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What is Solanine and Why Does it Turn Potatoes Green?


Green potatoes with elevated levels of Solanine

Green potatoes with elevated levels of Solanine.

What is Solanine?

Solanine is a poisonous substance that occurs naturally in potatoes and other members of the nightshade family, such as tomatoes and eggplants. A very small amount of solanine can be toxic, and in very large doses it can be fatal.

Signs of Solanine:

In potatoes, the skin will turn green and there will be a very bitter flavor. Symptoms of solanine poisoning include diarrhea and vomiting.

[Also see: Food Poisoning Symptoms]

Preventing Solanine Poisoning:

One of the triggers for solanine to develop in a potato is exposure to light, especially fluorescent light. Therefore, it's always best to store potatoes in a dark place, preferably between 50°F and 65°F. If potatoes must be stored in a lighted place, it's best to keep them in a brown paper bag loosely closed to allow for air circulation.

Dealing with Solanine in Potatoes:

If green discoloration is seen on a potato, the green areas can be cut off, but for safety's sake, it's probably best to discard the whole thing. Deep-frying a potato in oil that's hotter than 320°F will render the solanine harmless.

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