When Should You Not Eat a Russet Potato?

November 11, 2025 •

4 min read

According to the National Capital Poison Center, eating potatoes that have turned green can lead to digestive issues due to a build-up of the toxic compound solanine. It is important to know the signs of spoilage to determine when you should not eat a russet potato, ensuring your meal is safe and healthy.

Quick Summary

This guide details the definitive signs indicating when a russet potato is unsafe to eat, including green coloring, softness, sprouts, and mold. It explains the health risks associated with spoilage and provides proper storage instructions to prevent food waste.

Key Points

Green Skin: Avoid russet potatoes with green skin, as it indicates a buildup of the toxin solanine, which can cause illness.
Soft and Mushy Texture: Discard any potato that feels soft, mushy, or wrinkled, as these are signs of rot and spoilage.
Visible Sprouts: While small sprouts can be trimmed, potatoes with extensive sprouts should be thrown away, as sprouts contain high levels of toxic glycoalkaloids.
Visible Mold: Never eat a potato with mold, even if you cut the moldy portion off, because invisible spores may have contaminated the entire potato.
Foul Odor: A musty, moldy, or unpleasant smell is a sure sign of spoilage and means the potato should be discarded.
Keep it Dark and Cool: Store potatoes in a cool, dark, and dry place with good ventilation to prevent them from turning green or sprouting.
Separate from Other Produce: Store potatoes away from onions and certain fruits to prevent them from spoiling faster due to released gases.

Recognising the Signs of Spoilage

Determining when a russet potato has gone bad is a matter of visual inspection, touch, and smell. A fresh russet potato is firm with a tight, earthy-smelling skin. Any deviation from this fresh state should be a warning to inspect it more closely. Several clear indicators suggest a potato is no longer safe for consumption.

Green Skin and Solanine

A green tint on a potato's skin or flesh is a significant red flag. This color comes from chlorophyll, which is harmless, but its presence indicates that the potato has been exposed to light. This exposure also triggers the production of solanine, a toxic glycoalkaloid that concentrates in the skin and just beneath it. Consuming high levels of solanine can cause digestive upset and other neurological symptoms. While small, lightly greened spots can sometimes be peeled away, it is safer to discard a potato that is significantly green or tastes bitter. Young children are particularly susceptible to solanine poisoning, so green potatoes should never be fed to them.

Softness and Wrinkled Skin

As a potato ages and begins to spoil, it loses its firm texture and moisture. If a russet potato feels soft, mushy, or spongy to the touch, it is past its prime and should be discarded. The skin may also appear wrinkled, shriveled, or saggy. These physical changes are clear signs of decomposition and an indication that the potato is no longer edible.

Sprouts or 'Eyes' and Glycoalkaloids

Sprouts, or 'eyes,' on a potato are a sign of impending spoilage. Sprouts contain high concentrations of glycoalkaloids, including solanine, which can cause illness. If the potato is still firm and the sprouts are small, they can be removed by cutting them away, along with the surrounding area. However, if the potato is also soft, shriveled, or has long, extensive sprouts, it is best to throw the entire thing out. As a potato continues to sprout, it expends its energy, becoming depleted of nutrients and moisture, resulting in a less-than-desirable taste and texture.

Mold and Foul Odor

Visible mold, which can appear as black fuzz or spots, means the potato is contaminated and must be discarded immediately. Cutting off the moldy part is not sufficient, as mold spores can spread and contaminate the entire potato. Furthermore, a musty, earthy, or foul smell is a reliable indicator of rot, even if no mold is visible. A perfectly good-looking potato might smell bad if the spoilage is internal, so always trust your nose.

Comparison of Edible vs. Unsafe Russet Potatoes


Feature	Fresh and Edible Russet Potato	Spoiled and Unsafe Russet Potato
Texture	Firm and solid to the touch.	Soft, mushy, or spongy.
Appearance	Tight, blemish-free skin with a uniform color.	Wrinkled, shriveled skin with dark spots, bruises, or visible mold.
Color	Light brown, consistent skin color.	Greenish tint on the skin or flesh, especially when exposed to light.
Sprouts	No sprouts or small, recently formed 'eyes' that can be removed.	Long, extensive sprouts that indicate high glycoalkaloid levels.
Smell	Mild, earthy aroma.	Musty, moldy, or foul odor.

Proper Storage to Prevent Spoilage

To maximize the shelf life of russet potatoes and avoid food waste, proper storage is key.

Keep them cool and dark: Store potatoes in a cool (around 45–55°F), dark, and dry place, such as a pantry, cellar, or cupboard. Exposure to light increases chlorophyll and solanine production.
Ensure good ventilation: Use a paper bag, mesh bag, or open basket for storage to allow air circulation. Avoid storing potatoes in an airtight container or plastic bag, as this traps moisture and accelerates spoilage.
Separate from other produce: Never store potatoes next to onions or fruits like apples and bananas. These items release ethylene gas, which can cause potatoes to sprout and spoil faster.
Avoid refrigeration: Do not store raw potatoes in the refrigerator. Cold temperatures convert the potato's starch into sugar, affecting its taste and causing discoloration when cooked.

Conclusion

Discarding a spoiled potato is a simple but important food safety practice. By paying close attention to visual cues, texture, and odor, you can easily determine when you should not eat a russet potato. Always remember that signs like green skin, softness, extensive sprouting, and mold are clear indicators to avoid consumption. Proper storage is the best defense against premature spoilage, ensuring that your meals are not only delicious but also completely safe. Following these guidelines helps protect your health and makes the most of your food. For more detailed information on food safety, you can consult reliable sources such as the USDA.

Frequently Asked Questions

If a russet potato has only a small amount of green skin, it may be safe to peel away the green portion and the area just beneath it. However, if the potato is significantly green, or if the flesh beneath the skin tastes bitter, it should be discarded entirely due to high solanine levels.

You can eat a russet potato with small sprouts, but you must cut them off completely along with the surrounding area. If the potato is soft, shriveled, or has long, extensive sprouts, it should be thrown out, as its nutritional value is diminished and glycoalkaloid levels are higher.

Eating a spoiled russet potato, especially one with high levels of solanine from greening or sprouting, can cause gastrointestinal and neurological symptoms like nausea, vomiting, diarrhea, headaches, and abdominal pain. In severe cases, solanine poisoning can be more serious, so it is best to avoid the risk entirely.

No, you should not refrigerate raw russet potatoes. Cold temperatures convert the potato's starch to sugar, which affects its taste and can cause discoloration when cooked. A cool, dark, and dry pantry is the best storage location.

A foul, musty, or moldy odor often indicates internal rot or mold. Even if the exterior looks fine, a strong bad smell is a reliable sign of spoilage, and the potato should be discarded.

It is not recommended to store russet potatoes with onions. Onions release ethylene gas, which can accelerate the sprouting and spoilage of potatoes. It is best to keep them separate in a well-ventilated area.

When stored properly in a cool, dark, and dry place with good ventilation, raw russet potatoes can last for several weeks to a few months. Storing them in a cardboard box can help them last even longer.