Research: Green extraction method for tomato peel nutrients

Tomato processing creates a large amount of peel waste, even though these peels naturally contain high levels of lycopene, beta-carotene and polyphenols. These compounds are valuable because they provide colour, flavour and antioxidant activity. A recent study tested a cleaner way to recover them so they can be reused in Mediterranean food products.

The researchers worked with a plant-based deep eutectic solvent made from menthol and camphor. This type of solvent is considered safer and more environmentally friendly than traditional chemical solvents. To help the solvent reach the nutrients inside the peel cells, the team first applied a short pulsed electric field treatment, which gently opens the cell structure. They then used ultrasound, which improves the mass transfer and helps release the compounds into the liquid.

This combined method allowed the recovery of high levels of lycopene, beta-carotene and polyphenols, especially under mild and short treatment conditions. These conditions were important because longer and stronger treatments can cause nutrient loss. With the optimised settings, the extracts showed good antioxidant activity and stable colour, which makes them suitable for use in sauces, juices, fruit leathers, bars and powdered mixes.

Why this matters

• It turns tomato peel by-products into valuable natural ingredients.
• It offers a cleaner and lower impact alternative to conventional solvent extraction.
• It provides industry with a practical way to increase the nutritional and functional value of tomato-based products.
• It supports Mediterranean dietary preferences by focusing on natural pigments and antioxidants.

This research is one of the scientific outputs of the PRIMA-funded FunTomP project, which develops healthier and more sustainable Mediterranean foods through innovative processing (see www.funtomp.com).