削皮、水洗和干燥温度对木薯淀粉纯度和淀粉糊化粘度的影响

木薯在热带地区是碳水化合物的主要来源。木薯淀粉的品质受许多因素的影响。本项研究着重探讨淀粉提取过程中，削皮、水洗、干燥温度对淀粉纯度、白度和淀粉糊化粘度的影响。结果表明，未削皮的淀粉样品色发灰，但具有比削皮处理高的峰值粘度、95℃最后粘度、50℃时粘度、峰值降和持久性。增加水洗次数，不但能增加淀粉纯度，还可提高淀粉高峰值粘度、95℃最后粘度、50℃时粘度、持久性和糊化温度。不同干燥温度对淀粉白度无影响，但淀粉纯度随干燥温度的提高而稍稍增加。通常高的干燥温度有高的峰值粘度、95℃最后粘度、峰值降、50℃时粘度和持久性。

The effect of peeling,washing and drying on starch purity and starch paste viscosity

Cassava root is used for carbohydrate source in tropical region.Quality of cassava starch is variable and affected by many factors.An attempt was made to evaluate the effect of peeling,washing and drying on starch purity and starch paste viscosity.Paste viscosity were based on results of Rapid Visco Analysis (RVA).The results of this study revealed that:peeling,washing and drying temperature significantly affected cassava starch purity and starch paste viscosity.The starch from unpeeling root had a dullness color,but had higher peak viscosity,trough,final viscosity,breakdown and setback than that of starch from peeling root.More washing not only increased starch purity,but also improved starch past characteristics,such as peak viscosity,trough,final viscosity,setback and pasting temperature.Different drying temperature had no effect on starch whiteness.Starch purity had a little increase with drying temperature increasing.In general trend,starch dried at higher temperature had higher peak viscosity, trough, breakdown, final viscosity and higher setback.