Forget refrigeration, now silk coating can keep your favourite fruit fresh

Zee Media Bureau

New Delhi: For all those who love eating their fruits fresh and chilled, here comes an easy alternative.

Now, you can keep your fruits fresh by coating them in odourless, thin and biocompatible silk solution for more than a week.

The crystalline structure of silk makes it one of nature's toughest material.Fibroin, an insoluble protein found in silk, has a remarkable ability to stabilise and protect other materials while being fully biocompatible and biodegradable.

For the study, the researchers dipped freshly picked strawberries in a solution of one percent silk fibroin protein. The coating process was repeated up to four times. 

The silk fibroin-coated fruits were then treated for varying amounts of time with water vapour under vacuum (water annealed) to create varying percentages of crystalline beta-sheets in the coating. 

The strawberries were then stored at room temperature. Uncoated berries were compared over time with berries dipped in varying numbers of coats of silk that had been annealed for different periods of time. 

At seven days, the berries coated with the higher beta-sheet silk were still juicy and firm while the uncoated berries were dehydrated and discoloured.

Tests showed that the silk coating prolonged the freshness of the fruits by slowing fruit respiration, extending fruit firmness and preventing decay.

(With IANS inputs)