花生油高频剪切黏度超声检测

Shear viscosity testing of peanut oil by ultrasound

为对多次高温加热食用油品质进行评价,以反复煎炸花生油为研究对象,基于超声水平剪切波(SH波)在固体/黏弹性液体界面的复反射系数与液体黏弹性模量、黏度系数等关系模型,以固体/空气界面为参考,采用固/气、固/液界面回波对比方法,测量了不同劣化状态花生油在室温时的剪切黏度,并与流变仪测试结果进行比较。结果表明,超声SH波与流变仪均很好地反映了样品黏度随加热次数的变化关系。研究证明超声方法在线评价油品劣化状态具有可行性。

The repeatedly fried peanut oil was taken as the research object to evaluate the quality of edible oil heated for many times at high temperature. Based on the relationships between complex reflection coefficient of SH wave at solid/viscoelastic liquid interface and viscoelastic modulus and viscosity coefficient of liquid,and the reference of solid/air interface,the shear viscosity of peanut oil with different degree of deterioration at room temperature were measured by using solid/air and solid/liquid interface echo contrast method,and compared with those measured by the rheometer. The results showed that both the ultrasonic SH wave and the rheometer could well reveal the relation between viscosity and heating times.The study proved that on-line evaluation of oil deterioration by ultrasound method was feasible.