Abstract: The preparation and properties of acetylated acid hydrolysis modified starch by using corn starch as raw materials, hydrochloric acid as acid hydrolysis reagent, acetic anhydride as acetylation reagent and sodium hydroxide as catalyst, were introduced in this paper. The effect of some factors such as acid hydrolysis time, acid hydrolysis temperature, concentration of hydrochloric acid and pH on fluidity and substitution degree of modified starch was discussed. The results showed that the increase of acid hydrolysis temperature, time and concentration of hydrochloric acid speeds the starch hydrolysis. The viscosity of acid modified starch was determined by fluidity method. The substitution degree of compound modified starch was determined by acid and alkali titration method.

Key words: starch, acetylation, acid modified starch, preparation, property