Ugandan entrepreneurs Sandra Namboozo (26) and Samuel Muyita (28) have scooped both the People’s Choice and Community Healers awards at the prestigious 2025 Young Inventors Prize, organised by the European Patent Office (EPO). The duo was recognised for their groundbreaking innovation, Karpolax—a biodegradable sachet that preserves fruit freshness without refrigeration. The invention impressed both the public and an independent jury. The sachet, placed inside fruit packaging, emits a blend of plant-based volatile organic compounds derived from cloves, lemongrass, eucalyptus, and wintergreen. These compounds suppress ethylene emissions to slow ripening and protect against mould, fungi, and bacteria.
In pilot trials conducted with the National Agricultural Research Organisation (NARO), Karpolax extended the shelf life of mangoes from 11 to 33 days. The technology has also been tested successfully on bananas, apples, and oranges.
The innovation offers a critical solution for smallholder farmers in sub-Saharan Africa, where cold storage facilities are often unavailable or unaffordable.
Since its launch in 2020, Karpolax has supported over 100 farmers, 20 exporters, and 250 vendors, helping prevent the spoilage of more than one million tonnes of fruit. The sachets are now being adapted for use with pineapples, capsicum, and berries.
“One sachet can preserve a five-kilogram box of fruit for up to 30 days, after which its active ingredients are used up,” Namboozo explained.