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Silk prevents food wastage

Posted on 04 October 2016.

Covering fresh fruit with silk - American engineers have found a solution that could considerably limit waste when transporting this perishable commodity.

The figures are alarming. According to the Food and Agriculture Organization (FAO), 50% of the fruit and vegetable production destined for our plates all year round is discarded because it has deteriorated during transport... As a result, various conservation methods have been developed, but none are completely satisfactory. For example, chilling has the disadvantage of altering these fragile foodstuffs and in addition uses a lot of energy. The experiments conducted by biomedical engineers at the American Tufts University (Medford-Oregon) could therefore offer an interesting solution that would reduce the huge amount of waste.

Invisible and biodegradable silk protein

These researchers made a major discovery - they demonstrated that fruit will remain fresh for over a week without refrigeration, provided it is covered with silk. But it’s not a question of rushing to our closets to grab that lovely silk blouse and throw it over the strawberries! It is actually a biocompatible, biodegradable and odorless solution of silk fiber proteins called fibroin, so fine it is invisible.

Seven days at room temperature and still just as fresh

After storing raspberries in this silky bath for seven days at room temperature, the researchers found they were still as juicy and firm, without any signs of deterioration. The engineers then moved on to bananas, which have the particularity of continuing to ripen after harvest - eventually turning black and soft. Once covered with this silk fibroin, the banana skins were firmer and ripening was slower. Although the researchers admit they didn’t check whether the taste of the fruit had changed, the experiment opens up a range of possibilities for keeping food without refrigeration or chemical treatments.