Extraction of carotenoids from tomato pomace using deep eutectic solvents composed of short and medium-chain fatty acids and menthol

Tomatoes are rich in carotenoids, which remain in significant quantities in tomato pomace and can be sustainably extracted. This study aimed to develop a method for extracting carotenoids from tomato pomace using deep eutectic solvents composed of menthol and fatty acids (butyric, hexanoic, caprylic, lauric, and palmitic), as an alternative to toxic and polluting organic solvents. Preliminary screening identified the most effective deep eutectic solvent, while design of experiment and a kinetic study optimized the extraction process. Under optimal conditions, the DES extracted approximately 300 μg/g of carotenoids on a dry weight basis. HPLC analysis of the extract quantified 24 μg/g ± 5 of β-carotene and 52 μg/g ± 2 of lycopene. The menthol-butyric acid DES outperformed conventional organic solvents, emphasizing its sustainability and efficiency.