Physicochemical and Functional Properties of Dioscorea alata L. cv “Brazo” Starch during post-harvest Storage

Abstract

This study was conducted in order to assess the changes in physicochemical and functional properties of starch of Dioscorea alata L. cv “Brazo“ during the post-harvest storage. Tubers were obtained from the experimental farm of University Nangui Abrogoua (Abidjan, Côte d’Ivoire) in West Africa. The results showed that the physicochemical properties of starches such as lipids, proteins and ash did not vary while amylose and amylopectin decreased during the storage time. However, the functional properties did not change significantly during the seven months of storage time. Starches showed a high degree of swelling and solubility and less syneresis when subjected to refrigeration or freezing. The viscoamylogram diagrams of the starch pastes did not give a viscosity peak, but had viscosities that increased during the heating and cooling cycle, suggesting thermo-stability and high retrogradation tendency during cooling. The pasting temperature was high and ranged between 72 and 77 °C. The pasting and cooking time were 20 and 30 min respectively.