Amylose is considered to be an essentially linear polymer composedalmost entirely of α-1,4-linked D-glucopyranose (Fig. 1-3).Recent evidence, however, has suggested that some branches are presenton the amylose polymer (2). Simplified models for the structureof amylose are shown in Figure 1-4. Although typically illustrated asa straight chain structure for the sake of simplicity, amylose is actuallyoften helical. The interior of the helix contains hydrogen atomsand is therefore hydrophobic, allowing amylose to form a type ofclathrate complex with free fatty acids, fatty acid components of glycerides,some alcohols, and iodine (3).Iodine complexation is an important diagnostic tool for the characterizationof starch and is reviewed in greater detail in Chapter 2.Complexation with lipids, particularly mono- and diglycerides, is awell-known property of the amylose helix. The formation and structuralintegrity of amylose-lipid complexes are functions of variousfactors, including temperature, pH, contact and/or mixing time betweenthe host amylose polymer and the “guest” molecule, and thestructure of the fatty acid or glyceride. The resulting “inclusion com-
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