Antistaling of Rice Starch in a Gel Model System and Korean Rice Cake: the Role of Wheat Flour in Retrogradation-Retardation Technology

Abstract

This study focused on the mechanisms of retrogradation-retardation technology for applications in garaetteok (steamed and extruded cylinder-shaped rice cake) production. Based on the comparison of conventional and retrogradation-retardation methods, the addition of raw wheat flour was selected as a key process. The rheological properties of gelatinized rice starch pastes after treatment with raw or autoclaved wheat flour and Novamyl L were investigated. Among them, raw wheat flour and Novamyl L resulted in significantly lowered the elastic modulus. The textural properties of garaetteok treated with raw or autoclaved wheat flour were examined by texture profile analysis (TPA) during storage for 3 days at 4 degrees C. The hardness of garaetteok made with raw wheat flour was maintained for up to three days. In contrast, autoclaved wheat flour did not affect elastic modulus or hardness. As a result raw wheat flour effectively retards starch retrogradation through starch hydrolysis induced by amylase in wheat flout