Colloidal aggregate networks

This theory was first developed for colloidal aggregate networks and was later adapted to fat crystal networks (52-54). In colloidal systems (with a disordered distribution of mass and statistical self-similar patterns), the mass of a fractal aggregate (or the distribution of mass within a network), M, is related to the size of the object or region of interest (R) in a power-law fashion ... 

Fig. 2. Putative microstructure of a fractal colloidal aggregate network.

Buscall, R., Mills, P.D.A., Goodwin, J.W., and Lawson, D.W. (1988). Scaling behaviour of the rheology of aggregate networks formed from colloidal particles. J. Chem. Soc., Faraday... 

Usually acid- and base-catalysed gelation produces materials having very different textural properties. Microporous materials are generally obtained by acid-catalysed gelation, which forms low cross-linked gel network. While mesoporous materials are obtained by base-catalysed gelation, which forms high cross-linked gel network or colloidal aggregates (12, 13). 

Buscall, R., P.D.A. Mills, J.W. Goodwin, and D.W. Lawson, Scaling Behaviour of the Rheology of Aggregated Networks Formed from Colloidal Particles, J. Chem Soc. Faraday Trans. 1 84 4249-4260 (1988). 

These systems are widely used in many food products. A section will be devoted to the interfedal phenomena in food colloids, in particular their dynamic properties and the competitive adsorption of the various components at the interlace. The interaction between proteins eind polysaccharides in food colloids will be briefly described. This is followed by a section on the interaction between polysaccharides and surfactants. A short review will be given on surfactant association structures, microemulsions and emulsions in food [3]. Finally, the effect of food surfactants on the interfacial and bulk rheology of food emulsions will be briefly described. The formation of aggregation networks and the application of fractal concepts is then considered. This is followed by a section on applications of rheology in studying food texture and mouth feel. 

FI . 16 An aggregated colloidal structure. Neighboring particles touch each other and a complicated network builds up. 

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