Detecting olive oil counterfeiting by dilution with rapse and sunflower oils according to the triacyl glyceride profile using the method of gas chromatography

Olive oil is a valuable food product, a source of monounsaturated fatty acids, antioxidants, including polyphenolic nature, as well as terpenes and phytosterols. The high cost, along with the demand for special dietary properties, makes olive oils an attractive target for counterfeiting, most often done by diluting olive oil with cheaper sunflower and rapeseed oils. Considering that traditional indicators of identification of vegetable oils do not allow to detect such falsification; it is relevant to search for new objective indicators and methods for identifying olive oils. The purpose of the research is to justify the use of triacylglyceride profile for identification and detection of falsification of olive oils. The objectives of the research include the selection and adaptation of an effective and affordable method for determining the triacylglyceride profile; identification of reliable markers of identification and falsification of olive oils, carried out by diluting them with sunflower or rapeseed oils; establishing dependencies that allow determining the amount of sunflower or rapeseed oil mixed with olive oil. Gas chromatography with a flame ionization detector has been used as the main research method. Based on the studies carried out, the method of gas chromatography with a flame initiation detector has been adapted for the analysis of the triacylglyceride profile of olive, sunflower and rapeseed oils, as well as their mixtures. Markers have been established that make it possible to unambiguously identify the falsification of olive oil by diluting it with sunflower or rapeseed oil. Calibration graphs and dependencies are proposed that allow you to set the amount of sunflower or rapeseed oil in a mixture with olive oil.

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