Photoionization Sensor for VOC Detection in Tomato Seed Oil

In the evaluation processes of vegetable oils, special attention is paid to the distribution of fatty acids, given its relevance to organoleptic and functional properties. Changes in the amount of some specific molecules prove decisive both in verifying the authenticity of the product and in assessing its potential health benefits. In particular, volatile organic compounds (VOCs), which originate from the degradation of fatty acids, have proven to be effective tools for detecting possible fraud or alterations. These substances not only contribute to the aroma and taste profile of oil, but also act as a kind of chemical signature, capable of returning detailed information about its composition. The present study proposes an innovative method for the analysis of tomato seed oil (TSO), based on the use of a photoionization detector (PID) coupled with a thin layer of 5A zeolite, the latter used to promote the selective adsorption of specific compounds. The analysis is done by thermal desorption at 100° C. The PID-zeolite system was successfully applied to selectively identify palmitic acid in a mixture of pentane and TSO, providing a reliable indication of the authenticity of the oil and the possible presence of adulteration.