Mason Jars Keep Bananas Fresh Longer Than You'd Expect

Trying to keep bananas fresh is a battle everyone faces at some point. You buy a bunch that are a little green and put them on the counter. By the time you reach the last one or two, there's a good chance they've developed some serious brown spots. It gets even trickier if you only want half a banana and try to save the rest for later. The window of freshness for that banana, no matter how you wrap it, is very narrow. But there is a method to preserve bananas that you might not have tried, and all you need is a mason jar.

A typical banana, once ripe, will only stay at its freshest for a few days. Even in the fridge, an already ripe banana will last no more than a week. If you cut a banana in half, whether to use a small portion or to make a snack for a child, the remaining half has a much shorter shelf life. Exposure to air speeds up the browning exponentially. But a mason jar can extend the life of that banana, not just for a few hours, but for days. In fact, you could potentially store cut bananas for up to an entire month in a sealed jar without them turning brown. The key is to leave the peels on, seal the jar tightly, and refrigerate it.

Bananas turn brown thanks to ethylene gas. Ethylene is a hormone that activates enzymes in the banana, advancing the ripening process. It's what causes bananas to go from yellow to brown, get softer, and become sweeter. Bananas produce this gas themselves, so it can't be avoided. This is why, if you want bananas to ripen faster, you put them in a paper bag. It also explains why putting them next to other ethylene-producing fruit makes them spoil too fast.

Usually, cutting a banana greatly speeds up the ripening process. That said, lowering both temperature and oxygen levels prevents bananas from producing ethylene. Bananas need air and warmth to make the hormone. But cutting that off in a jar in the fridge, the fruit ripens at a much slower pace.

You can't keep a banana in a jar indefinitely, of course. It's also still at risk of bacteria. That's why it's important to keep the peel on. It naturally preserves the banana better than anything else you could wrap it in. But if you have a chronic problem with bananas ripening too quickly, this could be the solution you need. Don't forget to save those banana peels when you're done.

You don't need to try to keep bananas fresh for an entire month. They will be very soft after 30 days, but you can still get a few extra days of life by storing them this way. If you're tired of throwing away the last couple of bananas in the bunch, invest in a few jars and keep those bananas preserved in the fridge until you're ready to eat them. We have a few suggestions for how to use overripe bananas until then.