Resistant starch analysis

Goni I, Garcia-Diz L, Manas E and Saura-Calixto F. 1996. Analysis of resistant starch A method for foods and food products. Food Chem 56 445 149. 

The protocol developed by Holm et al. (1986) was evaluated by analysis of starch content in wheat starch, white wheat flour, whole-grain wheat, and industrially processed wheat products. The major advantage of this protocol over the Basic Protocol is its reduced cost. The chemicals for the reagent preparations and the enzymes are purchased directly from the companies that produce them. The original method did not include RS3 (resistant starch) in its quantitation. A DMSO treatment step has been added (step 4) to solve this problem. 

That the analysis and labelling of dietary carbohydrates, for whatever purpose, be based on the chemical divisions recommended. Additional groupings such as polyols, resistant starch, non-digestible ohgosaccharides and dietary fibre can be used, provided the included components are clearly defined. 

Mathers JC, Movahedi M, Macrae F, et al. Long-term effect of resistant starch on cancer risk in carriers of hereditary colorectal cancer an analysis from the CAPP2 randomised controlled trial. Lancet One. 2012 13 1242-1249. 

Eerlingen RC, Delcour A. Formation, analysis, structure and properties of type RS3 enzyme resistant starch. J Cereal Sci 1995 22 129-138. 

In recent years, there has been increasing interest in those carbohydrates that escape absorption in the small intestine and enter the colon, where they may have specific health benefits due to their fermentation by the colonic microflora and their effect on gut physiology. This entry considers the definition, classification, dietary sources, methods of analysis, colonic fermentation, and health benefits of both resistant starch and oligosaccharides, and compares them with those of dietary fiber. 

Starch in foods has been analyzed mainly by enzymatic hydrolysis to free the glucose followed by its specific determination. From a nutritional standpoint, starch is present in foods as digestible and RS. RS is that which is not absorbed in the small intestine of healthy humans. From an analytical standpoint, the distinction between digestible and resistant is unclear (Bjbrk, 1996). Nevertheless, RS is virtually insoluble in water and techniques for analyzing total starch in foods have employed either an alkaline (KOH) or organic solvent (DMSO) treatment to successfully disperse the crystalline starch fractions and keep them solubilized. Quantitative analysis of RS in foods has utilized enzymes for their determination (Bjork, 1996). Nevertheless, techniques for analyzing RS in foods need to be established and tested in formal collaborative studies. 

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