Amylopectin, composition

The blue reaction is very useful in determining the amylose-amylopectin composition of starch,69,196,277 and in controlling of the effect of mechano-chemical and enzymic treatment and fractionation of starch79,71,204,278-289... 

Bertoft, E. (2007a). Composition of clusters and their arrangement in potato amylopectin. Carbohydr. Polym., 68, 433 46. 

Yusuph, M., Tester, R. F., Ansell, R., Snape, C. E. (2003). Composition and properties of starches extracted from tubers of different potato varieties grown under the same environmental conditions. Food Chem., 82,283-289. Zhu, Q., Bertoft, E. (1996). Composition and structural analysis of alpha-dextrins from potato amylopectin. Carbohydr. Res., 288, 155-174. 

Potato starch exhibits different granular stmcture and composition, as opposed to cereal starches, which are responsible for the variation in functional behavior of these starches. Cereal starches exhibit the t5 ical A type X-ray crystalline pattern, whereas potato starch shows the B-form, andlegumesthe mixed state pattern C . The A, B, and C patterns are the different polymeric forms of starch that differ in the packing of amylopectin double helices. The structure of potato starch is discussed in more detail in Chapter 4. 

A second very widely distributed polysaccharide is starch, which is stored in the seeds, roots, and fibers of plants as a food reserve — a potential source of glucose. The chemical composition of starch varies with the source, but in any one starch there are two structurally different polysaccharides. Both consist entirely of glucose units, but one is a linear structure (amylose) and the other is a branched structure (amylopectin). 

Li, J.H., Vasanthan, T., Rossnagel, B. and Hoover, R. (2001) Starch from hull-less barley I. Granule morphology, composition and amylopectin structure. Food Chemistry 74, 395-405. 

The mature kernel phenotype for su2 wx is similar to that for wx (Table 3.3). Mature272 and immature270 kernel dry weights and carbohydrate compositions are similar to those of the single mutants. The wx mutant is epistatic to su2, resulting in starch with approximately 100% amylopectin (Table 3.6). The amylopectin of su2 wx... 

White et al.8,30,31 have, in several papers, studied the chemical composition of oat starch amylose and amylopectin (Table 15.2). Gel permeation chromatography (GPC) of the total starch gave rise to two peaks, but some of the material had an unusual iodine affinity and was, therefore, described as an intermediate fraction.8... 

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