Use of fluorescence spectroscopy in the determination of contamination and oxidative processes in edible vegetable oils

Abstract

The world consumption of vegetable oils in food products was over 104 million tons in the last year. Edible vegetable oils have a high incidence of contamination by Polycyclic Aromatic Hydrocarbons (PAHs) and mycotoxins, indicated as possible responsible for the development of neoplasias. In addition, they are highly susceptible to lipid oxidation, complex reactions that result in the production of toxic substances, with serious nutritional consequences to their consumers. In this context, strict quality control of these products is of utmost importance, with the continuous improvement of the analytical techniques used and the development of new and efficient methods capable of complementing or replacing them. Considering this scenario, the present research project proposes the use of fluorescence spectroscopy for the detection of contaminants (PAHs, microorganisms and aflatoxins) and determination of lipid oxidation status. The proposed method consists in the extensive study of the fluorescence spectra of vegetable oils, relating changes in emission intensity and wavelength with the presence of these contaminants and with the advancement of oxidation reactions, in addition to determining the generation of singlet oxygen and its importance in oxidative processes. The advantages of the fluorescence-based methods are the high sensitivity, fast results and the possibility of direct analysis of the sample, avoiding expensive preparation procedures, and portable equipment for in situ analysis. The fulfillment of the proposed objectives will result in a method capable of determining quality indicators of vegetable oils, being able to be applied in the food industry and institutions responsible for food quality control. (AU)