In this study,pasting and rheological properties of native potato starch,potato starch phosphate ester and cationic potato starch were determined in the respective presence and simultaneous absence of guar gum and xanthan gum.The results indicated that the presence of guar gum enhanced the peak viscosity and pasting temperature of all three kinds of potato starches and deteriorated the thermal stability of starch pastes.The peak viscosities of native potato starch and potato starch phosphate ester rose and the thermal stability and pasting temperature declined due to the presence of xanthan gum,compared to opposite changes observed for cationic potato starch.Dynamic rheological studies revealed that the addition of xanthan gum considerably raised the G＇ and G＇＇ values and declined the tanδvalue of each kind of potato starch.The dynamic rheological properties of cationic potato starch were affected most obviously.By contrast,guar gum had no obvious effect on the dynamic rheological properties of all three kinds of potato starches.In static rheological studies,we found that starch pastes remained pseudo-plastic fluids despite the presence of either guar gum or xanthan gum,with shorted lag ring area and improved stability.Native potato starch and potato starch phosphate ester were more obviously affected than cationic potato starch.Moreover,xanthan gum had more obvious effect than guar gum.Further,our studies demonstrated that gum-starch interactions play a vital role in pasting and rheological properties of gum-starch complexes.%研究瓜尔胶和黄原胶对马铃薯淀粉、马铃薯磷酸酯淀粉和马铃薯阳离子淀粉糊化和流变性质的影响。糊化性质实验表明瓜尔胶增加了3种淀粉的峰值黏度和成糊温度,降低了淀粉糊的热稳定性。黄原胶降低了马铃薯淀粉和马铃薯磷酸酯淀粉的峰值黏度并提高了糊的热稳定性和成糊温度,但对马铃薯阳离子淀粉起相反作用。动态流变实验表明加入黄原胶显著提高了3种淀粉的G′、G′′值,降低了损耗角正切值tanδ,黄原胶对马铃薯阳离子淀粉动态流变学性质的影响最大,瓜尔胶对3种淀粉的动态流变学性质的影响不显著。静态流变实验表明加入瓜尔胶和黄原胶后的淀粉糊仍为假塑性流体,滞后环面积减少,稳定性提高,两种胶对马铃薯淀粉和马铃薯磷酸酯淀粉的作用比对马铃薯阳离子淀粉作用明显,并且黄原胶比瓜尔胶对淀粉作用更为显著。研究发现胶体与淀粉之间的电荷相互作用对复配体系的糊化性质和流变学性质起重要的作用。
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