Do Walnuts Go Bad?

Do walnuts go bad? Walnuts are packed with omega-3 fatty acid, an antioxidant that protects healthy cells from oxidative stress. Unfortunately, since walnuts are loaded with oil, these are likely to go bad much more quickly than some nuts. Generally, walnuts are sold with their shells and without their shells. The shelled walnuts are often sold halved, chopped, sliced, or ground into a coarse powder.

Image used under Creative Commons from Pascal Volk

Walnuts without their shells have a shorter life compared to walnuts with their shells intact. Since there is no protective barrier that keeps the elements away from the nuts, shelled walnuts will turn rancid much more quickly. Chopped and ground walnuts have a limited shelf life, just like roasted shelled walnuts so these products will require proper packaging prior to storage too. So how do you store walnuts properly? Continue reading below to find out:

How to Store Walnuts?

Storing Walnuts in the Pantry

For walnuts with their shells on or unopened packs of shelled walnuts, you may keep these products in the pantry. However, due to the nuts’ high oil content, walnuts should be kept in a cool, dry, and dark place away from sources of heat, humidity, and light. Unstable temperatures, sources of heat, and exposure to direct sunlight could cause the oils within the nuts to oxidize, leading to rancidity.

When storing walnuts with their shells on, you can store the nuts in a brown bag. The brown bag keeps the air circulating, which will inhibit mold growth. For unopened packs of shelled walnuts (or with their shells removed), no additional prep needed to store these products in the pantry. This method is best for storing walnuts for short-term.

Storing Walnuts in the Refrigerator

For opened and unopened packs of roasted, chopped, sliced, ground, or halved walnuts, the fridge is one of the best places for short and long-term storage. Walnuts with their shells on could be stored in the fridge as well. The temperature is just right to minimize oil rancidity. However, the moist air may cause the chopped, roasted, sliced, or halved walnuts to soften. If the packs of walnuts are unopened, there is no need to transfer these to another container. For opened packs of walnuts, just keep the opening sealed at all times to retain their freshness.

Storing Walnuts in the Freezer

Is it worth freezing walnuts? If say, you have packs of walnuts that you simply cannot use right away, it is worth freezing the nuts for long-term storage. However, it is best to buy unshelled walnuts for long-term storage. The freezing temperature has a way of altering the original texture of the nuts.

To freeze walnuts, use an airtight container. The container must protect the unshelled nuts from frost and freezer burns. If you are freezing a sizable batch of walnuts, split the batch into serving portions. This way, you do not have to thaw the whole batch if you only need a handful of nuts.

Image used under Creative Commons from Marco Verch

Shelf Life of Walnuts

The shelf life of walnuts will depend on two things: the way the nuts were prepared and the best-by-date. Generally, open bags of unshelled walnuts will keep for at least a month in the pantry. Unopened packs of unshelled walnuts will keep for at least 6 months at room temperature. In the fridge, walnuts will keep for at least a year. When frozen, shelled and unshelled walnuts will keep for at least 2 years. The nuts will keep indefinitely when the temperature is kept at a steady 0 degrees Fahrenheit.

How to Tell if Walnuts Have Gone Bad

It’s easy to tell if the walnuts are no longer safe to use, just give the nuts a whiff. Walnuts have a mild nutty aroma. If the nuts have developed an off odor, like used cooking oil, the walnuts have turned rancid. If the nuts’ once sweet, creamy flavor became bitter, the walnuts have gone bad. Always keep an eye out for mold growth. Walnuts are prone to mold growth due to their high oil content. If you are seeing specks of bluish grey all over the nuts, discard the product right away.

Summary

Do walnuts go bad? Walnuts make a terrific snack or as ingredients in desserts, baked goods, salads, casseroles! But just like most nuts, walnuts won’t keep forever. Always keep all the storage tips we’ve outlined above to extend the shelf life of walnuts, shelled or unshelled!