ABSTRACT
Against this background, the design and modification of structures and interactions of the major functional and nutritional components of food systems assumes a new significance. Biopolymers are especially important in this respect for a number of reasons. Firstly, the individual protein and polysaccharide molecules are of nanoscale dimensions. Secondly, owing to the special features of their molecular structures (a large number of both polar and non-polar functional groups), they are prone to self-assembly in aqueous media or at interfaces. This self-association is the result of weak non-specific physical bond formation (biopolymerbiopolymer or biopolymer-solute1) in response to changes in pH, temperature, etc., or addition of ions, enzymes, etc. A third reason for the importance of biopolymers is that they comprise the nanoscale building blocks of particles, aggregates, fibres, complexes and networks commonly found in food gels and dispersions (Veerman et al., 2003; Murray and Ettelaie, 2004; Dickinson, 2004, 2006a,b; Graveland-Bikker et al., 2006; van der Linden, 2006; Morris, 2005, 2006; Weiss et al., 2006; Bolder et al., 2006; Zhang et al., 2006; Manski et al., 2007; Huppertz and de Kruif, 2008). Table 1.2 illustrates schematically some examples of nanoparticles based on biopolymers, lipids and surfactants which can be present in the dispersion medium and at interfaces in food colloids.
