Banana Experiment: Which Will Ripen First?

I really love experiments that are easy for kids to set up and don’t require a lot of materials. This banana experiment meets both of those criteria. We wanted to find out which banana would ripen first. Then, we talked about what makes bananas (and other fruit) ripen in the first place.

Banana Experiment: Which Will Ripen First?

Here’s What You’ll Need:

• Green bananas (or as close as you can get)
• Plastic baggies
• Different types of fruit (we used an apple, an orange, and a lime)

The day you buy your bananas is the day you’ll want to start the experiment. I found a bunch of nice green bananas at the store. We weren’t ready to set up the experiment until the next day. The green bananas happened to be sitting next to the really ripe bananas we already had. (I didn’t put them there.) Needless to say they were no longer green… I had to go to the store 3 more times before I found the somewhat green ones we ended up using.

Place each piece of fruit with a banana in a plastic baggie. Add only a banana to one plastic baggie. (This is your control group – your basis for comparison.) Do not close the plastic baggies.

Store the baggies in different locations that have the same environment (put them in the 4 corners of your bedroom away from light).

Check on the bananas once a day and observe any changes. Which one starts to ripen first?

3 days later ours looked like this.

After 8 total days, our bananas looked like this.

On Day 7, there was actually a bigger difference in the bananas. The banana alone still had very little brown on it. It’s interesting that in one additional day, the banana alone turned brown, too. I wouldn’t have expected the result with the orange. I’m guessing the banana is brown due to being handled too much by the kids. The stem is still quite green.

The Science Behind It

Fruits and vegetables produce ethylene gas which among other things causes fruits to ripen. Fruit that is already ripe releases more ethylene than fruit that is not ripe. As bananas ripen, they turn from green to yellow, the peel softens, and the fruit becomes sweeter. The soft peel is prone to bruising. When exposed to oxygen, the bruised peeled will turn brown. The apple, lime, and orange give off ethylene gas which causes the banana to ripen. We left the baggie open so oxygen could get in and turn the banana brown. Of the 3 types of fruit we used, apples are give off the most ethylene gas. Limes and oranges release a very small amount of ethylene. It’s also interesting to note that when exposed to ethylene, citrus fruits will mold. So our bananas had an effect on the lime and orange as well.

More Plant Experiments for Kids

• Plant Science Experiment inspired by Peter Rabbit – test which plant will grow the best in different conditions.
• Build a Lemon Battery (sponsored post) – How many lemons does it take to build a battery? Can you use other fruit, too?
• Design a Leaf that Will Keep Water from Evaporating

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