Surfactant-based self-assembly of polysaccharides

Let us consider now the case of a specific ionic polysaccharide. The unique properties of complexes of the cationic chitosan with non-ionic sorbitan esters provides an interesting example. Grant and co-workers (2006) have established that mixtures of chitosan and surfactant form emulsion-like solutions and/or creams, where the surfactant component is present as droplets or micelle-like particles and the chitosan solution acts as the system s continuous phase. It was established that the length and the degree of saturation of the surfactant hydrocarbon chain have a significant impact on the development of the chitosan-surfactant complexes. Moreover, an optimal distance between the chitosan s protonated amine groups is required for effective interactions to occur between the polysaccharide and the sorbitan esters. 

According to Groot (2000), the mechanism of interaction between a polymer and surfactant may be deduced by considering parameters such as polymer size, mode of surfactant adsorption (continuous or discrete micelles), and possible sites of interaction (head group or tail). For the case of the mechanism of the interaction between chitosan and sorbitan esters, the polymer concentration (dilute, semi-dilute, concentrated) of 

There are many other examples of the potential use of mixed systems of chitosan + surfactants to be found in the recent research literature. For instance, it has been established that chitosan-surfactant interactions can be successfully used for preparing emulsions stabilized by multilayer adsorbed films (Mun et al., 2006 Chuah et al., 2009). 

Manipulation of Food Colloid Properties through Biopolymer Self-Assembly 

There is now a solid body of available knowledge to indicate that the general features of biopolymer self-assembly in bulk aqueous solutions can account for various detailed aspects of the stability, rheology and microstructure of oil-in-water emulsions (and foams) stabilized by the same kinds of biopolymers (Dickinson, 1997, 1998 Casanova and Dickinson, 1998 Dickinson et al., 1997, 1998 Semenova et al., 1999, 2006 van der Linden, 2006 Semenova, 2007 Ruis et al., 2007). In particular, the richness of the self-assembly and surface-active properties of the 

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