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What to Do When the Skin on My Idaho® Potatoes Is Green

Q:

I got a great buy on ten pounds of Idaho potatoes and now I have discovered the skin is green. Are they safe to eat?

A:

Fresh potatoes are really one of the best bargains in the whole produce department, especially per ounce or pound. I am glad to see that you have already figured out several different ways to prepare them for your family. The answer to your most pressing question, can I get sick eating potatoes that have a greenish caste to them, is NO. The greening occurs in nature, and can happen in the fields when a growing potato is exposed to sunlight, typically from a crack in the ground. Our fresh potato shippers sort the potatoes for size and physical defects when they are taken out of storage and almost always catch those with some green on them. These are trimmed of the green and used to make processed potatoes such as French fries, hash browns and instant mashed potatoes. The industry could not use these if there was a food safety problem that affected the whole potato.

The most frequent cause of potatoes turning green is improper storage. Ideally, store your potatoes in the dark so they are not exposed to light, especially fluorescent. It only takes a few days to have the potatoes start to have a greenish outer skin.

Sometimes this happens at the grocery store. If potatoes are not rotated properly, or sales slow or the buyer ordered more to get a good buy.  Then the potatoes may sit out on the display and turn green where the light can penetrate the bag.

There are technical terms for what is happening, basically the potato is producing this green as it is trying to revert back to growing a plant, and it produces chlorophyll which is not toxic. The other substance produced is called solanin, which can be bad if consumed in large quantities. If you are on an all potato diet you might have to be worried about this. The skin will taste bitter so you probably would not consume much of it on purpose.

My advice… peel the potatoes and discard the skin for your mashed and hashbrowns. Discard the potatoes with the green skin for baking purposes or… bake but don’t eat the outer skin.