Japanese researchers have developed a foam sheet that can be used in packaging and for distribution, which uses the extracted enzymic fluid of bamboo to preserve the freshness of fruits and vegetables. Plusto Co., Ltd and the Faculty of Engineering, Keio University, have jointly developed the wrapping, which absorbs and decomposes the ethylene gas emitted by fruit and vegetables that promotes ripening. The idea is that the wrapping would allow the delivery of unripe fruits, even if they had been shipped for some time. The researchers claim that the method is safer than other preservation agents, such as potassium permanganate.