Effect of interface composition on gel strength and water holding capacity of emulsion-filled whey protein gels

Effect of different environmental conditions including different p H ( 3, 7) , different concentration of sodium chloride (50, 200mmol/L) and heat treatment (90℃, 30min) on stability of emulsions prepared using different emulsifiers (WPI, Tween20, Tween +potato protein hydrolysate) by gravitational separation methods were investigated. Emulsions prepared using different emulsifier including WPI, Tween20 and Tween +potato protein hydrolysate by high speed homogenization method were used as solvent to prepare protein gels. Heat set emulsion-filled whey protein gels were prepared at the protein concentration of 12% (w/v) at different p H (3, 7) and concentration of Na Cl (50 and 200mmol/L) by heating at 90℃ for 30 min. Results showed that gel strength and water holding capacity of gel prepared using emulsion as solvent were higher than the gel prepared with water. Adding sodium chloride could effectively improve the strength and water holding capacity of the gel. It was shown that environmental conditions including p H and salt had effect on gel strength of emulsion-filled whey protein gels. Moreover, emulsion properties had effect on water holding capacity and gel strength of emulsion-filled whey protein gels.