Two Ugandan entrepreneurs have been honoured with top accolades at the European Patent Office’s 2025 Young Inventors Prize, earning praise for a biodegradable sachet that extends the shelf life of fruit without refrigeration.
Sandra Namboozo, 26, and Samuel Muyita, 28, were awarded both the People’s Choice and the Community Healers awards for their invention, Karpolax, which uses plant-based compounds to delay ripening and reduce spoilage.
The sachet, placed inside fruit packaging, releases a blend of natural volatile organic compounds sourced from cloves, lemongrass, eucalyptus and wintergreen. These compounds slow the fruit’s release of ethylene gas and guard against mould, fungi, and bacteria.
“There is a huge problem of food waste from farm to consumer, and that is what we are trying to solve,” said Muyita.
Pilot studies carried out with Uganda’s National Agricultural Research Organisation (NARO) showed that Karpolax extended the shelf life of mangoes from 11 to 33 days. Similar results were seen in tests involving apples, oranges, bananas and other fruits.
In regions where cold storage is limited or unaffordable, the sachets offer an alternative means of preserving produce—particularly for smallholder farmers.
Since launching in 2020, the technology has reportedly prevented the spoilage of over one million tonnes of fruit, supporting more than 100 farmers, 20 exporters, and 250 vendors. The sachets, which currently retail at around UGX2,500 (EUR 0.60), are now being adapted for use with other crops including pineapples and berries.
“One sachet can preserve up to five kilograms of fruit for 30 days,” said Namboozo, who also works with the Uganda National Oil Company.
The duo developed the idea while studying at Makerere University, where Namboozo pursued industrial chemistry and Muyita specialised in civil and environmental engineering.
Convincing stakeholders, they said, was initially challenging.
“Many thought it had synthetic chemicals that might affect the fruit’s quality,” Namboozo said. “But it’s entirely organic.”
The inventors were among ten finalists under 30 selected from more than 450 applicants worldwide. In addition to the €5,000 base prize, they received €5,000 from the public vote and €15,000 for the Community Healers award, which recognises social impact.
Their work was commended for contributing to the United Nations Sustainable Development Goals, particularly Zero Hunger and Responsible Consumption.
“Winning a special prize is a powerful validation—not just of our work, but of the farmers we serve,” the pair said in a joint statement. “It shines a global spotlight on a simple truth: innovation rooted in empathy can change the world.”
According to the UN Framework Convention on Climate Change, more than one billion tonnes of food were wasted globally in 2022. In the same year, 783 million people faced hunger.
With growing international interest and new funding, the Ugandan innovators hope to scale up production and reach new markets.
