Green Potatoes: Safe to Eat or Toxic? Understanding Potato Sprouting and Greening
Potatoes turning green or sprouting is a natural process as the tuber attempts to reproduce. This article explores the safety of green potatoes and sprouted potatoes, discussing whether they can be eaten or should be discarded. We’ll delve into the presence of glycoalkaloids in potatoes, proper potato storage methods, and potential risks associated with consuming green or sprouted potatoes.
Green Potatoes: Safe to Eat or Toxic? Understanding Potato Sprouting and Greening
Potatoes turn green and sprout because they’re trying to fulfill nature’s plan for reproduction. Let’s discuss what to do if potatoes turn green: can you eat green potatoes, and is it safe to consume sprouted potatoes, or should they be thrown away?
Glycoalkaloids in Potatoes
Potatoes contain two toxic glycoalkaloids called solanine and chaconine. However, fresh potatoes that haven’t sprouted contain only small amounts of glycoalkaloids in concentrations safe for consumption. Exposure to light significantly increases the formation of chlorophyll and glycoalkaloids.
All parts of the potato plant contain glycoalkaloids. The highest concentration is found in leaves, flowers, “eyes,” green skin, and sprouts. The lowest concentration is in the white body of the potato. Glycoalkaloid formation in potatoes increases with high storage temperatures and light exposure. Cooking potatoes by baking, boiling, frying, or microwaving does not eliminate glycoalkaloids. However, removing the potato skin before cooking can reduce glycoalkaloid content.
Can You Eat Sprouted Potatoes?
When potatoes start to sprout, their growths (roots, eyes, and bumps) contain a high concentration of compounds called glycoalkaloids, which can cause a sharp, unpleasant, bitter taste. You’re unlikely to see any side effects from consuming minor amounts — in fact, one of these compounds, called solanine, is the same compound naturally found in eggplants, tomatoes, and peppers (a class of plants known as nightshades). However, in large quantities, it can be toxic.
Large sprouts, growths, and roots will not only be unpleasant to eat but, in the worst case, can be truly toxic. Symptoms of solanine poisoning (a special type of natural toxin found in spoiled potatoes) include everything from fever and headache to severe stomach upset or abdominal pain. Needless to say, it’s worth going to the grocery store and buying some new potatoes. It’s best not to eat potatoes with sprouts.
Can You Eat Green Potatoes?
What if potatoes have turned green? Potatoes exposed to light will start producing chlorophyll (leading to the green color) as well as solanine. Chlorophyll is responsible for the green color of many plants and is not toxic. However, the green color of increased chlorophyll may indicate an excess of glycoalkaloids in the potato. If the green tint on your potatoes is light and covers less than 10% of the entire tuber, you can eat such potatoes after peeling, but if the potato is entirely green, it may be unsafe.
You can minimize glycoalkaloid toxicity by buying potatoes only as needed and storing them in a dry, cool place. They should be in a breathable container so air can circulate around them. Don’t store potatoes in airtight containers, and don’t store them with onions, as the gases emitted by onions can accelerate potato sprouting. The same advice for preventing any foodborne illness applies to potatoes: if in doubt, throw it out.
According to a study documented in the Encyclopedia of Food and Health, glycoalkaloids may have some health benefits, such as lowering cholesterol or fighting inflammation. But when there are too many of these compounds, they can be toxic.
