Have you ever forgotten about the bag of potatoes you left in the back of your pantry and wondered if they are still good to eat? Learn how long potatoes last and how to tell if your potatoes have gone bad. Plus, glean tips for how to store potatoes so they stay fresh as long as possible.
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While many rotten potatoes are easy to recognize (they'll be a dark, moldy, mushy, smelly mess), sometimes you may not know if a potato is still usable without peeling off the skin first. And the shelf life of whole potatoes can vary, depending on how they are stored after purchase. But there is one simple, surefire method for storing potatoes so they'll last for weeks. Read on to find out more.

How Long Do Potatoes Last?

Generally, potatoes last one to two months when stored in a cool, dry, dark and well-ventilated space (never under the sink!), such as the pantry, versus one to two weeks in the refrigerator, according to FoodSafety.gov's FoodKeeper app, the federal consumer resource for food safety.

The United States Potato Board notes that storing potatoes at "colder temperatures lower than 50 degrees, such as in the refrigerator, causes a potato's starch to convert to sugar, resulting in a sweet taste and discoloration when cooked." So, you may want to avoid the fridge and freezer when it comes to storing raw potatoes.

However, If you do store raw potatoes in the freezer, they may last up to 10 to 12 months (more on storing potatoes later). To avoid a sweeter flavor and discoloration, blanch potatoes before refrigerating or freezing. Blanching will also cut down on cooking time after the potatoes have thawed and come to room temperature. (Learn how to freeze potatoes to save time and money.) 

A mix of different potatoes on a designed background
Credit: Getty Images / Brian Hagiwara

4 Signs Your Potatoes Have Gone Bad

There are some obvious signs your potatoes have gone bad, like when they have shriveled, saggy and severely wrinkled skin, and a soft and mushy texture. You know to toss those sad little tubers out. Here are four more, slightly less obvious signs of spoilage. 

1. Mold

It may go without saying, but you do not want to eat moldy potatoes. Potatoes with mold will have black fuzz, sometimes appearing as small black spots, on the skin. It is best to discard moldy potatoes because mold spores are not visible to the naked eye, so it is impossible to discern whether or not you have removed all mold from a given potato. Ingesting mold can make you sick, according to the USDA, most often experienced as mild food poisoning.   

2. Foul smell

Don't let a potato's appearance deceive you. Sometimes, the freshest-looking ones may have gone bad. Use your nose to spot the differences between fresh and spoiled potatoes. The former have an inviting earthy and starchy aroma, whereas the latter give off a musty and moldy odor.

3. Potatoes with sprouts

When you see sprouts or visible bumps and "eyes" growing on potatoes, they indicate that the tubers are getting close to spoilage. While you may be tempted to eat firm potatoes with sprouts by peeling off the skin and cutting and removing the sprouts and eyes, you are better off tossing them out.

When you eat sprouted potatoes, you will likely also eat the naturally occurring compounds, glycoalkaloids, which gives the spuds a bitter taste. These compounds could make you feel sick, causing headaches, diarrhea, vomiting and more when eaten in large amounts.

4. Green potatoes

Like sprouted potatoes, potatoes showing green tinges under the skin warrant a close look as you choose, prepare and eat them.

The greenish hue suggests the presence of nontoxic chlorophyll, due to the tubers being exposed to light. That color also indicates an excess concentration of solanine, a naturally occurring glycoalkaloid. Like sprouted potatoes, when you eat green potatoes in large amounts, you may experience solanine poisoning, leading to unpleasant gastrointestinal symptoms, headaches and more for 8 to 10 hours after consumption.

Since solanine also accumulates under the potato skin, the USDA recommends peeling it off and removing the sprouts and any visible green flesh. Still, your safest bet is to discard these potatoes entirely. 

What If My Potatoes Are Bruised? 

When you peel a potato, you may find darkened or black areas. We're accustomed to cutting them out and continuing with our cooking preparations. That is totally fine. When a potato is free of the spoilage signs listed above, those black areas are bruises the tuber has incurred during some part of the harvesting, transporting and shelving processes. According to the Idaho Potato Commission, "internal bruising happens when potatoes are dropped more than six inches, or if something heavy is placed on top of them. The amount of bruise is directly related to the fall. It can appear beneath the surface of the skin, or penetrate deep into the tuber. The damage does not appear immediately, but becomes noticeable after one or two days in storage. Since the skin is not broken, the damage may not be found until the potato is cut."  

How to Choose the Freshest Potatoes

Fresh whole potatoes are firm to touch with no discoloration and sprouts. However, sometimes you may have to use your sight, smell, touch and taste to spot the differences between the perfect-looking spuds and those on the verge of spoilage.

How to Store Potatoes

In the pantry—away from light, moisture and fluctuations in temperature—whole potatoes will last longer stored in loose plastic or paper bags with holes, allowing air circulation. Check on your stored potatoes regularly to spot any signs of spoilage. Rotten spuds could ruin your batch of fresh potatoes when they are not removed. 

Storing potatoes in the fridge or freezer could significantly increase the formation of acrylamide—a naturally present compound in plant-based foods—when they are eventually exposed to the heat of cooking. Eating large quantities of acrylamide may increase cancer risk. So, soaking raw potato slices in water for 15 to 30 minutes and then draining and blotting them dry before cooking reduces acrylamide formation.

Pantry storage is by far the easiest and best way to go for potatoes. Just be sure to never wash your potatoes before storing them, as the excess moisture could hide in the dimples of the skin and foster mold growth. Wash your potatoes when you are ready to prep them for cooking. 

Bottom Line

Although you can refrigerate or freeze potatoes, the best method, by far, for storing them is in your pantry, where they may last up to two months. Use all your senses when choosing potatoes. Steer clear from those that are moldy, with sprouts, greenish or emitting strange odors. Potatoes should smell fresh and earthy, just like potatoes.

Now that you know you may have one to two months to use up your stash of potatoes, get cooking! Try this delicious recipe, Parmesan Scalloped Potatoes with Spinach, or one of these quick and easy potato dishes: Garlic-Parmesan Melting Potatoes or Ground Beef & Potatoes Skillet.