Xihong Li, a Chinese researcher has developed a spray-on coating, a hydrogel, to delay the ripening of bananas. The hydrogel is made from chitosan, a substance derived from shrimp and crab shells. As millions of consumers are allergic to shellfish it is expected that there will be an outcry of opposition from concerned consumers.
The research was presented on the 22nd of August 2012 in Philadelphia at the 244th National Meeting & Exposition of the American Chemical Society. The purpose of the hydrogel coating is to delay ripening of approximately 6.4 billion pounds of bananas that consumers in the U.S eat every year.
“We found that by spraying green bananas with a chitosan aerogel, we can keep bananas fresh for up to 12 days,” said Li, who is the study’s leader. “Once bananas begin to mature, they quickly become yellow and soft, and then they rot. We have developed a way to keep bananas green for a longer time and inhibit the rapid ripening that occurs. Such a coating could be used at home by consumers, in supermarkets or during shipment of bananas.”
Li explained that bananas have a porous quality and breathe and respire, taking in oxygen and releasing carbon dioxide- through their skin. The more a banana respires the more it ripens. It follows that the same porous quality will allow a shellfish coating to be absorbed into the actual fruit, amalgamating with the very essence of a banana.