The effect of microwave heating was studied in six varieties of edible oil. Variations in physicochemical properties were
observed and compared with the data obtained by hot plate heating. Fourier-transform infrared spectra of the oils showed substantial
variations after both types of heating in the region of hydrogen’s stretching (C–H) vibration, region of double bond’s stretching
(C=O), and fingerprint region. The visible spectra of mustard and olive oil showed the reduction in carotenoid, flavonoid,
and chlorophyll pigments after heating. The oil samples were discriminated as saturated, monounsaturated, and polyunsaturated
fats using chemometric techniques on physical and spectroscopic measurements.