Cationization of Waxy and Normal Corn and Barley Starches by an Aqueous Alcohol Process

Abstract

Abstract When an aqueous alcoholic‐alkaline solvent was used, cationization of normal and waxy corn and barley starches was achieved with high degrees of substitution (DS) and reaction efficiency (RE) in the absence of gelatinization inhibitor salts. Ethanol was a more effective solvent than methanol or 2‐propanol, and alcohol concentrations could vary between 35–65%. Maintaining a starch to water ratio of 1:1 (w/w) was critical, but DS values were proportional to the concentration of cationic reagent, 3‐chloro‐2‐hydroxypropyltrimethylammonium chloride. At 50°C, cationization was essentially complete within 6h but nearly the same DS could be achieved in 1h at 70°C.