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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