Potatoes . . . when to toss?

An AnswerLine caller asked:  “Should a potato with sprouts be used or tossed?”

Potatoes with sprouts (little green, white or pink nubs), are safe to eat per Dr. Benjamin Chapman, associate professor and food safety specialist at North Carolina State University.  He recommends that you simply cut out the shoot with a paring knife before cooking, making sure to take off a bit of the surrounding area, too.  If the potato is still firm, most of the nutrients are still intact.  Sprouting occurs when potatoes are exposed to conditions that are either too warm or too bright.  Potatoes should be stored in a cool, dark place where the temperature hovers around 50 degrees and there is good air circulation.  Do not refrigerate potatoes.  Cold temperatures convert starch to sugar, giving potatoes an uncharacteristic sweet taste.  The sugar caramelizes during cooking producing brown potatoes and an off flavor.  Potatoes can be stored for a week or two at room temperature enclosed in a paper bag or a dark pantry with good results.

So when is it time to toss a tater?  University of Illinois Extension recommends that soft, shriveled, or wrinkled potatoes with or without sprouts should not be eaten.  What about green potatoes?  Green skin potatoes have been exposed to too much light.  Light causes the potato to produce chlorophyll and also solanine.  Solanine has a bitter taste and is an irritant to the digestive system that can cause paralysis in large quantities. Beth Waitrovich, Michigan State University Extension Specialist, says “small green spots can be trimmed off; however, if it’s more than a small spot, throw the potato out.  Do not use any green potatoes, trimmed or not, if you are serving children as they have a lower body mass and would be more susceptible to the solanine.”  If potatoes have a bitter taste, do not eat them.  For more information on green potatoes, see Green Potatoes:  Causes and Concerns by the University of Alaska Fairbanks.

For other questions about food safety and storage advice that will help keep food safe after purchase or harvest, there is an excellent resource:  The Food Keeper.  This handy reference tool was prpduced by the Food Marketing Institute at Cornell University in conjunction with the United States Department of Agriculture (USDA).  It contains useful guidelines about how long you can safely store food;  to keep this valuable information at your fingertips there is also an app available for IOS or Android smartphones.  Visit the App Store or Google Play and search for “FoodKeeper Mobile App.”

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

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20 thoughts on “Potatoes . . . when to toss?

  1. Some say potatoes that are a little soft are okay, while others are saying there not okay:/…..so confused

  2. Lisa, thank you for contacting AnswerLine. It really depends upon how shriveled or soft the potatoes are. Potatoes that are slightly soft are safe to cook and eat; the softening is due to natural moisture loss. Soft, shriveled, or wrinkled potatoes with or without sprouts should not be eaten.

  3. I have some potatoes that are wrinkly looking but they are not really soft, And just a few of them have some small white sprouts on them. Are they okay to still keep or just toss the bag of potatoes away?

  4. Darlene, they are still okay to use but you may or may not notice a change in the quality.

  5. I have some organic potatoes that have gone soft and have sprouts on them. They are not green anywhere but they are soft. Is it ok to plant them?

  6. Hi Sharon, Organic, soft and sprouting potatoes are fine to plant. If you live in the midwest or northern part of the US, it is too late in the season to expect any kind of crop.

  7. Hi there,

    I recently boiled and roadster some basic white potatoes that where three weeks after the best before date (they were only slightly soft and visibly more yellow). Once roasted, I tried a few pieces and they are much sweeter than usual. Is this normal and are they safe to eat?

  8. Hi Stella, the potatoes you roasted are safe to eat; when they become really shriveled and soft is when there is a concern and should be tossed. It is quite likely that the potatoes tasted sweeter as well; there are two reasons. The starches in the potatoes were slowly converting to sugar which caused them to soften. Secondly, roasting vegetables tends to bring out their sweetness in the best way; in this cause you not only had roasting to bring the sweet flavor out, you had starches that were changing, too.

  9. I ordered a lot of potatoes and some of them were exposed to freezing temps while on the truck. They are dark next to the skin but the rest of the potato is fine. Can I bake and serve them?

  10. Hi Nannette, The Idaho Potato Commission says “that the short answer is NO. Once frozen the cell structure changes as well as the taste. They will turn black when cooked. Sorry, I am sure you were hoping for a different answer.” Knowing this, you will have to make a decision as to what may or may not be salvagable by experimenting to see what happens.

  11. Hi Yoshi, if the potatoes are just a little soft or have a few small sprouts, they are fine to eat. Potatoes are 80 percent water, so softness is usually just a sign of dehydration which comes with aging. But if they’re extremely mushy or shriveled, they should be tossed.

  12. Hi Marlene! I grow, or try to grow potatoes in my New England yard. Though I got a fair number of larger potatoes, I get a vast majority of smaller potatoes which I put in stews. At this point in the season, February, the rest of the smaller ones are starting to sprout and are pretty soft. I hear that I should not eat them. Here are my questions: Why not eat them? I boil, mash with the skins on, and use them, and I find that they plump up with boiling. Is there a nutritional reason to not eat them? They are not rotted, …yet. I just can’t see throwing them out. The second part of my question is how do I get all big potatoes, or is the smaller potato standard? All the cooking and gardening shows show all large potatoes. What am I doing wrong?
    Thank you! Best, Bill

  13. Hi Bill, The general rule for knowing if uncooked potatoes have spoiled include a soft/mushy texture, the potato has a bad smell, or there are dark spots on the skin. If none of these signs are evident, the potatoes may be used; shriveling is due to the natural loss of water; potatoes are 80 percent water at the time of digging and as they sit, the water dissipates causing them to shrivel. Spoiled potatoes can be poisonous. The potato plant contains a neurotoxin called solanine. Do not eat the sprouts and be sure to core out the eyes where the sprouts are forming. Solanine is concentrated mostly on the skin or in the sprouts. Consuming bad potatoes can cause solanine poisoning. While rare, symptoms include headaches, vomiting, fever, stomach cramps, and difficulty in breathing. Other symptoms include diarrhea, shock, and hallucinations.

    Since I do not know your location, I am providing you with various links to articles on planting and growing potatoes in several US locations. Hopefully, they will help you figure out how to get bigger potatoes.
    https://extension.umn.edu/vegetables/growing-potatoes
    http://www.gardening.cornell.edu/homegardening/scenec6be.html
    https://www.canr.msu.edu/uploads/files/growingpotatoes.pdf
    https://extension.usu.edu/yardandgarden/research/potatoes-in-the-garden
    https://sfyl.ifas.ufl.edu/lawn-and-garden/potatoes-home-garden/
    https://www.johnson.k-state.edu/lawn-garden/agent-articles/vegetables/growing-potatoes.html
    https://extension.colostate.edu/topic-areas/yard-garden/potatoes-in-the-home-garden-7-617/
    https://extension.umd.edu/resource/potatoes

  14. I wasn’t sure about some recent Yellow potatoes so I soaked them in cold water for a few hours and they firmed right up.

    = slight Dehydration & not spoilage!

    Trimming the sprouts and peeling them, these also looked and smelled very fresh and excellent and were also extremely good when boiled.

    Thanks for the good info!

  15. Hi Marlene,

    I have some potatoes that I had bought last year to grow and forgot about them. Now they have sprouted and have green leafy sprouts but the potatoes are gone very soft and mushy when I touched them. Are these still okay to grow? I am thinking that they have gone rotten. I had stored them in my shed that was very hot and am thinking this cause it. I look forward to your kind reply.

    Regards
    Jerusha.

  16. Jerusha, if the potatoes are not rotten, you may be able to still use them; whether they will grow potatoes, is uncertain. However, you have nothing to loose except your time and garden space to try. In a very short time (two weeks or less), you will be able to tell whether they will be viable. The attached publication may be useful if you are new to potato gardening. >>>> https://extension.uga.edu/publications/detail.html?number=C1011&title=Home%20Garden%20Potatoes

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