Flocculation and competitive adsorption in a mixed polymer system - Relevance to casein-stabilized emulsions

In a colloidal system containing two chemically similar adsorbable polymers, one a good steric stabilizer, and the other not so good, the state of flocculation of the polymer-coated particles is determined by the competitive adsorption behaviour of the polymer. The key factors controlling the limits of stability can be expressed in terms of a simple model based on a system of sticky hard spheres. Evidence is presented-to support the hypothesis that this approach may be useful in understanding the stability of oil-in-water emulsions containing a mixture of the milk proteins alpha(s1)-casein and beta-casein under conditions of moderate ionic strength.