Perspectives of Starch in Food Science

Starch is amongst the most abundant plant products and is a mixture of two polymers, amylose and amylopectin. During food processing starch is transformed by hydrothermal treatments. The structural features of starch in food cover a size range of more than six orders of magnitude and encompass the macromolecules, crystalline domains, phase separated amylose and amylopectin structures, starch granules and extensive starch networks. The structure of starch is also influenced by specific and non-specific interactions with other food constituents and ingredients. Starch, particularly amylose, is able to specifically interact with small ligands and form helical inclusion complexes that influence the colloidal properties of aqueous food systems. Furthermore, the nutritional properties of starch, for instance the amount of resistant starch, which is not digested in the upper human gastrointestinal tract, but fermented by the colonic microflora, are determined by food composition and processing conditions. An in-depth understanding of the relationships between processing and structure of starch taking into account the different structural levels will allow the prediction and control of bulk properties of food including textural, sensory and nutritional properties.