冷榨亚麻籽油的流变特性研究

通过低温压榨亚麻籽获得冷榨亚麻籽油（cold—pressed flaxseed oil，CFO），并分析其主要理化指标，着重研究CFO的静态、动态流变特性，同时分别采用Casson、Herschel-Bulkley和Bingham模型对其流体行为进行拟合，并采用Arrhenius方程分析其粘度热动力学参数。研究结果表明：在剪切速率为0．1～200s“下，CFO由非牛顿流体逐渐转化为牛顿流体；当剪切速率大于10s^-1时，CFO呈牛顿流体；同时分析得出CFO的粘度活化能为3095．4cal／mol；CFO的粘度、剪切应力、损耗模量、塑性稠度系数、高剪切极限粘度和稠度系数随着温度升高而降低，但是温度变化对CFO的贮能模量影响不显著；另外通过比较3个流变模型得出Bingham模型适用于CFO。

Rheological properties of cold - pressed flaxseed oil

The cold - pressed flaxseed oil （CFO） was obtained from the flaxseed by cold - pressing. The physicochemical index of CFO was analyzed, and the static and dynamic rheologieal properties were investigated. Also the Casson, Herschel - Bulkley and Bingham models were used to describe the rheological behavior of CFO, and thermodynamic parameters were derived from the Arrhenius equation. The results showed that CFO behaved gradually fi-om non - Newtonian fluid to Newtonian fluid within the shear rates of 200s^-1. When the shear rates were greater than 10s-I, CFO indicated a Newtonian behavior. Moreover, the CFO＇s energy of activation for viscosity was 3 095.4 cal/mol. Furthermore, Viscosities, shear rate, loss modulus, the plastic consistency coefficient, higher shear limiting viscosity and consistency coefficient of CFO decreased with the increasing temperature, but the storage modulus of CFO had no significant change by temperature. The result also showed that the Bingham model was suitable to describe the rheological behavior of CFO.