Novel Improved Sensitivity Planar Microwave Probe for Adulteration Detection in Edible Oils

Novel design of the complementary split ring resonator (CSRR) loaded planar microwave probe with improved sensitivity is proposed for liquid adulteration detection. As compared to the conventional planar resonant sensors, the proposed single-port structure is quite advantageous for detecting adulteration in edible fluids since it can directly be immersed inside the liquid specimen. The flared microstrip line of the proposed probe facilitates the etching of two CSRRs on the top side at the electric field maxima resulting into the compact design with improved sensitivity. The parameters of the probe are optimized using the CST-MWS, and its prototype is fabricated, which possesses the ability to easily distinguish two materials having close dielectrics values. Finally, the proposed probe is successfully employed for adulteration testing of various edible oils where the presence of common adulterants such as mineral oil inside high-quality olive oil and mustard oils can be clearly detected.