Probe Based SIW Microwave Sensor for Detection of Adulteration in Mustard Oil

A low-cost Substrate Integrated Waveguide (SIW) based sensor is proposed in the paper for detection of adulteration of edible oil especially mustard oil. The adulteration in mustard oil is done in variety of ways by adding low cost oil in different percentage of volume by volume. These adulterations produce multiple health hazards to the human mankind as the edible is used in daily consumption at Indian homes. The proposed sensor is based on probe techniques, where the detection of dielectric constant change is measured by dipping the one end of sensor in the liquid and may be reutilized after cleaning. The change in the dielectric constant of the liquid is expected when there is mixing of any kind oil to the pure mustard oil. This change in dielectric constant produces shift in the S-parameter which is measured through the VNA. The paper proposed a SIW based sensor with concentric rings at the end of the probe to make it sensitive to the small change if dielectric constant of the edible oil changes. The resonance of the probe is fixed to the X-band to make it cost effective due to low cost dielectric material used for fabrication.