淀粉基微球的滴入法制备及性质

Preparation and characterization of starch-based microspheres by dropping method

摘要:

以玉米淀粉、糯玉米淀粉、木薯淀粉三种天然淀粉为原料，高温糊化后以滴入法制备淀粉基微球。考察淀粉种类、淀粉浓度、针头孔径对成球的影响，发现微球粒径随着淀粉浓度和针头孔径的增大而增大，相同淀粉浓度和针头孔径时玉米淀粉基微球的粒径最大。淀粉基微球形貌均一，收率均可达到90%以上，粒径介于1.0~1.5 mm，内部均存在不同程度的中空结构。淀粉基微球较天然淀粉糊化放热峰基本消失、晶型改变且结晶度显著降低。玉米淀粉基微球α-淀粉酶24 h酶解率较玉米淀粉更高，且亚甲基蓝玉米淀粉基微球在30°C~90°C水溶液中加热1 h后均能实现59.28%以上的释放率，说明有利于负载各类亲水性物质。 关键字：淀粉；淀粉基微球；滴入法；粒径；结晶度；释放

Abstract:

Three kinds of natural starch, corn starch, waxy corn starch and cassava starch, were used as raw materials to prepare starch-based microspheres by dropping method after high temperature gelatinization. The effects of starch type, starch concentration and needle aperture on microsphere formation were investigated. It was found that the particle size of the microspheres increased with the increase of starch concentration and needle aperture, and the corn starch-based microspheres showed the largest particle size at the same starch concentration and needle aperture. The starch-based microspheres have uniform morphology, and its yield can reach more than 90%. The particle size of the microspheres was 1.0~1.5 mm, and they had different degrees of the hollow structure. Compared with the natural starch, the gelatinization exothermic peak of starch-based microspheres basically disappeared, the crystal type changed and the crystallinity decreased significantly. The α-amylase enzymolysis rate of corn starch microspheres was higher than that of corn starch at 24 h, and the release rate of the loaded Methylene blue corn starch based microspheres could reach more than 59.28% after heating in aqueous solution at 30°C ~90°C for 1 h, indicating that they were beneficial to load various hydrophilic substances.