Abstract:  The starch was pretreated with a-amylase and then acetylated. The effects of the main parameters on the product properties were analysed. The results indicated that the DS value of the product and acetylation efficiency increased about 40% and 30% respectively after the enzymatic pretreatment under 38T, 0.3 % of ratio of [E] / [S] for 60min. Within wide PH value range, the ηapp of the product showed no significant varyation. Thus, the technological condition and product properties got improved. This approach can be conjointed into the present process readily.

Key words: Anyloacetate a-Amlyase Degree of Substitution (DS) Dextrose equivalent (DE) Apparent viscosely (&eta, app)；