
Fruit ripening is a process that happens when the fruit absorbs certain gases, like ethylene, from its environment. Ethylene binds to specific receptors in the cells of the fruit which then triggers biochemical changes. This means that a ripe fruit can actually cause an unripe one to ripen faster because they are releasing more ethylene into their surroundings.

In this article we’ll show you how to take advantage of this effect for your own benefit. An unripe fruit will ripen faster if placed next to a ripe fruit because of the ethylene that they release. This is why you might see an apple or banana sitting on top of your broccoli in the produce section – it’s there so it can cause them to reach their peak freshness more quickly. The same principle applies when you store apples and oranges together, too.
When one fruits starts producing ethylene gas, this triggers changes in the other one which speeds up its own ripening process even quicker than normal. If you want some proof for yourself how well this works, just leave two pieces of bread out overnight; one with peanut butter spread thinly over it and another without anything but air touching it.