Do Nuts Expire? Here's How to Tell if Yours Are Still Good

Between their crunchy texture and delicious flavor, nuts have a lot to offer. They're also packed with protein and healthy fats, making them a nutritious addition to your kitchen. However, there's a lot of confusion around nut storage, and you may wonder if nuts expire or go bad. It doesn't help that different varieties have different shelf lives, depending on where they're stored. We spoke to chefs to get to the bottom of nut expiration and storage, plus how to tell whether your nuts are fresh.

Do Nuts Expire?

The freshness of nuts comes down to their unsaturated fats. These are the "good" fats that make nuts so healthy for you to begin with. "Unsaturated fats are very sensitive to heat, light, and oxygen," says Ann Ziata, chef at the Institute of Culinary Education in New York City. If the fats are exposed to these elements, they will undergo a chemical process called oxidation. Essentially, the fats will break down into smaller, unstable fatty acids, break down into smaller, unstable fatty acids, notes Ziata. As a result, the nuts go rancid or spoil—but they don't necessarily expire.

Typically, the packaging of nuts lists a "best by" date, which indicates when the nuts will have the best quality. Beyond that date, they’re more likely to go bad. And while eating spoiled nuts won't make you sick, the texture and flavor will be undesirable, so it's worth learning how to properly store nuts.

Signs of Spoiled Nuts

If nuts have been stored properly but have become rancid due to age, they will smell a bit sour, explains Ziata. The odor might even be similar to paint. Rancid nuts will also have a soft texture and, if you accidentally eat one, a bitter and sour taste.

If nuts have been improperly stored and go bad, they'll likely have visible mold and moisture, says Ziata. They'll also have a soft, mushy texture in addition to that off-putting smell.

The Best Way to Store Nuts

"If you plan [to use] the nuts in the next couple weeks, you can keep them in the package they came in or in a glass jar in the pantry," says Ziata. Otherwise, for long-term storage, store nuts in a cool, dark part of the pantry or in the fridge, and use airtight, opaque containers to protect them from light and oxygen, notes Ziata. "Storing [nuts] in cooler temperatures will prolong their shelf life as it slows the oxidation process of the oils," explains Nathan Lyon, chef, cookbook author, and host of A Lyon in the Kitchen on Discovery Health.

For storing nuts in the freezer, put them in an airtight glass container. Make sure to pack the vessel as much as possible to limit empty space. Alternatively, you can put the nuts in a freezer-safe resealable plastic bag.

How Long Different Nuts Last

Here are general estimates of how long each type of nut will last, per Ziata and Lyon:

Almonds

• Pantry: 1 year
• Refrigerator: 2 years or longer
• Freezer: 2 years or longer

Pecans

• Pantry: 4 months
• Refrigerator: 6 months
• Freezer: 2 years

Walnuts

• Pantry: 3 months
• Refrigerator: 1 year
• Freezer: 2 years

Peanuts

• Pantry: 3 to 6 months
• Refrigerator: 6 months to 1 year
• Freezer: 1 to 2 years

Hazelnuts

• Pantry: 3 to 6 months
• Refrigerator: 1 year
• Freezer: 2 years

Cashews

• Pantry: 3 to 6 months
• Refrigerator: 1 year
• Freezer: 2 years

Pistachios

• Pantry: 6 months  
• Refrigerator: 1 year
• Freezer: 2 years (in shell), 1 year (shelled)

Macadamias

• Pantry: 6 months
• Refrigerator: 1 year
• Freezer: 2 years