Polysaccharides in Food Emulsions

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Polysaccharides are important ingredients in many food products. In particular, polysacchar-

ides are found in the ingredients of a wide range of food emulsions, such as mayonnaise and

ice-cream [1]. The relevant functionalities originate from several molecular properties of the

polysaccharides and their interaction with emulsion droplets and other components in the

food systems [2,3]. Whereas proteins are present primarily as emulsion forming and stabiliz-

ing agents, soluble polysaccharides primarily function as thickening and water-holding

agents. Polysaccharides can be used in their natural form, but in many cases the functionality

is adapted by chemical modifications, for example, to improve the solubility and water-

binding capacity. A wide range of properties are found among the whole group of polysac-

charides [4], varying from insoluble forms (cellulose) to high swelling power and solubility

(starch, guar gum), low viscosity (gum arabic) to high viscosity (guar gum), and nongelling

(dextran) to gelling (agar). Gel formation is often thermo-reversible and the gel may melt on

heating (alginates, pectin) or set on heating (some cellulose derivatives).