Tomato Pomace as a Valuable Resource: Characterization of Sunflower and Rapeseed Oil Extracts from Ox Heart Tomato (Lycopersicon esculentum)

This study investigates the potential use of tomato pomace, a by-product of tomato pulp and seeds, as a functional additive in sunflower and rapeseed oils. The aim was twofold: to improve the oxidative stability of the oils and to enhance their nutritional value for potential food applications. Extractions were performed using different concentrations of tomato pomace (2%, 4%, and 6%) at varying temperatures (40°, 50°, and 60 °C) and stirring speeds (150, 200, and 250 rpm). The resulting samples were evaluated for antioxidant activity, peroxide value, and color characteristics. To further assess oil composition and stability, advanced analytical techniques were employed. Fourier-transform infrared spectroscopy (FTIR) identified key functional groups and structural modifications, while differential scanning calorimetry (DSC) revealed differences in thermal stability across the samples. High-performance liquid chromatography (HPLC), optimized for compound separation and detection, identified several carotenoids, including canthaxanthin, lutein, lycopene, and alpha carotene. Notable differences between extracts made with sunflower versus rapeseed oil were observed, reflecting variations in chemical composition, extraction efficiency, and oil-pomace interactions. In conclusion, the incorporation of tomato pomace into vegetable oils not only enhances oxidative and thermal stability but also enriches the oils with valuable bioactive compounds, supporting their potential use in functional food formulations.