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Can Pistachios Go Bad? (What About Unshelled Pistachios)

Quick Answer

The unfortunate truth is that yes, pistachios can go bad. When stored in particularly humid or warm conditions for a long period of time, pistachios will go bad, which is also known as turning “rancid”. You’ll soon know whether your pistachios are rancid or not due to the sharp and bitter taste they’ll have, instead of their usually delicious nutty flavor.

Another way you’ll be able to tell whether or not your pistachios have gone rancid is down to the smell. A lot of people report that rancid pistachios have a similar smell to that of paint or even crayons. However, not all rancid pistachios give off these smells, but it’s worth smelling them first just to check.

If you happen to eat a rancid pistachio, don’t worry too much, as they’re not unsafe. But you really won’t like the experience of eating a rancid pistachio, so you should throw them out as soon as possible. But, your pistachios turning rancid isn’t the only sign that your pistachios have spoiled, so let’s have a look at some of the other ways to tell if your pistachios have gone bad.

If you’re a fan of delicious nuts, then there’s a good chance that you’re a fan of pistachios, which also probably means that somewhere in a cupboard in your pantry there’s a bag of pistachio nuts just waiting to be eaten.

However, what happens when you go to eat the pistachios and you realize that the pistachios have exceeded the expiration date found on the packaging?

It’s then you’ll begin to wonder, can pistachios go bad?

Can Pistachios Go Bad

This is why we’ve created this guide to provide you with all of the information you need to know about the storage and shelf life of pistachios.

Knowing whether your pistachios are still good to eat or not is important information, so if you’re unsure, it’s best that you read onwards!

Signs That Your Pistachios Have Gone Bad

There are a whole host of causes for your pistachios being spoiled, and if you notice any of them, you should throw them away immediately:

Pantry Bugs

If your bags of pistachios reside in your pantry, then even the smallest of insect issues can lead to your pistachios being spoiled.

So unless you keep your pistachios in a sealed container or zipped bag, then chances are that the insects will find their way to your favorite nutty snack.

If you notice any dead insects, eggs, or any sign of insects in your nuts, then get rid of them as soon as possible.


Forgetting you have items sitting in your pantry is a common thing, but if you notice an unlikely growth of mold on your pistachios, then you should definitely throw them away, no matter how hungry you are!

Rancid Pistachios

The most common way for your pistachios to go bad, you should always check the taste and smell of your pistachios before you serve them up.

If you notice a bad smell or a bitter taste, then you should definitely toss them.

The first two problems are incredibly unlikely, and the most likely cause of your pistachios turning bad is simply because they’ve turned rancid.

But, it is worth noting that pistachios don’t turn rancid that easily.

In fact, because of the low amount of unsaturated fats within pistachios, it’s unlikely they’ll go rancid at all.

So, what happens if you go to eat some pistachios, and although they aren’t rancid, they just don’t taste as good as they did before?

Stale Pistachios

Leaving a bag of pistachios open can often lead to them going stale. No worries, however, as we have all the tips and tricks to help revive their taste:

Toast Them

Toast Pistachios Go Bad

By toasting your pistachios on a skillet or in the oven, it should help to return at least a little bit of the taste.

They still won’t be as good as new though.


If your pistachios have gone a little bit stale, you can always add them into a dessert to help mask some of that staleness!


Why not use your stale pistachios in a baking project?

Whether you search for a specific recipe that calls for the use of pistachios, or you just add them to your usual cupcakes or muffins!

What About Unshelled Pistachios?

Now, you may be wondering “what if I have a packet of unshelled pistachios?”

Well, not all of your unshelled pistachios are going to open up over time, and finding that your unshelled pistachios randomly have small cracks in them is completely natural.

These pistachios should still be fine to eat, so simply unshell them as you normally would and enjoy!

CanPistachios Go Bad

Storing Your Pistachios

So, if you’re looking for the best way to store your pistachios, here’s what we recommend:

In The Refrigerator

You can absolutely store your pistachios in the fridge!

Just place them into a sealed airtight bag or container, and you should have no problem with eating them whenever you’d like!

Room Temperature

No room in your fridge? No problem!

You can store them at room temperature simply by placing them in an airtight container and keeping them in a dark and cool place.


Surprisingly, yes! You can freeze your pistachios.

Place them into a freezer bag, making sure to squeeze out all of the air, then seal them and place in the freezer!

Defrosting them is easy too, just place the number of pistachios you want on the countertop and let them sit for 30 minutes before eating!


To summarise, yes, your pistachios can go bad.

Whether they turn rancid, or simply lose some of that amazingly fresh and nutty taste, finding out that your pistachios have gone bad can be really disheartening.

Whilst you should obviously throw away your pistachios if they have turned rancid, there are some great ways that you can still make use of your stale pistachios to ensure that they don’t go to waste.

Additionally, there is also a whole load of ways of storing your pistachios to ensure that you can enjoy them whenever you’d like, without worrying about whether they’re stale or rancid.

So, we hope you’ve found this guide useful, and that you can now eat and store your pistachios with full confidence, enjoy!

Jess Smith