Chemistry of starch

For more about starch see The Other Double Helix— The Fascinating Chemistry of Starch in the August 2000 issue of the Journal of Chem ical Education pp 988-992... 

The chemistry of starches, galactomannans, modified starches, modified celluloses and alginates is discussed in section 10.8.1 on natural thickeners. The main starches used are... 

Perhaps the most important advance in the chemistry of starch was the realization of the apparent inhomogeneity of the material, followed by its fractionation into simpler components—first carried out quantitatively by Schoch1 in 1941. Starches can, in general, be separated into at least two chemically distinguishable entities amylose, a mixture of essentially unbranched chains, and amylopectin, a mixture of highly branched chains.2... 

Although the basic chemistry of starches is the same in every plant, the starches of different plants are different to each other. Potato starch contains about 21% of... 

Greenwood, C. T., Aspects of the Physical Chemistry of Starch, 11, 335-385 Greenwood, C. T., The Size and Shape of Some Polysaccharide Molecules, 7, 289-332 11, 385-393 Greenwood, C. T., The Thermal Degradation of Starch, 22,483-515 Greenwood, C. T., and Milne, E. A., Starch Degrading and Synthesizing Enzymes A Discussion of Their Properties and Action Pattern, 23, 281-366... 

The discovery of the V-type, helical amylose (see p. 265) that forms when amylose interacts with 1-butanol was crucial for the development of the chemistry of starch inclusion complexes. It soon appeared that 1-butanol complexes solely with the amylose component. This selectivity became the first convenient method of fractionating starch. This method was first described by Schoch699 and later developed by Kerr et al.700-702 and oth-ers 680,703 An impr0ved procedure was subsequently patented.704 The amount of 1-butanol adsorbed in amylose is increased by the presence of moisture and is also dependent on two key factors the time of contact with that alcohol and the origin of the amylose, as shown in Table XXIX. 

In this connection it should be pointed out that maltotriose, a trisaccharide with two maltose linkages, is not attacked by j3-amylase, but is fermented by common yeasts. This has possibly caused some confusion in the chemistry of starch degradation. 

But, from about this time, near the turn of the century, the industry—if not the chemistry—of starch nitrate took a great step forward. It seems to have begun, particularly in the United States, with the work of Arthur... 

The chemistry of starch ethers has progressed with the use of a greater variety of alkylating agents, for instance, ethylene oxide,745 chloroacetic acid, epichloro-hydrin, vinyl monomers, and other alkylating agents.746... 

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