What you see: A banana with a very dark center.
What it is: Most likely a stressed banana that’s still holding it together.
Eat or toss: If it looks normal, but just blackened, it’s fine. Eat!
Why do some bananas go dark at their centers?
If a banana’s core is going dark, stress is probably the cause, said Jeff Brecht, a professor of postharvest physiology and horticulture at the University of Florida. Most likely, he said, the banana pictured here was stored at too-high temperatures between harvest and the consumer (think 86 degrees Fahrenheit or hotter). Certain growing conditions, too-cold temperatures after harvest and an internal bruise could also lead to darkened banana centers.
Can you eat a banana that’s black in the middle?
The discoloration does not render the banana inedible.
“I would eat it and I have eaten bananas like that,” Brecht said of the image at the top of this post.
Whether from a bump or hot or cold stress, when a fruit discolors anywhere it’s usually because cells membranes have gone leaky, causing components normally kept separate to mix and react with each other and oxygen. Those reactions—all physical responses within the banana—lead to brown and black colors. Such activity could theoretically lead to off flavors in a banana like this, but Brecht said the baseline flavor of a banana would probably be so strong that you wouldn’t notice anything amiss.
Banana seed remnants blacken first
Wild bananas have black seeds, about the size of a bean, Brecht said. While our supermarket bananas are, of course, seedless, tiny bits of would-be seeds remain. In a stressed banana like this, those areas where the seeds would have been tend to turn brown and black first.
And to go even deeper into the nifty botany of this scenario, take a close look at the image and you’ll see three clusters of black. While bananas seem uniform to us, the fruit are actually made up of three sections, each of which houses a collection of seeds that never were. That three-part structure can be traced back to the portion of the flower destined to become the fruit; it also had three sections. If you squeeze a peeled banana just right, it will easily separate into those three units.
Could black inside a banana indicate a disease or bacteria?
If part of a banana looks unnaturally slimy or smells foul, that indicates microbial growth—not something you want to eat. But consider that for a microorganism to get into a banana, it needs an access point, like a break in the skin. If the banana was intact and uninjured before you peeled it, and simply looks a little black at its center, a physiological issue within the banana is by far the most likely explanation.
