Many grocery stores bind banana stems in plastic wrap to keep the fruits perfectly ripe and fresher for longer. It’s essentially an ingenious way to reduce food waste.

Before bananas are picked from the tree, they have a steady state of a gas called ethylene. However, picking them exposes their stems to air, causing the stems to release ethylene.

As the bananas get picked, the increased exposure to ethylene turns off genes within the bananas that are responsible for growth, which, in turn, causes them to ripen continually.

Covering the stems of picked bananas with plastic wrap or even foil can reduce the amount of ethylene produced by the stems, which ultimately

slows the ripening process.