An international research team is developing nanotechnology-based applications of hexanal, a natural plant extract that extends the storage life of harvested fruit.
Bananas, mangoes and papayas: these tender tropical fruits are in high demand in export markets and an important livelihood source for producers. But freshness is key because these fruits spoil quickly and damage easily. The challenge is especially daunting where refrigeration is lacking. Estimates suggest that up to 40% of produce in tropical countries is lost in post-harvest handling.
Breakthrough research by Canadian, Indian, and Sri Lankan partners points to a promising innovation: nanotech applications of a natural plant extract called hexanal can be used to delay fruit ripening. Hexanal inhibits a plant enzyme that is responsible for breaking cell membranes during a fruit’s ripening process.
In initial research in India and Sri Lanka, scientists used a hexanal-impregnated formula to test the product on mangoes. Spraying orchards with a low concentration of the compound slowed fruit ripening by three weeks. The team is also developing “smart packaging” systems, made from materials such as banana fibre, that slowly release hexanal to extend storage life after fruit is harvested.
These applications can boost farmers’ incomes. “Let’s say a mango farmer sprays half or one third of the orchard with the formulation,” explains Jay Subramanian, a professor at Canada’s University of Guelph. “He gets that same mango production but spread out over a three- to four-week window instead of just one week, which causes a major rush and a glut in the market, leading to low prices.”
In field trials, farmers were able to earn up to 15% more for their crop. Once harvested, the sprayed mangoes remained fresh for up to 26 days in cold storage and 17 days at room temperature.