In a significant move to combat carbon emissions and address the high-flying challenge of aviation sustainability, European scientists have initiated a project focused on transforming the discarded remains of tomatoes into environmentally friendly jet fuel, reports Interesting Engineering.
The ambitious, four-year research effort, which has the backing of the European Union and is being coordinated by Austria’s Graz University of Technology (TU Graz), is reportedly striving to create a processing system that leaves nothing behind and produces no net climate-warming emissions.
Named “ToFuel,” the innovative project is dedicated to converting the leftovers from tomato processing—known as tomato pomace—into Sustainable Aviation Fuel (SAF). As a bonus, the process will also generate valuable side products, including materials for fertilizer, animal feed, and specialized oil supplements.
“Estimates suggest that the amount of tomato waste produced across the European Union could cover about three percent of the sustainable aviation fuels needed in Europe by 2030,” explained project manager and TU Graz professor, Dr. Marlene Kienberger.
The research team believes this innovative method can significantly aid Europe’s drive to reduce aircraft pollution while simultaneously giving agricultural waste, which is currently thrown away or burned, a new economic purpose.
Tomatoes are globally the second-most-eaten vegetable. Europe alone harvests approximately 17 million tons each year, creating massive amounts of unused plant material.
This waste includes leaves, stems, skins, seeds, and fruits that are unripe or damaged. Although usually categorized as worthless, these residues are full of energy-rich compounds that can be successfully converted into jet fuel.
To accomplish this conversion, the scientists are investigating two advanced preparation techniques. The first involves extrusion, where the tomato material is heated and pressurized, followed by a rapid drop in pressure. This action breaks open the plant cells, preparing the material for fermentation, where tiny organisms turn the compounds into thick, oil-like lipids suitable for making fuel.
The second method uses hydrothermal liquefaction, which treats wet plant matter with high heat and pressure to create crude bio-oil and a solid material called biochar. The resulting bio-oil then goes through a cleaning process to remove nitrogen-containing substances that would otherwise hinder fuel creation.
Scientists from TU Graz, the University of Zagreb in Croatia, and Portugal’s national energy laboratory (LNEG) are collaborating on the essential purification and separation steps.
The cleaned lipids and bio-oil are then sent to the Technical University of Leoben in Austria to be refined into a final fuel that meets international quality standards for Sustainable Aviation Fuel. This is done using the established HEFA (Hydrogenated Esters and Fatty Acids) process, which is a proven way to make jet fuel from fats and oils sourced from vegetables, animals, or recycled materials.
Leading the ToFuel project is Dr. Marlene Kienberger from the Institute of Chemical Engineering and Environmental Technology at Graz University of Technology. She affirmed the project’s main objective, stating, “Our main goal is clear: to produce sustainable aviation fuel from tomato waste at a price that can compete in the market. Ultimately, these greener fuels must be financially practical.”
Over the course of the project, the two core processing technologies will be scaled up for a pre-industrial demonstration. Researchers will also be thoroughly assessing the environmental, financial, and societal impacts. This innovative use of tomato remnants is expected to generate new revenue streams for food processing businesses.
The ToFuel project is officially scheduled to begin on January 1, 2026, bringing together 11 partners from seven European nations with a total budget of USD 4.1 million (EUR 3.5 million).
