Got an overripe banana? Don't throw it away. Unless there is mold on it, this delicious fruit can add flavor to cookies, milkshakes, pancakes and energy-boosting smoothies.
Fully ripe bananas don't pose any health risks. In fact, they're actually more flavorful and nutritious compared to their green counterparts. Those tiny brown spots don't affect their quality or aroma. A rotten banana, on the other hand, can be contaminated with mold and should be discarded.
Overripe bananas that have mold or strange odors are not safe to eat and should be discarded. Brown spots and bruises, on the other hand, don't affect their nutritional value.
Are Overripe Bananas Edible?
About one-third of the food produced worldwide goes to waste, reports the Food and Agriculture Organization of the United Nations. Fruits and veggies have the highest wastage rates. In fact, more than 3.7 trillion apples will never end up on consumer's plates.
Compared to most fruits, bananas have a short shelf life and can go from green to dark brown within days. For this reason, they often get discarded, which further contributes to food waste.
Believe it or not, overripe bananas are perfectly safe to eat. They actually boast higher vitamin C and antioxidant levels, according to a 2014 study published in the International Food Research Journal (Volume 21). Their peel may change its color or develop brown spots, but the flesh is still edible.
According to the Greater Chicago Food Depository, most fruits that are bruised or look damaged can be safely used. Melons, for example, may have bruises and deformed rinds, but this doesn't mean you should throw them away. The same goes for bananas — these delicious fruits don't pose health risks as long as they are not extremely overripe. You can simply remove the brown spots with a knife, cut the fruit into chunks and freeze it for later use.
What Makes Bananas Rot?
Unfortunately, there's a fine line between a rotten banana and one that's overripe. These tropical fruits can quickly turn brown because of ethylene gas, a phytohormone. Its levels increase as bananas approach maturity. Avocados, apples, plums, peaches, tomatoes and other climacteric fruits are all major ethylene producers, which is why they continue to ripen after harvesting.
Ethylene can turn most fruits into a mushy mess. This gaseous compound affects their texture and appearance, causing them to soften and rot.
Simple things, such as storing your bananas in the refrigerator and wrapping them in plastic, may help suppress ethylene production. A study published in the Journal of Food Science and Technology in November 2014 found that storing bananas in polyethylene bags, such as Ziploc bags, may increase their shelf life, reduce water loss and keep them fresh for longer.
There are some instances, though, where overripe bananas may not be safe to eat. Mold is of particular concern as it may cause allergic reactions and respiratory issues, warns the USDA Food Safety and Inspection Service.
Some molds produce dangerous toxins that may cause organ damage, neurodevelopmental disorders and neuropsychological symptoms. If you notice signs of mold on bananas, wrap them in paper or plastic to protect children or pets, and discard them immediately.
Louisiana Fresh states that bananas with black or moldy stems may not be safe. Also, make sure there are no soft spots. If the fruits have an unusual color, such as gray or dull yellow, they may have been stored improperly. A strange odor might be a sign of mold or spoilage, in which case you should discard the fruits.
Storing an Overripe Banana
So, what's the best way to store bananas? Should you keep them in the freezer or put them in a basket on your countertop? Louisiana Fresh recommends refrigerating bananas once they are ripe. Green bananas can be placed in sealed plastic bags and stored in a warm place.
According to Cooking Light, one way to keep these fruits fresh for longer is to keep the peel on after cutting them. This will help reduce oxidation and maintain their freshness. If you're planning to make a fruit salad or decorate homemade desserts with banana slices, spray citrus juice over the fruits to prevent oxygen from reaching their surface. Vinegar works well, too.
Dole recommends storing bananas at around 53.6 degrees Fahrenheit (12 degrees Celsius), away from direct sunlight, until they are ripe. You may also wrap their stems in plastic to slow the ripening process.
Like most fruits, bananas can be stored in the freezer. Beware, though, that freezing may affect their nutritional value. To prevent this issue, store them at 0 degrees Fahrenheit (-17.7 Celsius) or lower, a temperature usually attainable in standalone freezers or some separate refrigerator-freezer units. This applies to most fruits and vegetables.
- Food and Agriculture Organization of the United Nations: "Key Facts on Food Loss and Waste You Should Know!"
- International Food Research Journal: "Changes in Antioxidant Properties and Chemical Composition During Ripening in Banana Variety ‘Hom Thong’ (AAA Group) and ‘Khai’ (AA Group)"
- Greater Chicago Food Depository: "Salvageable Fruit and Vegetable Guidelines"
- International Journal of Food Science: "Induced Ripening Agents and Their Effect on Fruit Quality of Banana"
- Journal of Food Science and Technology: "Effect of Packaging Materials on Shelf Life and Quality of Banana Cultivars (Musa Spp.)"
- USDA Food Safety and Inspection Service: "Molds on Food: Are They Dangerous?"
- Clinical Therapeutics: "Effects of Mycotoxins on Neuropsychiatric Symptoms and Immune Processes"
- Louisiana Fresh: "Bananas"
- Cooking Light: "How to Store Cut Bananas So They Last Longer and Taste Their Best"
- Dole: "Storing Bananas Correctly: Do’s and Don’ts"
- Philadelphia Magazine: "How to Keep Bananas From Turning Brown"
- University of Minnesota Extension: "The Science of Freezing Foods"
- USDA FoodData Central: "Raw Bananas"
- "Cooking Light": Best Banana Breads