Understanding the variations in dielectric properties of mustard (Brassica nigra L.) and argemone (Argemone mexicana) oil blends at different temperatures

Mustard oil is the most commonly adulter-ated edible oil, invariably with argemone oil. This study was aimed to develop a parallel plate capacitive sensor for measurement of dielectric properties of pure mustard oil, pure argemone oil and their blends (25, 50 and 75%) at five levels of varying temperature (10 to 50 degrees C). The effect of blend ratio and temperature on the selected dielectric proper-ties of oil & mdash;capacitance (C), dielectric loss tangent (tan delta), dielectric constant ( ??' ), dielectric loss factor ( ??' ) and electri-cal conductivity (sigma) were investigated. It was observed that composition of the individual oils in terms of moisture and fatty acids influenced the physical and dielectric properties. The sensor was used to relate the dielectric properties of oil samples with blend ratio and temperature by means of sta-tistically significant (p < 0.05) and robust (R-2 > 0.8) multiple linear regression model. The effect of temperature on C and ??' was negative, while it was otherwise for tan delta, ??'' and sigma. Increase in argemone oil content in the blends, increased the dielectric measures due to the associated changes in the physical and chemical properties. The capacitive sensor could distinctly identify mustard oil, argemone oil and its blends on the basis of dielectric properties

Automated summary

A parallel plate capacitive sensor was developed to measure the dielectric properties of mustard oil, argemone oil, and their blends. The study found that blend ratio, temperature, moisture, and fatty acid composition of the oils influenced their dielectric properties.