电导率法快速检测煎炸油极性组分含量的研究

Rapid Detection of the Polar Component Content of Frying Oil by Conductivity Method

以大豆油、棕榈油和米糠油为煎炸用油,在(190±5)℃的煎炸温度下进行32 h连续煎炸油条试验,通过对不同煎炸时间所取煎炸油样极性组分含量和电导率值的测定以及两者之间对应关系的对比分析,研究电导率法在快速检测煎炸油中极性组分含量方面的应用。结果表明,大豆油、棕榈油和米糠油的极性组分含量均随煎炸时间的延长而增大;电导率值随煎炸时间的延长呈波动变化,整体呈增大趋势;极性组分含量和电导率值之间无显著线性关系。因此,电导率法可用于油脂是否经过煎炸的快速鉴别及煎炸程度的初步鉴别,但能否应用于煎炸油中极性组分含量的快速测定或应用电导率值表示极性组分含量还需进一步深入研究,同时应对电导率值测定方法进行完善和规范。

The continuous frying experiment was proceeded at the frying temperature of （ 190 ± 5 ） ℃ for 32 h. Soybean oil, palm oil and rice bran oil were utilized to be the raw materials for frying medium and deep - fried dough sticks. The polar component content and conductivity of frying oil sample were monitored to research the application of conductivity on the rapid detection of frying oil＇s polar component content. The results showed that the polar component content of those three kinds of frying oils all increased with gradually prolonged frying time. The conductivity of these frying oils fluctuated with overall trend to increase. These was no significant linear relationship between the polar component content and conductivity. Therefore, the conductivity method could be used to rapidly distinguish frying oil and preliminary distinguish the fried degree, but for rapid detection of the polar component content of frying oil, further research was necessary.