Green bananas can ripen significantly faster when stored next to apples, according to physicist and BBC Science Focus writer Robert Matthews. The key is ethylene, a naturally occurring gas produced by many fruits as they ripen.
How Ethylene Speeds Up Ripening
Matthews explained: "Many ripening fruit produce the hydrocarbon gas ethylene as they ripen, which itself triggers more ripening." Bananas are among the most prolific producers of ethylene, making them especially effective at influencing nearby fruit. Storing green bananas alongside apples accelerates the ripening process, helping them reach their ideal yellow colour more quickly.
Two-Way Effect
The effect works both ways. A banana that is already beginning to brown can also help ripen other fruits. "Bananas are especially productive sources of the gas, and putting one that's in the process of going brown next to apples, pears or hard avocados will greatly speed up their ripening," Matthews said.
Chemical Changes Behind Ripening
Ethylene acts as a plant hormone, triggering chemical changes that soften fruit, reduce acidity, and convert starches into sugars. These changes give ripe fruit its sweeter flavour and softer texture. For shoppers hoping to avoid biting into a hard, green banana, placing the fruit in a bowl with apples could help shorten the wait.
Preventing Over-Ripening
However, the same science means fruit can spoil more quickly if left together for too long. Once fruit reaches the desired ripeness, experts recommend separating it or storing it in cooler conditions to slow the process down. The tip offers a simple, natural way to get fruit ready to eat sooner, using nothing more than the power of ethylene gas and a little patience.
