Towards an understanding of starch granule structure and hydrolysis

Abstract

Starch constitutes a major component of foods and also a raw material for use in the production of industrial products. The constituent macromolecules of starch are packaged in a highly ordered and compact manner, resulting in inert, insoluble granules. Food processing destroys starch structure, thereby releasing the component molecules, which are subsequently made available for hydrolysis or serve a functional role in the food system. The application of starch as a raw material usually requires the prior disruption of the inert granule structure, which involves additional processing steps. The hydrolysis of native granules has ramifications at all levels of the food processing chain, from postharvest losses to nutritional consequences of the ingested food. Technologists have not been able to take advantage of, or control, this process because the body of the information that is available on starch granule structure and the behaviour of hydrolysing enzymes is still incomplete. In this review, I have highlighted some of the more recent advances in this field, with the view to opening up the way for more efficient native starch hydrolysis.