals; D002364:Caseins / Q000737:chemistry; D002417:Cattle; D008823:Micelles; D008894:Milk Proteins / Q000737:chemistry*; D011312:Pressure; D011487:Protein Conformation; D000067816:Whey Proteins
chemical_list: D002364:Caseins; D008823:Micelles; D008894:Milk Proteins; D000067816:Whey Proteins