How to Tell if Chestnuts Are Bad? [Plus Best Ways to Store]

Chestnuts are a delicious addition to many fall dishes due to their subtle, buttery sweetness and creamy texture. However, their shiny outer shells can make it difficult to tell how fresh they are on the inside.

Everybody who is familiar with chestnuts knows the frustration of having a few spoiled chestnuts inside their freshly purchased bag.

The thought of this may make it seem like a hopeless endeavor to find a bag of fresh chestnuts. But, fear not – there are ways to tell if your chestnuts are fresh before and after taking them home from the grocery store!

It’s important to understand what chestnuts are in order to know how to best store them.

Chestnuts are tree nuts that come from certain beech trees and shrubs in North America, Europe, China, and Japan. They grow in clusters inside of large, hard, spiny pods, with one side rounded and the other flat, due to being packed together so tightly. Chestnuts have a deep brown color, with a hard shell and a rather soft interior. They are best stored in cooler climates, such as the fridge or the freezer, which helps to prevent bacteria and other pathogens from spoiling the nut inside.

In this article, we’re going to explore ways to tell how fresh a chestnut is and how you can ensure that yours are fresh.

How to Tell if Chestnuts are Bad

When fresh, chestnuts are firm, shiny, and blemish-free. They are a dark brown color without any discoloration. The inner nut becomes sweet, soft, and creamy after being cooked. However, they are prone to spoilage and can develop fuzzy mold, discoloration, and a hard, brittle texture.

The Shell

Your first clue on whether or not chestnuts have gone bad is how the shell looks. It should be firm, smooth, brown, and rather shiny.

While small blemishes may be purely cosmetic and not harmful, if you see any deep cuts, soft spots, or suspicious discoloration, this is a good indicator that your chestnut may be past its prime.

Float Test

When placed in water, a good chestnut should sink to the bottom. If it floats, then this means that there is extra air inside, which is a potential breeding ground for pathogens.

However, this test is not foolproof and there is a chance that it is still perfectly edible, so make sure to open it up and check for mold or discoloration before tossing it.

See What’s Inside

Sometimes you’ll open up a chestnut and see the dreaded green, fuzzy mold. The nut itself is actually coated in a slightly fuzzy skin, so use discretion when deciding if it’s mold or normal chestnut fuzz.

If it’s normal, it should be tan in color. However, if it’s green, blue, black, or any other color, it’s most likely mold. When in doubt, it’s best to toss the chestnut and move onto the next one to avoid eating a spoiled nut.

Check the Nut Itself

The nut should be plump and have a slight give. You should also be able to break it apart with your fingers relatively easily, which will reveal a light tan color on the inside. If it’s dry, shriveled, brittle, and/or hard, then it has gone bad.

Use Your Nose

Chestnuts should have a mildly sweet, pleasantly roasty smell when they are fresh. The smell should be subtle and not at all overpowering. However, if you open up a chestnut and are met with a repugnant or rotten odor, then throw it straight in the trash.

One Bad Chestnut Does Not Ruin the Bunch

There are usually one or two chestnuts that have spoiled in a bag of chestnuts. But, that does not mean that the rest are bad, as well! Most of the chestnuts should be perfectly usable. Just make sure to check each one individually before using it.

How to Store Chestnuts

Storing chestnuts properly is the best way to prevent spoilage. This is especially important with chestnuts because they tend to be rather pricey. Remember that cooler temperatures will yield the longest life for your chestnuts.


If you are planning on using them within three to four weeks, store uncooked chestnuts in the fridge in a plastic container with some air circulation. A slightly opened Ziploc bag will do the trick. If you have cooked chestnuts, they will last in the fridge in their shell for a few days.


If you are buying in bulk and need to store some for longer periods of time, soak them in water and thoroughly dry them.

Then, place them in a freezer-safe container and store them for up to six months in the freezer. They can be stored cooked or uncooked, and in their shells or out.

Can You Eat Raw Chestnuts?

There are certain species of chestnuts from Asia that can be eaten raw, but chestnuts from Europe and North America contain larger amounts of tannic acid.

This can cause various gastrointestinal issues such as nausea, liver damage, and overall irritation in the stomach, so it is best to cook them before eating. They also tend to have a bitter taste when eaten raw, whereas cooking them brings out their sweet, buttery flavor.

Raw Brown Chestnuts
Raw Brown Chestnuts

How to Cook Chestnuts

Chestnuts can seem intimidating to cook, but they are actually quite easy. Before cooking, make sure to clean them thoroughly by soaking them in water for about 15 minutes and then draining.

Roasting and boiling are the two most common methods. Keep in mind that boiling takes about half an hour longer than roasting.

Roast (Oven or Air Fryer)

Preheat your oven or convection oven to 425°. After washing the chestnuts, use a sharp knife to carve an ‘X’ into the round side of each chestnut. This keeps the chestnuts from exploding due to internal pressure while cooking, and it makes peeling them a breeze.

Place them on a baking sheet and stick them in the oven for about 15-20 minutes, or until the skin around the ‘X’ starts to pull away and the nuts start to feel tender.

Then, wrap them in a thick towel and squeeze until you hear a crackling sound. Once they have cooled, you can peel them and they are ready to eat.


After cleaning, carve an ‘X’ into the round sides of the chestnuts with a sharp knife. Carefully submerge them in a pot of boiling water and let them boil for around 45 minutes, or until the nuts are soft and tender. Drain them, and peel their shells.


After washing and carving the ‘X’ into the chestnuts, arrange them in a microwaveable pie plate, or something similar. Microwave on high for 3 minutes and then in one minute increments after until the chestnuts are nice and soft. Peel and enjoy when cool.

After Cooking and Peeling

After you have properly cooked and peeled your chestnuts, there are many ways to enjoy them! You can eat them right out of the shell, or add them to your favorite Thanksgiving stuffing or dressing recipe. They are great additions to rice dishes, stir fries, soups, and stews.

They are also delicious in desserts. You can chop them, glaze with honey, and top ice cream with them for a unique sundae. Or, you can replace the nuts in cakes, cookies, breads, and pies with chestnuts. They are delicious and versatile, so have fun with them!

What About Water Chestnuts?

Contrary to their name, water chestnuts are not actually chestnuts at all. They are actually aquatic vegetables native to Asia and Oceana. You can most often find them canned and they are used in all different cuisines of Asian cooking.

Unlike regular chestnuts, water chestnuts have a very different flavor and texture. Instead of smooth and creamy, they are crunchy and watery, almost like the texture of an Asian pear or jicama. Their flavor is relatively mild, but they have a light sweetness and nuttiness.

Water chestnuts
The Chinese water chestnuts

How to Tell if Canned Water Chestnuts are Bad

Although canned food rarely goes bad, it is important to be able to tell if any spoilage has occurred.

Canned water chestnuts are usually good for around 3-5 years, but under certain circumstances, can spoil early. Look for signs of discoloration, an “off” smell, or slimy texture.

Check the Can for Damage

Dents or other signs of breakage, especially if on the can’s seam, mean that the can might be punctured, which allows air and pathogens in and compromises the sterility of the can. If you pick up a can of water chestnuts and see that it is damaged, put it back and find another.

Check for Mold

If you open the can and find that mold has formed, discard the food immediately. Mold is always a potential sign of spoilage. Although there are some foods that are safe to eat when the mold has been cut away, water chestnuts are not in this category due to their soft and porous flesh.

Smell Them

Water chestnuts should have a mild odor. If you open your can and find that it has a strong odor, it is best not to use them. Even if it just smells “off”, use your instincts. Remember, it’s better to be safe than sorry!

Check the Color

Water chestnuts should have a uniform light cream color. Brown water chestnuts or anything darker than a light yellow should be thrown away, or at least treated with caution.

Sometimes they will even take on a slimy look or feel, which will alert you that the vegetable has turned.

A Great Fall Food

Remember to get chestnuts in the fall to early winter months when they are in season. This will reduce your risk of taking home bad chestnuts. Chestnuts are a wonderful and healthy addition to your diet.

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