Mixed proteinaceous emulsifiers: review of competitive protein adsorption and the relationship to food colloid stabilization

The importance of competitive protein adsorption in the formation and stabilization of food emulsions and foams is examined from both experimental and theoretical standpoints. Issues and problems relevant to mixed protein systems are discussed: the relationship to synthetic polymer adsorption. the effects of labelling and modification. interactions with polysaccharides and lipids and the topics of irreversibility and polydispersity. Information on mixtures of (i) blood plasma proteins and (ii) milk proteins is reviewed in detail. Surface hydrophobicity is discussed in relation to protein surface-activity and resulting emulsifying and foaming capacity. Surface rheological behaviour of adsorbed protein films is discussed in relation to emulsion and foam stability.