采用超声波预处理玉米淀粉,研究超声对玉米淀粉分子质量分布的影响,再将超声与传统湿法阳离子淀粉制备工艺结合起来,研究超声预处理法制备阳离子淀粉的工艺条件。采用Box-Behnken中心组合响应面设计,对工艺条件进行优化,并分析超声功率、超声时间、醚化温度、醚化pH值对反应效率的影响。结果表明:超声处理降低了支链淀粉分子质量,提高了阳离子淀粉的反应效率。超声预处理法制备阳离子淀粉的最佳工艺条件为:醚化温度42.58℃,醚化pH值12.03,超声功率150 W,超声时间47.11 min。在此试验条件下实际测得的取代度为0.051 2,反应效率为74.25%。

The ultrasonic wave was used in the pretreatment of corn starch. The ultrasonic effect on the corn starch molecular weight distribution was investigated. The ultrasound technology was then combined with the traditional wet process. The result indicated that the ultrasound treatment decreased molecular weight of amylopectin. The optimum conditions of ultrasonic pretreatment method obtained by response surface design were as follows: reaction temperature 42. 58 ℃,pH 12. 03,ultrasound treatment time 47. 11 min,ultrasonic power 150 W. Under the above conditions,the actual substitution degree was 0. 0512,the reaction efficiency was 74. 25%.