Evaluation of UV-Irradiation Degradation of Vegetable Oil Using Optical Absortion Spectra

Soybean oil (SO) contains significant amounts of linoleic acid and oleic acid, contributing to its fatty acids profile. The degradation of vegetable oils occurs through oxidation, hydrolysis, and polymerization, affecting their chemical and sensory characteristics. Factors like heat, radiation, and oxygen accelerate this process. Assessing the impact of UV radiation on vegetable oils helps to stablish their storage and preservation methods. Therefore, in this study, the characterization of the degradation process is performed using Fourier Transform Infrared (FTIR) spectroscopy of UV-irradiated SO with UVA and UVB wavelengths. Spectral analysis is conducted to identify degradation products such as oxidation by-products and changes in characteristic functional groups of SO, utilizing the difference of normalized spectra and its first derivative to evaluate the increase or decrease in the absorption spectrum. The spectrophotometric study of carotenoids and chlorophyll reveals changes in chemical composition, oxidative status, and pigment degradation caused by UV exposure. These findings provide insights into the impact of UV radiation on vegetable oils, guiding the development of strategies to preserve their quality and nutritional value.