Retrogradation Behavior of Wheat Starch Gels with Differing Molecular Profiles

Abstract

ABSTRACT Differing molecular profiles of starches were developed by acid treatment of native wheat starch. Molecular weight distribution, branching, and linear chain length distribution was characterized. Starches with fewer large size amylopectin fragments, increased smaller size amylopectin fragments, decreased branch points, decreased overall sizes, and narrower linear chain length distributions, had higher initial retrogradation rates. However, all aged starch gels had similar final crystalline enthalpy levels. Different retrogradation behaviors were due to smaller size amylopectin fragments, narrowed linear chain length distribution, and decreased branching. Retrogradation behavior was modeled using classical Avrami kinetics to allow comparison with other retrogradation studies.