ABSTRACT
The amphiphilic character of proteins makes them surface-active at many different types of interfaces. This capacity of proteins to accumulate and form films at phase boundaries (solid-liquid, liquid-liquid, and liquidvapour) has enormous implications for biological processes such as blood clotting, cell adhesion, lung expansion-contraction, activation of metabolic process, etc.. And it also has implications for the technological processes involved in the manufacture of food foams and emulsions (Damodaran, 2004). Hence, for a long time the related subjects of protein adsorption at interfaces and protein interactions with other surface-active molecules (e.g., small-molecule surfactants) have attracted considerable attention. In addition, the phenomenon of electrostatic protein-polysaccharide complexation at the interface has attracted more recent research attention. This is because of its potential use in the nanoscale engineering of delivery vehicles for nutrient encapsulation, and also in the possible protection of adsorbed proteins and emulsified lipids against enzymatic breakdown during digestion (Guzey and McClements, 2006; McClements et al., 2008; Dickinson, 2008; McClements and Decker, 2009).
