Authenticity of olive oil: Mapping and comparing official methods and promising alternatives

Abstract Trade standards are continuously updated to give plausible solutions to situations created by fraudsters who apply the most sophisticated procedures to their objectives of olive oil adulteration. Clustered inside targeted and profiling approaches, methods based on spectroscopic, isotopic and chromatographic techniques are reviewed. Chromatographic methods, most of them being official methods, compete with newer methods based on spectroscopic, isotopic and trace element techniques for ensuring that the pace of research in the detection of malpractices is rapid enough. The speed of the analyses, the need of statistical interpretation of the results, the quality parameters of the methods, limit of detection of the adulterants, and the applicability range among others are on the basis for the absolute and comparative analyses of the most known methods, which results are unpacked in the paper. The new frontiers of research in the field of olive oil authenticity are also dissected together with the challenges for the near future. The extensive and deep analysis of the methods for quantifying the chemical compounds responsible for olive oil authenticity will contribute to a better comprehension of the complex analytical world of olive oil for the analyst working with this food product for the first time, as well as for experienced professionals.

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