交联和羟丙基改性对蜡质玉米淀粉糊性能的影响

Effects of crosslinking and hydroxypropylated modification on properties of waxy starch

本研究采用蜡质玉米淀粉为原料,湿法工艺制备了磷酸酯双淀粉(1412)、羟丙基淀粉(1440)和羟丙基二淀粉磷酸酯(1442),通过对蜡质玉米淀粉(WS)和3种变性淀粉(1412、1440、1442)在黏度、抗剪切、耐酸性、冻融稳定性和透明度等性能的比较,探讨了羟丙基醚化和交联改性处理对蜡质玉米淀粉糊性能的影响。试验结果显示:⑴羟丙基改性处理降低了淀粉的糊化温度,提高了淀粉峰值黏度,透明度和冻融稳定性得到显著改善,但热稳定性、耐酸性和抗剪切均较差;⑵磷酸盐交联改性的磷酸酯双淀粉糊化温度升高,峰值黏度降低,糊液在抗剪切、耐酸性方面得到显著改善,但糊液透明度降低,冻融稳定性未得到改善;⑶通过交联和羟丙基改性的羟丙基二淀粉磷酸酯,兼具有磷酸酯双淀粉和羟丙基淀粉的共同特性。

Distarch phosphate （1412）,hydroxypropyl starch （1440）,and hydroxypropyl distarch phosphate （1442） were synthesized from waxy starch （WS）,respectively.Their properties such as viscosity,shear resistance,acid resistance,transparency,and freeze-thaw stability were characterized and compared to investigate the effect of modifications.The results indicate that：（1） Crosslinking leaded to lower gelatinization temperature and increase the peak viscosity.Although both of its transparency and freeze-thaw stability were much improved,but its hot paste stability and acid resistance became worse; （2） hydroxypropyl starch possessed a higher gelatinization temperature and lower peak viscosity.Although its shear resistance and acid resistance were much improved,but its transparency became worse and its freeze-thaw stability remains unchanged; （3） hydroxypropyl distarch phosphate had combined characters of distarch phosphate and hydroxypropyl starch.