title: Interactions of casein micelles with calcium phosphate particles.
abstract: Insoluble calcium phosphate particles, such as hydroxyapatite (HA), are often used in calcium-fortified milks as they are considered to be chemically unreactive. However, this study showed that there was an interaction between the casein micelles in milk and HA particles. The caseins in milk were shown to bind to the HA particles, with the relative proportions of bound β-casein, αS-casein, and κ-casein different from the proportions of the individual caseins present in milk. Transmission electron microscopy showed no evidence of intact casein micelles on the surface of the HA particles, which suggested that the casein micelles dissociated either before or during binding. The HA particles behaved as ion chelators, with the ability to bind the ions contained in the milk serum phase. Consequently, the depletion of the serum minerals disrupted the milk mineral equilibrium, resulting in dissociation of the casein micelles in milk.
authors.affiliation: Riddet Institute, Massey University , Private Bag 11 222, Palmerston North 4442, New Zealand.
authors.forename: Lucile
authors.initials: L
authors.lastname: Tercinier
authors.forename: Aiqian
authors.initials: A
authors.lastname: Ye
authors.forename: Skelte G
authors.initials: SG
authors.lastname: Anema
authors.forename: Anne
authors.initials: A
authors.lastname: Singh
authors.forename: Harjinder
authors.initials: H
authors.lastname: Singh
mesh_terms: D000818:Animals; D002130:Calcium Phosphates / Q000737:chemistry*; D002364:Caseins / Q000737:chemistry*; D002417:Cattle; D008823:Micelles; D008892:Milk / Q000737:chemistry*; D011485:Protein Binding
chemical_list: D002130:Calcium Phosphates; D002364:Caseins; D008823:Micelles; C020243:calcium phosphate