Calcium carbide produce
This highly dangerous and corrosive chemical, which is an ingredient in fertilizers is illegally used to speed up the ripening of some fruits. Calcium carbide produces acetylene gas which is similar to ethylene, a natural ripening agent in fruits when it comes into contact with moisture or water.
Fruits ripened with calcium carbide are usually very soft, have an unusual taste and have a short lifespan after harvest. They also sometimes look ripe from the outside but the tissues inside are unripe.