Estimation of dielectric constant of oil solution in the quality analysis of heated vegetable oil

Suitability of dielectric constant was measured using designed layered capacitive cell in the quality analysis of palm, peanut and corn oil after three cycles of heating up to 190 °C of temperature. Dielectric constant value (at 2 MHz frequency) increases with three cycles of heating was experiential and correlated (R2 > 0.973) with physical properties. Measured density, refractive index and dielectric constant (εr) were used to calculate specific refractive index and polarization using Debye's equation. To increase the mobility of polar compounds, 25% of CCl4 was added to 75% of oil; its capacitance and dielectric constant were experiential at different temperature (40 to 65 °C). Physical properties like relative viscosity, refractive index and electric dipole moment of oil solution were used to estimate; apparent molecular relaxation time, polarization of oil solution using Wyman's analyses. Variation of εr was fitted with empirical equations; the constants and regression coefficients for different times heated oil solution was determined. The dependency parameter R2 ranges from 0.956 to 0.999. The designed capacitor was used to measure dielectric constant of oil solution which would be a non-invasive and resolute property to study the storage life of oil in food industry.