Relationship of Absorptive and Interfacial Behavior of Some Food Proteins to Their Emulsifying Properties

The relationship between surface and interfacial tension of 14 food proteins and their hydrophilic/lipophilic characteristics was studied. Maximum lowering of surface and interfacial tension was achieved when the water‐oil absorption index (WOAI), calculated by measuring the spontaneous water and oil uptake was nearly two; the protein absorbed twice as much water as oil. The ability of a protein to decrease interfacial tension between oil and water was related to its ability to emulsify oil, being determined by the WOAI. However, stability of emulsions was not ensured by a large decrease in interfacial tension.