冻藏对小麦淀粉理化性质及热力学特性的影响

研究了冻藏对小麦淀粉颗粒表面形态、理化性质、热力学性质及凝沉特性的影响。通过扫描电镜(SEM)检测冻藏小麦淀粉颗粒,发现部分淀粉颗粒表面有破损;对冻藏后的小麦淀粉溶解度、粘度、膨润力、蓝值等进行测定,结果显示冻藏后淀粉溶解度和粘度分别增大了48.6%、43.2%;膨润力、蓝值分别降低8.41%、28.5%;采用示差量热扫描(DSC)测定冻藏小麦淀粉热力学性质变化,发现冻藏小麦淀粉糊化热焓降低了47.3%,糊化温度起止范围降低了10.60%;凝沉值降低了47.2%。研究表明冻藏后的小麦淀粉颗粒形态,理化性质、热力学性质均发生了明显改变。 

Effect of frozen storage on the physicochemical properties and thermodynamic properties of wheat starch

The morphology, physicochemical properties, thermodynamic properties and retrogradation characteristics of wheat starch were studied by frozen storage. Frozen wheat starch granules was detected by scanning electron microscopy ( SEM) , which found that some of the starch granule surface damage.The frozen wheat starch solubility, viscosity, swelling power, blue values were measured, and the results showed that frozen storage starch solubility and viscosity increased 48.6% and 43.2%, and swelling power, blue values were decreased 8.41%, 28.5%. The thermodynamic properties of frozen wheat starch were measured by differential scanning calorimetry ( DSC) , and found the enthalpy and the temperature range of gelatinization decreased by47.3% and 10.60%.The retrogradation value decreased by 47.2%. The results showed that morphology, physicochemical properties, thermodynamic properties were changed significantly for frozen wheat starch.