Protein denaturation and emulsifying properties of plasma and granules of egg yolk as related to heat treatment

Solubility, electrophoresis, viscosity and emulsifying properties of heated solutions of yolk, plasma and granules were determined, Plasma and yolk we re not effected when heated under 69 degrees C, Above 69 degrees C, protein solubility dropped sharply and apparent viscosity rose sharply because of aggregation of proteins. For granules, protein solubility and apparent visc osity were not modified up to 76 degrees C, The constituents of granules we re not denatured. Emulsifying activity of yolk and plasma decreased after h eating at 72 degrees C but remained steady for granules, Emulsion stabiliza tion properties of yolk, plasma and granules were not influenced up to 76 d egrees C, Results suggested that intact granules withstood more severe heat treatments than egg yolk without lessening their emulsifying properties.