How do you tell if a banana has gone bad?

October 13, 2025 •

3 min read

According to the U.S. Food and Drug Administration (FDA), as long as a banana isn't visibly moldy, it's likely safe to eat. However, telling if a banana has gone bad involves more than just ignoring the brown spots, which are often a sign of peak ripeness for baking. This guide will help you understand the key differences between an edible, overripe banana and one that has spoiled beyond saving.

Quick Summary

This guide provides clear indicators, from sight and smell to texture, to determine when a banana has truly spoiled. Discover the differences between an overly ripe, edible banana and one that is rotten, and learn what to look for and when to compost your fruit.

Key Points

Visible Mold: The most certain sign a banana has spoiled is the presence of fuzzy, white, gray, or green mold, especially near the stem.
Off-Putting Smell: A sweet, fruity aroma is good, but a fermented, sour, or alcohol-like smell indicates spoilage.
Mushy or Slimy Texture: While overripe bananas are soft, a rotten one will feel extremely mushy or slimy to the touch.
Internal Discoloration: A black interior, not just a black peel, is a clear sign the banana is too far gone to eat.
Leaking Fluids: If the banana is leaking a watery or sticky fluid, it's a definitive sign of rot.
Black Peel is not always bad: A completely black peel is often a sign of an extremely ripe banana, perfect for baking, as long as other signs of spoilage are absent.

Visual Cues: Spotting the Spoilage

For many, the first sign of a banana's demise is a darkening peel, but this isn't always the case. A banana with a fully brown or black peel can still be perfectly good for baking, as the starches have converted to sugar, making it sweeter. True signs of spoilage are much more distinct.

Look for Visible Mold

Perhaps the most definitive sign that a banana has gone bad is the presence of mold. Unlike the dark brown or black coloring of a ripe peel, mold will appear as fuzzy patches of white, gray, or green, particularly around the stem. Once mold has formed, it is best to discard the entire banana to avoid any potential health risks.

Assess the Interior Flesh

While the peel can be entirely black, a quick check of the fruit inside is crucial. If the flesh is jet black, mushy, or discolored, it has gone bad. The interior should still have a creamy, off-white or yellowish color. If you see extensive blackness inside, it's a sign of advanced decomposition.

Check for Leaking Fluids

Rotting bananas often seep fluid from the peel as their structure breaks down. If you notice a watery, sticky residue on the fruit or the surface it's resting on, the banana is likely spoiled. This is a sign that the cell walls have broken down completely, and the fruit is no longer edible.

Sensory Cues: Smell and Texture

Beyond visual inspection, your senses of smell and touch are your best allies in determining if a banana has gone bad.

The Smell Test

Ripe bananas have a distinct, sweet, fruity aroma. As they spoil, this smell changes dramatically. A banana that smells fermented, sour, or has an alcohol-like odor has started to rot. The pungent smell is a clear indicator that the fermentation process has begun and the fruit should be discarded.

The Feel Test

Texture is another excellent indicator. A perfectly ripe banana has a firm yet soft consistency. As it over-ripens, it becomes softer and can be quite mushy, which is still fine for baking. However, if the banana feels extremely soft, mushy, or slimy to the touch, it's a sign of advanced decay. This is especially true if the softness is accompanied by other spoilage signs.

Overripe vs. Rotten Bananas: A Quick Comparison

This table helps clarify the key differences, so you can stop guessing and start knowing when to use or toss your bananas.


Feature	Overripe Banana (Good for Baking)	Rotten Banana (Toss)
Peel Color	Yellow with extensive brown or black spots.	Entirely black or dark brown, with visible fuzzy mold spots.
Interior Flesh	Still creamy, soft, or off-white. May have some brown threads.	Black, dark brown, or discolored throughout.
Texture	Very soft and mushy, but not slimy.	Extremely soft, mushy, or slimy to the touch.
Smell	Sweet and intensely fruity.	Fermented, sour, or alcohol-like.
Fluid	No leaking fluids.	Seeping fluids from the peel.

The Role of Ethylene Gas

Bananas, along with other climacteric fruits like apples and tomatoes, release ethylene gas as they ripen. This hormone accelerates the ripening process, including over-ripening and eventual spoilage. You can use this to your advantage to speed up ripening by placing bananas in a paper bag with other climacteric fruits. Conversely, separating bananas or refrigerating them (though the peel may darken) will slow down the process. For long-term storage, freezing overripe bananas is an excellent option for later use in smoothies or baking.

Conclusion: Trust Your Senses

Ultimately, figuring out if a banana has gone bad is a straightforward process that relies on your observation skills. Don't be fooled by a dark peel alone; it might just be the perfect stage for making a moist, flavorful banana bread. However, if you see mold, notice leaking fluids, or smell a fermented, sour odor, it's time to part ways with the fruit. By paying attention to these simple visual and sensory cues, you can make the most of your bananas and reduce unnecessary food waste in your kitchen.

Visit Food Hero for more tips on using overripe bananas safely and creatively.

Frequently Asked Questions

Yes, eating a banana that has gone bad with mold or is fermenting can cause food poisoning symptoms such as nausea, vomiting, or diarrhea. It's best to discard any banana with clear signs of spoilage.

A banana with a black peel can be perfectly safe to eat, especially for baking, as long as there is no mold, and the inside is not black or mushy. Black peel can be caused by cold temperatures, and the fruit inside may still be edible.

An overripe banana is still sweet and creamy, ideal for baking. A rotten banana will have mold, leak fluid, or have a sour, fermented smell. A quick smell and texture check is often enough to tell the difference.

To slow down ripening, store bananas away from other fruits, as they release ethylene gas. For even longer storage, peel and freeze them once they reach your desired ripeness.

Overripe bananas are excellent for baking due to their high sugar content. You can mash them for banana bread, use them in smoothies, make pancakes, or freeze them for later use.

Refrigeration will slow down the ripening process, but it can cause the peel to turn black. The fruit inside will still be good, but it is important to remember that cold temperatures do not prevent spoilage indefinitely.

No, it is not recommended to cut off the moldy part of a banana. Mold can have deep-reaching roots and unseen spores that spread throughout the fruit, so it is safest to throw it away.