When Should You Not Eat Russet Potatoes?

November 4, 2025 •

3 min read

According to the Center for Food Safety, potatoes produce glycoalkaloids, which can be toxic. You should not eat russet potatoes if they are soft, severely green, or have many sprouts, as these indicate spoilage and increased toxins. Checking your potatoes correctly is crucial for kitchen safety and preventing illness.

Quick Summary

Identify unsafe russet potatoes by recognizing signs like softness, green patches, and significant sprouting. Understand the risks of solanine and best practices for safe potato consumption and storage.

Key Points

Softness and Mushiness: A firm russet potato that has become soft, mushy, or wrinkled should be discarded, as this indicates decomposition.
Green Skin: Significant greening on a russet potato signals a potential increase in the toxic compound solanine. While small green spots can sometimes be peeled away, heavily green potatoes should be thrown out.
Excessive Sprouts: Russets with long, excessive sprouts, especially if they are also soft or shriveled, are unsafe to eat due to high levels of glycoalkaloids.
Foul Odor: Any potato with a musty, moldy, or pungent smell is spoiled and should be discarded immediately, regardless of its appearance.
Visible Mold: Mold on any part of the potato means the entire potato should be discarded, as spores can penetrate the flesh.
Proper Storage: Store russet potatoes in a cool, dark, and dry place with good air circulation to prevent greening and sprouting. Avoid storing them in the refrigerator.
Toxins and Cooking: Be aware that cooking, including boiling or frying, does not effectively destroy high levels of solanine in potatoes.
Bitter Taste: If a cooked potato tastes unusually bitter or causes a burning sensation, it may contain high levels of solanine and should not be eaten.

The Dangers of Glycoalkaloids

Potatoes naturally create glycoalkaloids, primarily solanine and chaconine, to defend against pests. In fresh potatoes, levels are low and harmless. However, when damaged, stored incorrectly, or exposed to light, toxin concentrations can rise. High levels can cause solanine poisoning, with symptoms ranging from mild digestive upset to serious neurological issues.

Why Green is a Warning Sign

Greening is a clear sign that a russet potato may have elevated glycoalkaloids. This green color comes from chlorophyll, which indicates the potato has been exposed to light. Since chlorophyll and solanine production are triggered by light exposure, green patches warn of increased toxicity.

Light Greening: If only a small area is green, peel away the skin and green flesh. If it tastes bitter, discard it.
Extensive Greening: If extensively green, discard the entire potato. Cooking does not eliminate the toxins.

When Sprouting Signals Trouble

Small sprouts or "eyes" are a natural part of a potato's lifecycle and don't automatically mean it's unsafe. However, glycoalkaloid concentration is highest in the sprouts and around the eyes. Safety depends on the potato's condition.

Small, Recent Sprouts: Remove sprouts and surrounding eyes completely.
Excessive or Long Sprouts: If the potato has long, well-developed sprouts, it's past its prime. The entire potato should be thrown out.

Other Clear Signs of Spoilage

Beyond greening and sprouting, there are other indicators that a russet potato should not be eaten.

Soft or Mushy Texture: A healthy potato is firm. A soft or mushy texture indicates spoilage.
Foul Odor: Fresh potatoes have an earthy smell. If it smells moldy or pungent, it has gone bad.
Mold: Any visible mold is a definite sign of spoilage.
Severe Bruising or Blemishes: If the potato has large dark spots or the skin is shriveled, it's best to discard it.

Comparison of Safe vs. Unsafe Russet Potatoes


Characteristic	Safe to Eat	Unsafe to Eat (Discard)
Texture	Firm and solid to the touch.	Soft, mushy, or wrinkled skin.
Skin Color	Uniformly brown, with no green patches.	Significant greening on or under the skin.
Sprouts	Small, recently formed sprouts that can be fully removed.	Long, excessive sprouts, especially with soft skin.
Odor	Fresh, earthy, and nutty.	Moldy, musty, or pungent.
Taste	Neutral, starchy taste.	Bitter or causes a burning sensation in the mouth.

How to Prevent Spoilage

Proper storage is the best defense against russet potato spoilage.

Store in a Cool, Dark Place: Keep potatoes in a dark area with good ventilation, like a pantry or cabinet, ideally between 50-65°F. The refrigerator is too cold and can cause starches to convert to sugar, leading to an unappealingly sweet flavor.
Ensure Air Circulation: Do not store russets in an airtight container or a sealed plastic bag. A paper bag, mesh bag, or breathable box is best for allowing air to circulate.
Keep Them Away from Onions: Onions release ethylene gas, which can accelerate potato sprouting. Store them separately to maximize both vegetables' shelf life.
Use First-In, First-Out (FIFO): Use older potatoes before newer ones to maintain freshness.

Conclusion

It's important to be vigilant about the freshness of russet potatoes. Always inspect for spoilage signs, including a soft or mushy texture, green coloring, a foul odor, and excessive sprouting. Following proper storage techniques can extend shelf life and ensure every potato dish is safe and delicious. Discard a potato that shows significant signs of decay. For more information on food safety, you can consult resources like the CDC.

References

Centers for Disease Control and Prevention. Food Poisoning. [https://www.cdc.gov/foodsafety/food-poisoning.html]
Healthline. How Long Do Potatoes Last? Raw, Cooked, and More. [https://www.healthline.com/nutrition/how-long-do-potatoes-last]
Poison Control. Are Sprouted Potatoes Safe to Eat? [https://www.poison.org/articles/are-green-potatoes-safe-to-eat-191]
Yahoo Lifestyle. Six Ways To Tell if a Potato Is Bad (And How to Properly Store Them). [https://www.yahoo.com/lifestyle/six-ways-tell-potato-bad-180000828.html]

Frequently Asked Questions

Yes, if the russet potato is still firm, you can remove the small sprouts and the surrounding 'eyes' with a peeler or paring knife before cooking. However, if the sprouts are long or the potato is soft, it's safer to discard it.

A green tinge indicates the presence of chlorophyll and potentially elevated levels of the toxin solanine. For light greening, peel the potato generously to remove all green flesh. If the greening is deep or extensive, it is safest to throw the potato away.

No, you should never eat a potato that has visible mold. Mold spores can penetrate deep into the potato where they are not visible, making it unsafe to simply cut away the affected area.

Eating spoiled potatoes can cause food poisoning, with symptoms like nausea, vomiting, abdominal pain, and diarrhea. In severe cases of solanine poisoning from highly toxic potatoes, symptoms can be more severe.

No, cooking methods like boiling, baking, and frying do not effectively remove or destroy high levels of solanine and other glycoalkaloids. If a potato is green or excessively sprouted, cooking will not make it safe.

The best prevention is proper storage: keep them in a cool (50-65°F), dark, and dry place with good air circulation. Store them in a paper bag or cardboard box, and keep them away from onions and other produce that release ethylene gas.

Solanine poisoning is an illness caused by ingesting high levels of glycoalkaloids from potatoes. Symptoms can include digestive issues, headaches, and neurological problems. It is a rare but serious condition that results from consuming improperly stored or spoiled potatoes.