Abstract:

Sodium tripolyphosphate was used as cross-linking reagent to prepare cross-linked corn starch under microwave irradiation. The effects of preparation process parameters such as pH, sodium tripolyphosphate amount and microwave power and irradiation time on sedimentation volume of cross-linked corn starch were investigated by single factor and orthogonal array methods. Results showed that the optimal values of these parameters for reaching the highest sedimentation volume of rosslinked corn starch were pH 10.5, sodium tripolyphosphate amount accounting for corn starch 2.5%, and microwave power 350 W for an irradiation duration of 5 min. Our investigation demonstrates that time consumption for cross-linking reaction of corn starch is largely shortened by using microwave irradiation technique. Therefore, this technique has a promising potential for industrial dry preparation of cross-linked corn starch

Key words: corn starch, dry preparation, cross-linked starch, microwave irradiation