A virtually invisible coating of silk solution could keep fruit fresh for up to a week without any refrigeration.
Silk is one of the toughest natural materials, and an insoluble protein within it called fibroin is able to stabilise and protect other materials.
Researchers dipped freshly picked strawberries into a solution of 1% silk fibroin protein, then treated it with water vapour in a vacuum.
The strawberries were then stored at room temperature for a week, after which they were still juicy and firm.
Meanwhile, a control portion of uncoated strawberries had become dehydrated and discoloured.
Scientists from Tufts University said that the silk coating prolonged the fruit's freshness by slowing its respiration.
Study author Fiorenzo Omenetto said: "The beta-sheet content of the edible silk fibroin coatings made the strawberries less permeable to carbon dioxide and oxygen.
"We saw a statistically significant delay in the decay of the fruit."
A subsequent study also found that the system works on bananas too - decreasing the ripening rate and preventing the softening of the peel.
The silk coating is odourless, and did not affect the fruit's feel, however the taste effects have not yet been studied.
Half of the world's fruit and vegetable crops are lost in the food supply chain, according to the United Nations, usually due to premature deterioration.
A breakthrough in preservation techniques could help to bring down the shelf price of fresh produce.
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