Abstract Fourier transform ir spectroscopy has been used to study the gelation and retrogradation of amylose and amylopectin. Results indicate that two processes occur: a fast change complete within 0.5 h shown by both samples and a much slower change that continues up to 400 h seen only for amylopectin. These processes are related to changes in molecular conformation, and are explained in terms of existing models for gelation and retrogradation in amylose and amylopectin.