A novel fruit wash developed by researchers at the University of British Columbia (UBC) promises a dual solution to common concerns for consumers and the produce industry: effectively removing pesticide residues and significantly extending the shelf life of fresh fruits.
Tackling Pesticide Residues
The biodegradable formulation, still in its developmental stages, has demonstrated remarkable efficacy in laboratory tests. It combines plant-based materials with iron to create a fine network around starch particles. During washing, this structure actively interacts with and helps remove certain pesticide molecules from the fruit's surface.
Tests on apple surfaces showed the new wash removed over 85% of thiabendazole. In comparison, tap water removed only 48%, baking soda achieved 65%, and native starch removed 61%. The innovative wash also proved highly effective against other common pesticides, eliminating 93% of acetamiprid and 89% of imidacloprid residues from apples.
Slowing Spoilage and Enhancing Freshness
Beyond pesticide removal, the formulation can form a thin, protective coating on the fruit after washing. This light surface film helps slow moisture loss and deterioration, a critical factor for maintaining produce quality.
In trials, untreated grapes lost approximately 45% of their weight over 15 days, while grapes treated with the new wash lost only 21%. Similarly, fresh-cut apple slices showed a reduction in weight loss from 17% to 9% over 48 hours after treatment. Treated produce also maintained a fresher appearance, with apple slices browning more slowly.
Future Applications and Limitations
While promising, researchers emphasize that this fruit wash is not yet ready for household use. Its initial application is envisioned for post-harvest processing facilities, where conditions for concentration, treatment time, water use, and disposal can be carefully controlled. The estimated raw-material cost for treating an apple is less than US$0.032.
An important distinction is that the wash targets surface pesticide residues. Pesticides that have been absorbed into the plant tissue during growth are significantly harder to remove. Therefore, this formulation is not a complete solution to all pesticide exposure but offers a substantial reduction in surface contaminants.
The UBC team is also exploring a household spray formulation, but extensive further testing across a wider range of fruits and vegetables, under commercial conditions, and through regulatory processes, is required before it can reach consumers.