Effect of Purification Methods on Rice Starch Structure

Various methods for obtaining and purifying rice starch from white rice were examined and compared. Processed starch was then debranched with isoamylase and the molecular weight distribution of the branches analysed by gel-permeation chromatography (GPC). The distribution of the chain lengths was compared between methods to quantify any damage sustained by the starch during purification. Effectiveness of protein removal was also determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A combination of defatting and protein removal methods was shown to be useful in the purification of rice flour into starch and presented significant advantages over other reported methods.