The effects of protein polymerization in whey protein isolate- stabilized emulsions on emulsion properties were investigated. Polymerization, involving intermolecular disulfide bonds between whey proteins adsorbed at the oil-water interface, increased with increasing storage time following emulsion formation. Ageing resulted in increased aggregation of emulsion droplets, emulsion viscosity and susceptibility to creaming but these effects were lower when thiol-disulfide interchange reactions were inhibited by N-ethylmaleimide (NEM). Following heating to 75°C, disulfide-mediated polymerization of whey proteins increased as did droplet aggregation, emulsion viscosity and creaming. While NEM lowered the extent of disulfide-mediated polymerization it did not affect the measured physical properties of the heated emulsions. Non-covalent interactions appeared to be the principal forces leading to aggregation of emulsion droplets but aggregates once formed were stabilized by disulfide bonds.
|Original language||English (US)|
|Number of pages||10|
|Journal||Advances in Experimental Medicine and Biology|
|State||Published - 1997|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)