Surface Activity of Yolk, Plasma and Dispersions of Yolk Fractions

SUMMARY Undiluted yolk, plasma, and a 4.8% livetin solution had surface tensions of about 44 dynes/cm and interfacial tensions of around 5 dynes/cm. Extensive dilution of the yolk and plasma with either water or 10% NaCl did not bring about marked decreases in the activity of the surfaces. Rehydrated dried yolk had surface energy values similar to those for yolk. Granule suspensions, diluted with water and 10% Nail, had high surface and interfacial tensions. A yolk phospholipid fraction reduced the surface energy of sols to very low values. The contributions of proteins in a livetin fraction and of phospholipids to the surface properties of yolk are discussed.