Do Walnuts Go Bad? See What You Didn’t Know About Your Favorite Nuts

Nuts are known for their long shelf life. However, they still go bad. Walnuts are one of those nuts that last several months retaining their quality.

But when you do not keep your walnuts well, they go bad and taste unpleasant. If you have tasted a bad walnut, you will agree that it can mess up your palate.

Although walnut will naturally last long, you should know how long, how to identify bad walnuts, and how to preserve them from spoilage.

What are walnuts?

Walnuts are edible seeds that grow from the walnut tree. These trees grow in many countries in the world, which is why they are very versatile.

Walnut is rich in fiber, protein, and fatty acids which have great nutritional value. Eating walnut provides your body with antioxidants that increase resilience against oxidative damage.

These nuts also have the potential to reduce one’s risk of getting diseases like cancer, heart problems, and diabetes. Additionally, the high fiber content in walnuts can help control weight gain.

Furthermore, walnut is most often eaten raw or cooked as a snack on the go. But it is also good in dishes. You can add walnut to salad, pasta, sandwich, yogurt, and as a coating for fish or chicken.

Do walnuts go bad?

Yes, walnut goes bad.

The nuts have a long shelf life but different factors influence how long your walnuts last and retain their quality.

How you store the walnuts (shelled or unshelled) and where you store them determines how long they last.

Additionally, despite their long shelf life, walnuts go bad because their nutritional composition includes oils and fatty acids that make the nuts oxidize quickly and go rancid.

Therefore, you need to know all these and store the nuts properly to prevent this.

Do walnuts go bad in the shell?

Unshelled walnuts do not go bad, at least not quickly. The shell is a protective covering that shields the kernel from external factors that can make the walnut go off.

Unshelled walnut last twelve months if you keep them properly at room temperature. Walnut may last longer than twelve months if the weather condition is favorable.

You can expect the nuts to last longer if you store them in a refrigerator or freezer. However, the longer you store unshelled walnut, the more the number of rancid nuts you will get when you are ready to use them.

Do shelled walnuts go bad?

Shelled walnuts are more exposed to spoilage because the shell that covers the nuts is no longer there.

Walnuts without their shells will last only three weeks in an airtight container at room temperature.

In addition, if you choose to store them in a refrigerator or freezer, you can enjoy walnut of good quality for 6 months up to a year.

Do walnuts go bad in the fridge?

Walnut keeps longer when you store them in the fridge. Shelled walnut can last up to six months in the fridge if you store them in an airtight container or freezer bag.

Proper packaging before refrigerating will help to keep out moisture and keep the nuts fresh.

Do walnuts go bad if frozen?

Freezing is the best way to preserve walnut long-term. With proper packaging and sealing, walnut should taste fine even after thawing.

Do not freeze ground or chopped walnut. Freeze the nuts whole and process them when you are ready to make use of them.

Do chopped walnuts go bad?

Chopped walnuts have a very short lifespan. Freshly chopped walnut will last a few hours to one day on the kitchen counter. But, if you refrigerate it, you can preserve it for about a month.

Keep the chopped nuts in an airtight container, away from other foods that can trigger spoilage.

Do roasted walnuts go bad?

Roasted nuts go bad after exposure to air and moisture. Moreover, because they are nuts anyway, they go rancid after a few hours. Roasted walnut will last only a few hours if you leave them in the open.

You can expect roasted walnut to last two weeks if you store them in an airtight container. The nuts keep better and longer if you refrigerate them.

Do candied walnuts go bad?

Yes, they do.

Candied nuts will go bad after some days, depending on how you preserve them. The nuts keep well for 1-2 weeks at room temperature and up to a month if you keep them away from air and sunlight.

What is the shelf life of walnut?

The shelf life of walnut varies with how they are stored.

  • Whole (unshelled) walnut has a shelf life of 12 months anywhere they are stored
  • Shelled walnut can last up to 3 weeks in an airtight container in the pantry, 6 months in a refrigerator, and 12 months in a freezer
  • Processed (chopped or ground) walnut will keep for 1 day at room temperature. If you refrigerate them, you can have your nuts around for up to one month. Freeze them to enjoy processed walnut for up to 6 months

Can you eat bad walnut?

Eating expired nuts may not threaten your health, but it is not good either.

You risk GIT problems if you eat bad walnut. Also, the awful taste of bad walnut can spoil your palate for a few hours.

How to tell if walnut is bad

Examine the shell

If the shell of the walnut looks dried out and shrunken, the nut in it is most likely rancid. Crack the shell open and examine the nut.

A dried-out nut, a nut with net formation, or the presence of organic growth are signs that the nuts are not fit for food anymore.

Touch the nut

Good walnut feels firm in the hands; this is something bad nuts do not have. A bad walnut will feel slimy or slippery. If you notice this, you should toss the nuts away.

Mold growth

You may not observe mold growth on the shell of a walnut. This is another reason you should break your walnut and look at the inside before you eat it.

Mold growth on walnut appears as dark spots on the nuts. Discard nuts that show this sign.

An off smell

A good walnut has a slight aroma, but when they go bad, they smell rancid.

A rancid walnut smells like oil. And this is a result of the oxidation of natural oils and fatty acids present in the nuts.

Taste the nuts

If you are not so sure about the quality of the walnut after examining the appearance and taking a whiff, take a bite. Bad walnut is bitter and tastes awful. Discard nuts that taste like this.

How to preserve walnut

  • For long-term storage, keep walnuts unshelled until you are ready to use them
  • Store shelled, chopped, and ground walnut in the fridge or freezer
  • Also, keep unshelled walnut in an airtight container and far away from foods with strong smells like onion
  • In addition, walnut should be kept in a cool, dry place like the pantry
  • For long-term storage, freeze the walnuts


Why do walnuts go bad so quickly?

Walnuts go bad quickly because of the high content of polyunsaturated fatty acids and oils that make them oxidize quickly and go rancid.

Can you get poisoned by raw walnut?

Yes, you can.

Common side effects of eating raw walnuts, especially black walnuts, are signs of food poisoning.

Raw walnuts contain harmful bacteria that can lead to salmonella poisoning but it is not likely to result in a serious illness.

Why do you feel nauseated after eating walnuts?

A nauseous feeling after eating walnuts is a sign of nut allergies.

Should you wash walnuts before eating them?

Yes, you should. Walnuts contain harmful bacteria that can cause food poisoning. Washing the nuts help to get rid of the bacteria.


Walnuts are a rich source of folic acid, omega-3 fatty acids, and antioxidants. They are very nutritious and can help improve the appearance of your skin.

Walnuts have a long shelf life, but how long they last depend on how well you store them.

Generally, unshelled walnuts last longer than shelled walnuts. Store your walnuts in an airtight container. They also keep well at room temperature. But for long-term storage, keep the walnuts in a refrigerator or freezer.

Thanks for reading.

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