Detection of Fatty Acids in Tomato Seeds Oil Through a Zeolite-PID System

Seed oils are vegetable oils extracted from the seeds of various plants. These oils can be obtained from waste processing, such as fruit and vegetable seeds, which would otherwise be discarded thus helping to reduce waste and enhances the value of food industry by-products. Tomato seeds oil (TSO) is characterized by high concentration of volatile organic compounds (VOCs), which includes fatty acids, vitamins, antioxidants and other compounds resulting in beneficial effect on human health. VOCs levels can be used as fingerprint of the TSO. Hereafter, a VOC sensor for the analysis of tomato seeds oil was developed. The VOCs analysis allows quality assessment through the monitoring of specific fatty acids contained in the sample. A sensor based on photoionization (PID) coupled with a thin zeolite layer was used for the adsorption/desorption of specific molecules trapped within the porous framework. The latter was obtained by thermal desorption analysis. Results evidenced the sensor capability to detect and discriminate between oleic acid and other VOCs inside the oil samples, even at low concentration, based on their dimension and ionization energy.