UV-Vis Spectroscopic Characterization and Wavelength Analysis of Binary Edible Oil Mixtures for Adulteration Detection

Abstract

This study investigates the effect of mixing different edible oils on their spectroscopic properties, using UV-visible spectroscopy as a rapid and effective analytical tool. We conducted spectral analysis on various binary oil mixtures, specifically mustard oil mixed with argemone, mineral, and castor oils, as well as coconut oil mixed with mineral and palm oils. These findings consistently demonstrate that mixing oils leads to noticeable changes in absorbance values, while the characteristic wavelength range generally remains within the ultraviolet region (200–400 nm). A key observation across all mixtures was a reduction in absorbance with an increasing proportion of the adulterant oil. This trend is primarily attributed to a dilution or alteration of the inherent chromophoric compounds responsible for light absorption in the primary oils. These spectral shifts are fundamentally driven by variations in the chemical compositions of the individual oils, including their pigment content, fatty acid profiles and the presence of oxidation products. This research highlights the sensitivity and effectiveness of UV-vis spectroscopy for detecting oil adulteration and assessing purity. This technique not only identifies compositional changes resulting from mixing oils but also offers insights into potential quality degradation in edible oils. Consequently, these findings underscore the significant potential of UV-visible spectroscopy for routine food quality control and adulteration detection applications in the edible oil industry.