Formation of egg yolk-modified starch complex and its stabilization effect on high internal phase emulsions

The aim of the present paper was to fabricate egg yolk-modified starch complex at neutral pH as novel emulsifiers to stabilize high internal phase emulsions (HIPEs). Octenyl succinic anhydride (OSA) and hydroxypropyl distarch phosphate (HPDSP) were selected as representative models of surface active and non-surface active polysaccharides. Results of particle diameter, zeta-potential and turbidity indicated that egg yolk-modified starch complex could be formed via electrostatic and hydrophobic interaction. The soluble complex could be formed in egg yolk-OSA starch solutions, which was beneficial to decrease the droplet size and increase the apparent viscosity of HIPEs. However, at the high concentration of HPDSP (3–4 %), the insoluble complex could be formed in egg yolk-HPDSP solutions, which increased the viscosity of water phase and promoted the stability of oil droplets. This work provides a feasible way to successfully fabricate HIPE, which may help to expand their application in the food industry.