Starch Structure, Properties and Physical Methods of Analysis

This chapter focuses on some aspects of phase transition behavior and other material properties of starch, particularly as they pertain to the structural order and interactions of the starch polysaccharides with water, lipids and other solutes. Understanding the thermally induced structural transitions of starch is helpful in controlling its physical properties and processing behaviors (e.g. plasticization, viscosity), as well as in designing products with improved properties (e.g. texture, stability). 

Starch Structure, Properties and Physical Methods of Analysis 

Ordered and Amorphous Structural Domains (See Also Chapters 5 and 6) 

Long-range ordering (crystallinity) in starch granules is demonstrated by x-ray diffraction (Chapter 6). WAXD patterns of starches correspond to one of the two limiting polymorphs (A or B) or the combination C form, the C-pattem being a superposition of A- and B-patterns.28 29 The A form is typical of cereal starches, while 

Other WAXD starch patterns, known as V-types, are associated with the amylose fraction. In V-amylose, the chain conformation is a left-handed single helix with six residues per turn (V6) for complexes with aliphatic alcohols and monoacyl lipids with ligands bulkier than a hydrocarbon chain, helices of seven or eight glucose residues per turn are feasible.31 Aliphatic chains within amylose helices are rather locked 

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