Why Do Bananas Turn Black in the Refrigerator?

Published on Thursday, May 27, 2010, by Roxanne Webber / Edit Post

Bananas, like other tropical fruits, are prone to “chilling injury”; that is, damage from cold storage. The most obvious sign of it is when yellow banana skins turn black after refrigeration.

If the bananas were fully ripened before you refrigerated them, they’ll still be fine to eat, though they’ll be mushy and the flesh might also have turned brown.

Banana skins are made up of plant cells. In each of those cells there is a vacuole, a little fluid-filled compartment that’s contained by a membrane. When a banana gets too cold, the membranes weaken and leak. Adel Kader, a professor emeritus in the Department of Plant Sciences at UC Davis, explains that phenolic compounds that are in the vacuole along with the fluids mix with polyphenol oxidase, an enzyme found in the cell’s cytoplasm (that’s the jellylike stuff that parts of a cell hang out in). The phenolic compounds oxidize and form a brown compound called melanin.

If the bananas weren’t ripe to begin with, Kader says, they probably won’t ever ripen properly, another symptom of chilling injury. The best bet for banana storage is to keep the fruit at room temperature.

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  • I'm Chiquita banana and I've come to say
    Bananas have to ripen in a certain way.
    When they are flecked with brown and have a golden hue
    Bananas taste the best and are the best for you.
    You can put them in a salad.
    You can put them in a pie.
    Any way you want to eat them,
    It's impossible to beat them.
    But bananas have to ripen at the very, very tropical equator.
    So you should never put...+READ

    I'm Chiquita banana and I've come to say
    Bananas have to ripen in a certain way.
    When they are flecked with brown and have a golden hue
    Bananas taste the best and are the best for you.
    You can put them in a salad.
    You can put them in a pie.
    Any way you want to eat them,
    It's impossible to beat them.
    But bananas have to ripen at the very, very tropical equator.
    So you should never put bananas in the refrigerator.
    Oh, no, no, no!-COLLAPSE

  • Here in FL, we often put bananas in the fridge when they have perfectly ripened, because many of us grow them, and 5-6 hands may be ready at a time. The inside is usually fine. I found that the ethelyne absorbing storage bags lowered the overall ethelyne in the fridge. Now the skins don't turn black overnight. There's some discoloration, but they still look appealing, and it's better than having...+READ

    Here in FL, we often put bananas in the fridge when they have perfectly ripened, because many of us grow them, and 5-6 hands may be ready at a time. The inside is usually fine. I found that the ethelyne absorbing storage bags lowered the overall ethelyne in the fridge. Now the skins don't turn black overnight. There's some discoloration, but they still look appealing, and it's better than having them go to the compost pile. For teething babies, you can also mash, fold into a stick shape, and freeze.-COLLAPSE

  • Freezing peeled leftover bananas with a little lime juice is excellent if you want to use them in future for banana cake, too (for which you'd need to mash them anyway, so no difference). And the aside about cell phones was just inappropriate to this forum and pointless, so let's stick to the food talk, yes?

  • Once my bananas are ripe I just peel, put them in the freezer in a zip lock for shakes. Yummy with protein power. Well, I guess many have not heard the jingle which I think was from Chiquita Banana commercial "never put bananas in the refrigerator", which I learned from my mom singing this little tune when I was a tot years ago. She also made homemade pizza, and I guess that's why I like CHOW!

  • To albgardis:

    I don't know you at all, and you're certainly entitled to your own opinions about anything. I guess I'd just wonder why you're here if you have such a low opinion of Americans. Are you stuck here somehow? Too bad you suffer so.

    Actually, refrigeration helps preserve most food products and helps keep many fruits and vegetables from over-ripening. Not all benefit from...+READ

    To albgardis:

    I don't know you at all, and you're certainly entitled to your own opinions about anything. I guess I'd just wonder why you're here if you have such a low opinion of Americans. Are you stuck here somehow? Too bad you suffer so.

    Actually, refrigeration helps preserve most food products and helps keep many fruits and vegetables from over-ripening. Not all benefit from refrigeration...... you're right about that.

    Oh..... and the thing about cell phones................... it isn't that Oprah has to remind Americans that driving while on the phone is dangerous. They know it! They're just too self-centered to think that they might be the one who kills someone due to being distracted. It's now illegal in California but I see people doing it every day. It's dumb, but no more dumb that shaving or applying makeup or reading !!!!...... which I see as well.-COLLAPSE

  • Ah, that explains why my bananas turn brown. So what's the deal about hanging banana's with a proper banana rack? I've personally found that it last longer that way, but what's the REAL reason?

  • Regardless of the great refrigeration we have available in the US, and the propensity of Americans to use it to excess, I know of no one who refrigerates bananas. I happen to like my melons and oranges chilled, however.

    What do bananas and cell phones have to do with each other?

  • Interesting to read that it needs to be mentioned that bananas don't belong in the fridge. I am not American and often have these weird "duh" moments, when Americans have to be explained to most obvious. Like this.

    Same goes for tomatoes, melons, onions, oranges and probably other items I can't think of right now.

    Same category: cell phones while driving (forbidden in my country, for a...+READ

    Interesting to read that it needs to be mentioned that bananas don't belong in the fridge. I am not American and often have these weird "duh" moments, when Americans have to be explained to most obvious. Like this.

    Same goes for tomatoes, melons, onions, oranges and probably other items I can't think of right now.

    Same category: cell phones while driving (forbidden in my country, for a reason).
    It takes Oprah to make a campagne to inform american people that driving while speaking with their cell phones is actually dangerous!!!

    Duh...
    No, really?
    You think it is?-COLLAPSE

  • Freezing them is convenient if you have some leftover that you don't want to consume, and it's also great for making frozen daiquiris or smoothies. Not for eating them.

  • Here is the best remedy to safe Bananas those are turning black while refrigrate -

    Buy Bananas which you can consume within 12 hrs. so no need to store!!!!!!!!!!!!!!!!!!!!!

    ashutosh

  • I just keep them at room temp.

  • If you freeze them peeled w/ a little lemon/lime juice squeezed on them, they won't turn brown in the freezer.

  • I find I can preserve a banana that's turning dark brown for another few days without much ill effect on the fruit itself by refridgerating...