Science gets under the skin

Radical UV technology that gets under the skin of fruits and vegetables to extend their shelf-life is being tested by Campden & Chorleywood Food Research Association (CCFRA).

Traditionally, UV has been used for surface sanitising, said CCFRA project co-ordinator Nick Saunders. "But if you apply it in very low doses to things like broccoli, tomatoes and strawberries, it induces a process called hormesis, a stress response in the fruit that makes it produce antifungal enzymes."

Unlike conventional UV treatment, the effects were not restricted to the surface of the fruit, but were "manifested throughout the plant tissue", he said. "You're effectively stimulating the fruit's natural defences. If we can do it on an industrial scale in a consistent and cost-effective way, we could significantly reduce food waste. We haven't done a cost-benefit study yet. But if you think of what a difference even an extra day of shelf-life could make to a high value fruit like strawberries, you can see why this has generated so much interest."

Working with the University of Nottingham and Loughborough University, CCFRA is mid-way through a one-year feasibility study to test the stability of low dose UV-treated fruits and vegetables under commercial storage conditions. The study, which has been part-funded by the Department for Environment, Food and Rural Affairs, would also seek to determine optimum dosages and exposure times, he said. "After that, we want to explore the business case for applying the technology on an industrial scale."

It was difficult to quantify the business case at this stage, he said. But it was well known that up to 30% of certain crops, such as broccoli, were wasted post-harvest, which hinted at the size of the prize if the technology were commercialised.

"A successful outcome of this project is likely to bring very substantial financial benefits at all stages of the supply chain."