改性羧甲基淀粉糊液的流变性能  

The rheological properties of modified carboxymethyl starch pastes

作　　者：薛丹[1,2] 吕伟[3] 刘祥[2] 李晗[2] 

机构地区：[1]西北工业大学理学院,陕西西安710072 [2]西安石油大学化学化工学院,陕西西安710065 [3]长庆油田公司油气工艺研究院,陕西西安710018

出　　处：《食品与发酵工业》2016年第4期75-79,共5页Food and Fermentation Industries

基　　金：陕西省教育厅专项科研计划项目(14JK1569)

摘　　要：对复合改性的高黏度羧甲基淀粉（composite modified starch,CM-St）糊液的稳态剪切及小幅振荡动态剪切下流变性能进行了研究。通过对实验数据的拟合,确定以Ostwald-de Waele经验公式（幂率模型）作为描述CM-St糊液的本构方程。高黏度CM-St糊液具有较强的触变性,且随质量分数的增加而增强;糊液表现出假塑性流体特征,流性指数n值随糊液质量分数的增大而减小,却随温度升高而增大;稠度系数K值及100 s^-1下的表观黏度ηa,100值均随糊液质量分数增大而大幅度增大,随温度（20-60℃）的增加而有小幅减小;CM-St糊液活化能Ea随质量分数的增加而减小,而常数A呈增大趋势;CM-St糊液表现出较强的黏弹性,且其弹性大于黏性,其糊液储能模量及损耗模量均随质量分数的增大而增大。The rheological properties of the CM-St paste with high viscosity were studied by means of steady shear measurement（ viscometry） and in small amplitude oscillatory shear（ viscoelasticity）. The experimental data were fitted to the well-known Ostwald-de Waele empirical formula（ power law model） which was used for constitutive equation of the CM-St paste with high viscosity. The results indicated that the thixotropy of high viscosity CM-St became more and more obvious as its concentration increased. The characteristics of Pseudo plastic fluid,the flow behavior index（ n） and activation energy（ Ea） decreased with the increasing of CM-St concentration,the apparent viscosity（ ηa,100）,consistency index（ K）,and pre-exponential factor（ A） rapidly increased with the increasing of CM-St content,whereas the apparent viscosity（ ηa,100） and consistency index（ K） decreased with the increasing of temperature ranged from 20 ℃ to 60 ℃. The CM-St has good viscoelastic properties and elasticity is stronger than its viscosity.

关 键 词：复合变性淀粉(composite modified starch CM-St) 羧甲基淀粉(carboxymethyl starch CMS) 流变性能 假塑性流体 

分 类 号：TS231[轻工技术与工程—粮食、油脂及植物蛋白工程]