Definition of starch components in foods by first-order kinetics to better understand their physical basis

Starch-based foods frequently contain different starch digestible fractions, with distinct digestion rates and locations in human upper gastrointestinal tract. Understanding the physical basis for these starch components is critical for developing foods with low glycemic index (GI) values. Conducting first-order kinetics analysis has been able to extract information on starch digestion properties, with solid physical basis. However, there is currently no clear procedure in terms of defining different starch fractions by first-order kinetics analysis. This review proposes that starch-based foods can be categorized as structurally homogenous or heterogenous starch systems by fitting their starch digestograms to the first-order kinetics model, which are characterized by a single set or multiple sets of digestion rate constants and the fractions remaining undigested at long times during in vitro digestion. In line with starch hierarchical structures, it helps understand the structural origins for different starch components in foods, which can ultimately help the development of functional foods with low GI.