高温加热对玉米淀粉糊化特性的影响

Effect of high-temperature processing on gelatinization property of corn starch

针对高温加热对玉米淀粉的影响进行分析。采用“120℃加热1—10h”和“120℃～200℃加热1h”两种方案对原淀粉进行处理，并使用偏光显微镜和Brabender黏度仪测试淀粉的颗粒形貌、偏光十字和糊化曲线。结果表明：淀粉的颗粒形貌无明显变化，只是在120℃下加热10h或200℃加热1h后，淀粉颗粒的棱角受到一定程度的破坏，变得比较圆滑；在120℃下加热8～10h或在180℃～200℃下加热1h后，淀粉颗粒的偏光十字逐渐模糊，少数淀粉颗粒发生了非晶化现象；随着加热时间的延长或温度的提高，糊化温度先增加后降低，而峰值黏度、热糊黏度和最终黏度都显著降低。

The effect of high-temperature processing on the property of corn starch is analyzed by two programs on native starch processing, one is heated at 120℃ for one to ten hours and another is heated at different temperatures from 120℃ to 200℃ for one hour. The particle morphology and crystal structure and the gelatinization property of the starch are characterized by using polarized light microscope and Brabender viscometer. The result shows that the starch particle shape is not significantly changed, and when heated at 120℃ or 200℃ for one hour the edge of starch particle is destroyed to some extent and became relatively smooth when heated at 120℃ for eight to ten hours and heated at 200℃ for one hour, the polarization cross is gradually blurred. Some of starch particles became mone-crystalized. And the gelatinization temperature increased first and then decreased with the heating duration or temperature increasing. The peak viscosity, hot paste viscosity and final viscosity significantly decreased.