Chapter 21 - Vegetable Oils

Vegetable oils under a protected designation of origin (PDO) are highly susceptible to fraud. Therefore, in order to protect the producers, inform the consumers and contribute to the maintenance of a high quality within the sector, huge efforts have been made to discover analytical strategies to verify the authenticity of PDO vegetable oils. Due to its high use and appreciation by consumers, olive oil is the vegetable oil having the highest number of PDOs; however, PGIs have been authorized for other types of vegetable oils as well, such as pumpkin seed oil. Several targeted and semi-targeted analytical strategies have been proposed in the literature to verify olive oil PDO: fatty acid composition, triacylglycerol profile, volatile compounds and the determination of trace elements and stable isotopes, among others. However, the state-of-the-art techniques in food authentication are based on food fingerprinting strategies, combined with chemometrics. Fingerprinting models might be developed after a targeted or semi-targeted analysis, but also directly with the analytical signals obtained from certain equipment, such as a chromatogram, a mass or a near-infrared spectrum. This chapter provides an overview of the strategies for authentication of vegetable oils as well as a comparison of their advantages and disadvantages.