Do Pistachios Go Bad? All You Need To Know

Written by: Mike Marshall
Updated:

So you’ve scored a great deal on pistachios. 

Now what? 

How to store such a large bulk? Do pistachios go bad fast?

It’s not too late to find out the answers to these questions about pistachios. In this article, we’ll discuss their shelf life, as well as how you can extend it.

Keep reading!

How Long Do Pistachios Last?

Like most nuts, pistachios have a rather long shelf life. When kept at room temperature, they’ll stay fresh for about half a year or so. In most cases, the expiry date on the label will say roughly the same amount of time. 

But if you keep pistachios stored properly, they’ll retain freshness even months past the date on the label. 

According to the University of California, pistachios can be kept in the fridge for about a year. If you plan on keeping them fresh for even longer, then storing them in a freezer is your best bet. At temperatures of 0° Fahrenheit or lower, pistachios will remain edible for up to three years. 

Shelf LifeFridgeFreezer
Pistachios (in-shell and shelled)~1 year~3 years

The shelf life is pretty much the same for both in-shell or shelled pistachios. That’s because ripe pistachio nuts crack open naturally. That means they’re no longer protecting kernels from environmental factors. 

As for the roasted pistachios, they generally have a shelf life of about one-fourth that of the raw pistachios. That’s because the roasting process causes a change in the cell microstructure. It destroys antioxidants naturally found in cells, which protects them from air exposure. What this means is they oxidize at a much faster rate than raw nuts. 

How To Tell If Pistachios Are Bad?

When it comes to spoilage, it’s pretty visible in the case of pistachios. Starting with the color, fresh pistachios are pale green. Then as they start degrading, their color darkens into brown hues.

Over time, the kernel might appear to be dried out and wrinkly. When fresh, pistachios are well-rounded and smooth. But this change in texture doesn’t necessarily mean that your favorite snack is spoiled. 

Pistachios generally start to shrivel when turning rancid. You won’t actually get sick by eating rancid pistachios, but your stomach might not take it too well. 

Mold forming is a clear sign that pistachios have gone bad. If you notice pale, powdery growth on them, they’re only good for garbage. Molded pistachios not only taste disgusting but aren’t safe for consumption. Doing so can cause health conditions much more severe than simple food poisoning.  

Another telltale sign that your pistachios are not safe to eat is seeing insects around the packaging. Weevils, meal moths, and other pantry pests are known to lay eggs inside food containers. The last thing you need is to eat larvae by accident, isn’t it?

These nasty displays of spoilage are unlikely to appear if you store pistachios properly. By that, I mean in a clean and dry pantry, free of moisture and spoiled food. In such conditions, your pistachios will just go rancid. This process results in off-taste and smell.

The best way to check for rancidity is to take a bite of pistachio. If it tastes sour or bitter, it has clearly gone rancid. Harsh flavor can also be accompanied by a strong chemical smell, similar to a nail polish remover. 

How To Store Pistachios

pistachious in a bowl

Pistachios are not as prone to rancidification as some other types of nuts. That’s mainly because pistachios have a much lower oil content than, for instance, almonds and walnuts. Still, keeping them in a warm and humid environment will cause faster degradation.

Like other nuts, pistachios stay fresh longer when stored at cold temperatures. A cool environment is a great way to slow down the rancidification process and keep pistachios fresh for longer.

In case you’re keeping them in the fridge, it’s really important to store them in a proper airtight container. Otherwise, pistachios will pick up odor from other food in your fridge. Surely, you don’t want your favorite snack to smell like fish, do you?

Keeping them in a freezer will allow you to extend their shelf life even further. In theory, you could keep them fresh for as much as two years. But after such a long time of being frozen, the nutritional value of pistachios will be compromised.

As we already mentioned, pistachios can last up to six months when kept at room temperature. Let’s say you plan on going through an entire stock of pistachios in a short amount of time. Then, storing them in your pantry or the cabinet is the way to go. 

But you don’t want to keep them in a bowl. When exposed to air for too long, they’ll start degrading at a much faster rate than usual. 

Store-bought pistachios usually come in a bag, either paper or plastic. These packaging options don’t do much to keep pistachios safe from air and moisture. If you don’t plan on eating the whole bag in one go, you should definitely change the packaging.

Whether you store pistachios in the pantry or the fridge, the same rule applies. The only way to protect pistachios from oxygen and moisture damage is to use an airtight container or a releasable bag.

In case you own a vacuum sealer, even better. You can use it to store away a stack of pistachios you don’t plan on opening up any time soon.

When it comes to containers, your choice of material matters. Plastic containers are cheap, but they don’t stay sealed as well as other containers do. 

Glass or ceramic containers are both better options for storing pistachios. You can also use metal ones, as long as they’re not made of aluminum. Stainless steel is a good choice of material for food packaging.  

Finally, what if you’ve collected your own pistachios from the backyard orchard? If you plan on storing them in the fridge or freezer, the same rule applies as above. But if you want to keep them at room temperature, you’ll have to freeze them first.

Pistachios can be infected by insects and harmful bacteria. Did you know that the number one pathogen found on pistachio is Salmonella? This will make you think twice before eating pistachios straight from the orchard. 

By freezing them first for two days, you’re making sure that any living organisms found in pistachios are long gone.

Final Thoughts

Like most nuts, pistachios stay fresh for quite some time. 

When kept at room temperature, their shelf life is about six months. If that doesn’t seem like enough time, you can store them in the fridge or freezer instead. In that case, they’ll retain freshness for up to three years.

Just remember that pistachios are sensitive to air, heat, and moisture. In order to prevent premature degradation, they should be stored in airtight packaging. 

Related articles:

How useful was this post?

Click on a heart to rate it!

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

Photo of author

Author

I’m not a pro chef by any means, but years of tinkering inside the kitchen have taught me a thing or two about preparing delicious, healthy food. So whether you’re interested in how to properly store food, figuring out side dishes for your main course, or even learning how to use a knife properly – I've got you covered.