AN AQUEOUS ALCOHOLIC-ALKALINE PROCESS FOR CATIONIZATION OF CORN AND PEA STARCHES

To develop a more efficient process for cationization of corn and pea starches, the effects of gelatinization inhibitor, type of solvent and solvent concentration, starch : water ratio, reaction temperature and 2-chloro-3-hydroxypropyltrimethylammonium chloride (CHPTAC) concentra tion on rate and efficiency of cationization of corn und pea starches in an aqueous alcoholic-alkaline solvent were studied during 24h of re action time. The use of watermiscible organic solvents in the aqueous alkaline media eliminated the requirement for a gelatinization inhibit or to minimize starch swelling. The alcohol concentrations which produ ced high reaction efficiencies were 35-75% ethanol or 2-propanol. Opti mum conditions for the reaction included 65% ethanol, 50 degrees C and a starch:water ratio of 1:1 (w/w). The degree of substitution (DS) va lue increased linearly with CHPTAC concentration up to O,2M CHPTAC, bu t reaction efficiency (RE) decreased at the O,2M CHPTAC concentration. Cationization of starch in the aqueous alcohol solvent would be an al ternative to aqueous processes because of the higher DS and reaction e fficiencies that were achieved more rapidly and without the aid of oth er gelatinization inhibitors.