稻米淀粉的糊化动力学研究

Study on the Gelatinization Kinetics of Rice Starch

采用一级反应模型对不同类型稻米淀粉的糊化特性和糊化动力学进行了研究 ,结果表明 :不同类型稻米淀粉的糊化特性有较大差异。淀粉的糊化能耗主要用于淀粉晶体的熔解、颗粒的膨胀和直链淀粉分子从淀粉颗粒中的脱离。其中以晶体崩解速度最大 ,所需能耗最小 ;其次为颗粒膨胀能 ;直链淀粉溶出的速度最小 ,所需能耗最大。不同来源淀粉的膨胀速度和直链淀粉溶解速度、糊化能及其分配也有所差异 ,以籼稻的润胀能较小 ,其次依次为粳稻和糯稻 ;籼稻直链淀粉脱离淀粉颗粒 (淀粉糊上清液BV值 )所需能耗最大 ,其次为粳稻。 3种稻米淀粉的酶解能耗差异不大 。

The gelatinization kinetics of starch from different rice varieties under excessive water was studied according to the first grade reaction model. Ratio constant and gelatinating energy were decided respectively, based on the swelling power, blow value and enzyme hydrolyzing degree. Results indicated that the starch crystal was melted, starch granule was swollen, and the amylose was departed from the starch granule under thermo energy . The crystal melting needed lower energy than that of swelling power and the solution of amylose. Among three types of rice, indica rice deeded lower energy to swell, its amylose needed the highest energy to depart, and the hydrolyzing energy it needed was slightly lower than that of japonica rice and glutinous rice.