A Study on Emulsification Properties of Whey Protein Isolate-Dextran Conjugate

Significant changes in A294and browning intensity showed that whey protein isolate(WPI)-dextran conjugate was successfully formed using dry-heating treatment via Maillard Reaction. The emulsification properties of WPI were significantly enhanced by the covalent attachment of hydrophilic dextran. In the glycoprotein-stabilized emulsions,hydrophobic protein moiety firmly attached to the oil droplet surface and the bulky hydrophilic part of covalently linked polysaccharide highly oriented to the water phase,which was supposed to provide a steric stabilizing layer to inhibit the coalescence of the oil droplets. Obviously,the conjugate G150 had better emulsifying capabilities than initial WPI at the pH range of 3 to 10. The emulsifying capability could be enhanced when the G150 solution was heated at 90°C for 10min.Moreover,there was no decrease in the emulsifying capability of G150 solution when high salinity was added.