Study on Preparation and Properties of Hydroxypropyl Wheat Starches

Hydroxypropyl wheat starches were prepared by the etherification reaction of wheat starch with propylene oxide as an etherification reagent.The influences of amount of propylene oxide,sodium hydroxide,and swelling inhibitor,and reaction time on the molar degree of substitution(MS) were studied by applying orthogonal design experiments.The results indicate that the hydroxypropyl wheat starch with higher MS of 0.055 can be pre-pared under the conditions of: 30% propylene oxide,1.5% sodium hydroxide,15% sodium sulfate,and reaction time of 16 hours.Characters of the product,such as the index of transparency,retrogradation,salt residance,and acid residance,were detected.