Size-separation characterization of starch and glycogen for biosynthesis-structure-property relationships.

Starch and glycogen are highly branched polymers of glucose of great importance to humans in managing and mitigating nutrition-related diseases, especially diabetes and obesity, and in industrial uses, for example in food and paper-making. Size-separation characterization using multiple-detection size-exclusion chromatography (SEC, also known as gel-permeation chromatography, GPC) is able to furnish substantial amounts of information on the relationships between the biosynthesis, processing, structure, and properties of these biopolymers, and achieves superior characterization for use in industrial product and process improvements. Multi-detector SEC is able to give much more information about structure than simple averages such as total molecular weight or size; the detailed information yielded by this technique has already given new information on important biosynthesis-structure-property reactions, and has considerable potential in this field in the future. However, it must be used with care to avoid artifacts arising from incomplete dissolution of the substrate and shear scission during separation. It is also essential in interpreting data to appreciate that this size-separation technique can only ever give size distributions, never true molecular weight distributions. Other size-separation techniques, particularly field-flow fractionation, require substantial technical development to be used on undegraded native starches.