Starch, digestion structure

Lo Piparo E, Scheib H, Frei N, Williamson G, Grigorov M, Chou CJ. 2008. Flavonoids for controlling starch digestion Structural requirements for inhibiting human alpha-amylase. J Med Chem 51 3555-3561. 

Lehmann, U., Robin, F. (2007). Slowly digestible starch-its structure and health implications a review. Trends in Food Science and Technology, 18, 346-355. 

Hamaker, B. R., Zhang, G., Ao, Z. (2008). Starch digestion properties moderated through structure and form, 58th Australian Cereal Chemistry Conference, 31 August-4 September. Surfers Paradise, Australia. 

Feedstuffs consist largely of complex polymers (e.g. proteins, starches, fats) that must be hydrolyzed to the constituent building blocks before they can be absorbed and made available to the host. The digestibility of many plant proteins is inherently lower compared to proteins from animal tissues. This is particularly true for the structural proteins (Carbonaro et al, 2000 Mariotti et al, 1999). As a consequence, amino acid scores for many plant proteins often do not reflect true availability to the host (Mariotti et al, 2001). 

In developed countries, carbohydrate provides about 45% of the energy ingested. It comprises starch, sncrose, lactose, fmctose and glucose with traces of maltose and trehalose. The structure of these carbohydrates and how they are digested, absorbed into the bloodstream and further metabolised is described in Chapters 4 and 6. 

Bender, H., Siebert, R., Stadler-Szoke, A. (1982). Can cyclodextrin glycosyltransferase be useful for the investigation of the fine structure ofamylopectins Characterisation of highly branched clusters isolated from digests with potato and maize starches. Carbohydr. Res., 110,245-259. 

An understanding of physicochemical and structural properties of starch will offer the possibility to control the quality of potato and potato products (e.g. digestibility), and to produce new potato starches with added value. As a result, it is critical to understand and apply advanced analytical techniques to characterize and evaluate the quality of potatoes and potato starch. In this chapter, the advanced analytical techniques to evaluate the quality of potatoes and potato starch are introduced and discussed in detail. 

Intrinsic factors that may influence potato digestibility include the structure of the starch molecules, the structure of starch granules, the composition of the potato, the presence of phosphate in starch granules, tissue structure, and factors that may affect these, including agronomic and growth history, storage, maturity, and variety. 

Meaning Is analytically measured as sugars soluble after amylase digestion of finely ground samples, so consists of food sugars and digested starch. But it represents potential availability rather than true availability because fine grinding removes the constraints of food structure. 

Singh and Preiss265 concluded that, although some homology exists between the three starch-branching enzymes, there are major differences in the structure of BEI when compared to BEIIa and BEIIb, as shown by its different reactivity with some monoclonal antibodies and differences in amino acid composition and proteolytic digest maps. 

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