中文摘要：

采用搅拌球磨机对木薯淀粉进行机械活化，分别研究了机械活化对木薯淀粉糊透明度的影响和淀粉糊储藏过程中机械活化时间与淀粉糊浓度对其透明度的影响．并通过X射线衍射研究了机械活化对木薯淀粉结晶结构的影响．结果表明，机械活化作用时间越长，淀粉糊透明度越高．这是由于机械活化使木薯淀粉颗粒结晶结构受到破坏，结晶程度降低，最终由多晶态转变成非晶态．淀粉糊储藏过程（储藏温度4℃）中发生老化是引起透明度变化的主要因素．机械活化时间为2h的样品易老化，淀粉糊透明度迅速下降，而机械活化时间达3h后木薯淀粉则过度降解，淀粉糊透明度下降变慢．同时还发现，机械活化淀粉糊储藏过程其透明度的变化与糊浓度密切相关，当浓度在10g/L左右时，机械活化淀粉糊不易老化，而浓度提高到50g／L后，则老化加速，淀粉糊透明度迅速下降．

英文摘要：

Cassava starch was mechanically activated by a stirring-type ball mill, the effect of mechanical activation on the transparency of cassava starch paste and the variation of the transparency with different mechanical activation times and paste concentrations in the process of storage were investigated respectively. Moreover, the variation of cassava starch crystalline structure in the process with mechanical activation was studied by employing an X-ray diffractometer. The results indicated that the transparency increased with increasing of mechanical activation time. The increased transparency is due to that the crystalline structure of cassava starch could be destroyed by mechanical activation and the crystallinity decreased fi＇om polycrystalline to amorphous state. The main factor of transparency change was the retrogradation of starch paste during storage （storage temperature 4 ℃）, it was proved to be in favor of the retrogradation of starch paste, and the transparency decreased abruptly when mechanical activation time was 2 h, however, once above 3 h, cassava starch would be overly degraded and the transparency decreased slowly. It was also found that the extent of transparency change was related to paste concentration during storage of mechanical activated starch paste, when starch paste concentration was about 10 g/L, retrogradation would be difficult, but the retrogradation was enhanced and the transparency decreased abruptly at the paste concentration up to 50 g/L.