Structural features of starch–lactone inclusion complexes in aqueous potato starch dispersions: the role of amylose and amylopectin

Abstract

Starch, in particular the linear amylose, is able to form inclusion complexes with a wide spectrum of ligand molecules, among them flavor compounds such as lactones. The structural properties of potato starch dispersions with lactones were followed with oscillatory measurements, amperometric iodine titration, X-ray diffraction measurements, and light microscopy. The complexation of starch influences the structural properties of starch dispersions at different length scales. At the macroscopic level, the unfavourable interaction of amylose–lactone complexes with water promotes gelation or phase separation, and amylose–lactone complexation leads to spherulitic crystallization. Amylopectin–lactone interactions are thought to contribute to the long-term behavior of starch dispersions. Thereby, the colloidal properties of starch dispersion and spherulite morphology are determined by the type of lactone and the kinetics of starch complexation.