干热处理对淀粉-壳聚糖共混物物化性质影响

Effect of dry-heating on the physicochemical properties of waxy maize starch-chitosan mixture

该实验以蜡质玉米淀粉为原料,将其与壳聚糖共混经喷雾干燥制备初步样品,再在一定条件下经过干热处理制得淀粉―壳聚糖共混物。利用扫描电子显微镜、RVA、FTIR、激光粒径分析仪等现代分析技术研究了干热前后这两种共混物的物化性质,结果表明:该淀粉―壳聚糖共混物干热处理前后,扫描电镜观察这两种样品的形态并没有明显差异,但在这两种样品中均显示出壳聚糖成薄膜状均匀覆盖于淀粉颗粒的表面。糊化特性、粒径以及红外波谱的测定均显示出这两种样品性质明显不同,这表明干热处理使淀粉―壳聚糖共混物的结构发生了变化,其中之一为淀粉与壳聚糖发生了交联。

Experimental samples were prepared through the crosslinking between waxy maize starch and chitosan using a dry-heating method. The physicochemical properties of the sample was measured by the RVA,FTIR,SEM and Laser Diffraction. SEM showed that starch granules were covered by chitosan and adhered with each other,leading to the size distribution of the samples getting bigger than the raw starch granules. Dry-heating treatment resulted in the reduction of viscosity because of the interaction between starch and chitosan. FTIR spectrum confirmed that crosslinking between the two components occurred.