Do Walnuts Go Bad? How Long Do They Last?

logo by Editorial Staff | Updated on August 3rd, 2022

Walnuts are a healthy and tasty snack. But do walnuts go bad? If you store walnuts wrong, they can spoil and turn rancid. 

What Is the Shelf Life of Walnuts?

Unshelled walnuts may be stored in the pantry for up to a year. Of all, it’s not as if all the nuts should be tossed after that period. However, the odds are that some of them will be dried out or stale, and others will be rotten.

white sea shells on white textile

If you purchased a box with a best-by date on the label, you might safely expect that most of the nuts will survive for a few months beyond that date. In short, the longer unshelled walnuts are stored, the more they will become rotten after breaking.

When it comes to walnuts in their shell, it’s reasonable to estimate that they’ll keep fresh for around 6 months in the fridge or at least a year in the freezer.

The longer you keep them, the more of them will grow rancid, just like their unshelled cousins. And rotting walnuts taste harsh, which isn’t ideal for any dish that calls for them.

Walnuts type pantryfridge freezer 
Unshelled 6-9 months 12 months 2 years 
shelled 3 weeks 6 months 1 year

How Long Do Walnuts Last at the Grocery Store?

Remember that you have no clue how old walnuts are when you purchase them at the shop. As a result, it may be difficult to predict how long they will continue.

On the other hand, unshelled walnuts should last around 6 months in the cupboard. They may live considerably longer or go bad much sooner, but this should give you a decent indication of what to anticipate.

Walnuts that have previously been shelled will not survive as long. If kept in a sealed bag or container, they may survive up to a month in the pantry, possibly two.

How Long Can Walnuts Be Stored in the Fridge?

Refrigerating walnuts extend their shelf life significantly. Refrigeration is an excellent strategy to preserve your walnuts kept for a long time.

Unshelled walnuts may be stored in the refrigerator for at least a year. They may last considerably longer or not nearly as long as in the pantry, although they may keep for 18 months or more.

When refrigerated, shelled walnuts have a comparable shelf life. Depending on various conditions, they also have a shelf life of roughly a year, plus or minus a few months.

What causes walnuts to spoil?

Due to their high-fat content, walnuts do not tolerate prolonged exposure to severe conditions. These are the standard components, such as excessive air, wetness, direct sunshine, or heat. These may be prevented by following the storage suggestions we provided above.

Why do walnuts get rancid so fast?

Walnuts go rancid so rapidly because they contain a high quantity of fatty acids, making them more sensitive to oxidation when kept improperly. Other nuts that become rancid rapidly include pistachios and pine nuts, both of which have a high-fat content. The good news is that the oxidation process may be halted by properly storing nuts.

Are unshelled walnuts preferable?

Though unshelled walnuts need much more work to prepare when it comes to putting your dish together, the benefits outweigh the drawbacks. They need very little effort to store and take significantly longer to spoil.

How to Determine Whether Walnuts Are Bad

Fresh walnuts are a treat to eat.

However, biting into a walnut that has passed its prime will leave you with an awful taste on your tongue, and it is an experience you will not want to repeat.

As a result, it is useful to know how to determine if walnut is still edible or whether it has passed its prime.

Take a look at the shell and the nut.

If you have unshelled walnuts, the shell may reveal a lot about the quality of the nut within.

If the shell of your walnut has withered, distorted, or dried out, you should not even attempt to open it since the nut has gone rotten.

However, if the shell seems in good condition, split it open and inspect the nut. You should not ingest the nut if it displays evidence of mold infection, net formation, or organic growth areas.

Furthermore, if the nut seems to be dry or shriveled, it is preferable not to consume it.

Try Smelling The Nut

Walnuts have a great mild and sweet, nutty fragrance.

If your walnut has a rancid odor or smells like frying oil, the oils and polyunsaturated fatty acids have gotten over-oxidized, causing it to be rancid.

You won’t become sick if you eat that nut, but it will be bitter and unpleasant.

Furthermore, consuming nuts that have passed their optimum consumption dates will not offer you the great health advantages they typically provide.

Shake The Nut

When you pick up a healthy unshelled walnut, it is weighty, and when you shake it, you can’t hear the kernel moving within the nut.

When a walnut has gone rotten, it will feel light when shaken, and you can hear the kernel moving about within the shell.

As a result, if you shake your unshelled walnut and hear the nut moving within, it’s time to toss it.

Detecting Whether Chopped Or Ground Walnuts Are Still Safe To Eat

Sift over the nuts if you have chopped or powdered walnuts and want to know whether they are still fresh.

If you see any mold contamination, staining, or discharge, discard the whole bag.

Smell the nuts if they seem to be in good condition. They are still fresh if they have that wonderful nutty aroma. However, if they smell sour, such as paint thinner, it is advisable to avoid eating them.

How to store Walnuts

Keeping walnuts is similar to storing other nuts such as pecans or pine nuts.

Nuts contain a lot of oil, and as you surely know, oil oxidizes. Rancidification may occur due to extended exposure to heated temperatures, temperature fluctuations, moisture, or oxygen. As a result, keeping them typically implies that you are protecting them from these forces.

Walnuts are often offered with or without their shells. Unshelled walnuts keep longer and have fewer stringent storage requirements since the shell acts as a great protective barrier.

Begin with unshelled walnuts. They don’t need to be refrigerated because of the shell. All you have to do is maintain them in a cool, dark spot away from direct sunlight. A dark pantry closet is usually the best solution, although the kitchen may also work.

Wait to shell the walnuts until you need them for the greatest quality.

Shelled walnuts deteriorate significantly faster than unshelled walnuts. If you wish to keep them for an extended amount of time, you should either refrigerate or freeze them.

You may put the walnuts in the fridge as long as the packaging is unopened; no extra wrapping is necessary. Some protection is required if you wish to freeze them immediately away. A sealed freezer bag or an airtight container would suffice.

After opening the packet, place the nuts in an airtight container or freezer bag. This will keep the moisture from the fridge at bay and prevent any unpleasant aromas from entering. The latter is significant since walnuts in their shell tend to absorb strong scents. The same containers are ideal for freezing the nuts.

Last, if you want to chop or ground the nuts, do so shortly before adding the walnut meal to your recipe. This provides the greatest flavor.

Should walnuts be kept refrigerated?

Once a bag of walnuts has been opened, or the shell has been removed, it is preferable to refrigerate them immediately in a sealed container.

By doing so, you can increase their shelf life from 2-4 weeks to a staggering 6 months! This longevity may be prolonged even more by freezing if you so want.

They should be able to keep their quality for up to two years. There is no need to refrigerate walnuts that are still in their shell since they will keep in the pantry and out of direct sunlight for up to a year.

Can walnuts be frozen?

As previously said, if you want to keep the walnuts for a long time, you must keep them in the freezer. So, sure, walnuts may be preserved in the freezer for an extended amount of time. Its shelf life is also extended. They may be stored in the freezer for almost a year.

How to freeze walnuts

Freeze them in an airtight jar with a tight-fitting lid. Before freezing walnuts, place them in an airtight bag or container. An unopened bag of walnuts may be frozen in the bag they arrived in, allowing them to be placed directly in the freezer.

Consider keeping them in different bags. If you don’t intend to use or thaw out all of the walnuts at once, you should keep them in separate bags or containers. In this manner, you may thaw out just what you need and keep the remainder frozen.

Thaw them in the fridge for several hours or overnight. Refrigerate frozen walnuts for at least a few hours to defrost. Consider beginning the day ahead of time and storing them in the refrigerator overnight to prevent hurrying them.


Editorial Staff

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