Skim Milk Acidification

✍ Scribed by C.G. de Kruif

• Book ID: 102577548
• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 183 KB
• Volume: 185
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1996.4548

✦ Synopsis

Skim milk was acidified slowly using glucono-delta-lactone and HCl. On lowering the pH the steric stabilization of the casein micelles diminishes and as a result the micelles exhibit attractive interactions. These interactions can be quantitatively described using an adhesive hard sphere (AHS) model. The strength of the attraction is found to be proportional to 1/(pH - pC); it is suggested that pC may be related to an effective dissociation constant of the carboxylic acid groups along the kappa-casein backbone. If pH approaches pC, the polyelectrolyte-like kappa-casein brush collapses onto the surface of the micelles. The AHS model is quantitatively tested using viscosity and dynamic light scattering measurements.