Do Pistachios Go Bad?

Seeing pistachios on a sale is not something that happens often, so when it does, you want to pounce on the opportunity. But before you do, you need to know how long pistachios last, and how to pick the best ones.

In this article, we talk about storage, shelf life, and going bag of pistachio nuts. If you’re looking for a primer on that, you’re in the right place. Let’s dive in.

Bunch of pistachios
Bunch of pistachios

How To Store Pistachios

Before we cover how to store those nuts at home, let’s first talk about buying them.

You want them fresh and crunchy, not old, stale, and dried. To get the best ones, consider the following:

  • if you’re buying from the bulk bins in the supermarket, make sure there’s high turnover; otherwise, you have no idea how long they sit there for
  • if you’re unsure of the freshness (ask the seller if possible) of pistachios sold in bulk, go for packaged ones (and check the label for dates)
  • sample one or two nuts if possible

If you’re not sure that the pistachios you buy are any good, stick to a smaller amount. And if you want them to last in good quality for an extended period, go with the unshelled ones.

Pistachios in a mesh bag top down
Pistachios in a mesh bag top down

Okay, now that you got home with the nuts, and you’re done snacking, it’s time to put them away. How to go about that, you ask?

For starters, go with advice from Santa Barbara Pistachio Company [SBP]:

We recommend that you store pistachios in an airtight container in a cool dark place.

The container can be either glass or plastic. Or if you’ve bought the pistachios packaged, use the one they come in instead. In most cases, it would be a resealable one, so there’s no need to switch containers even after opening the package.

Lack of access to fresh air and light helps with preventing the nuts from going rancid ([WIKI]).

The place is the last piece of the storage puzzle.

Pile of pistachios
Pile of pistachios

Should Pistachios be Refrigerated?

The best answer I can give you here is: it depends. Let me explain.

All tree nuts (like e.g., almonds) generally keep better at lower temperatures. Pistachios are no different. Low temperature means the rancidification process goes slower, keeping your pistachios fresh for longer.

Plus, some manufacturers and websites clearly state that you should keep pistachios in the fridge.

But there’s an equal number of people and places that say room temperature is just fine, especially for the short term. And I don’t know about your supermarket, but the bulk bins with pistachios in mine aren’t in the refrigerated section. Same for packaged pistachio nuts.

The bottom line here is that refrigeration or freezing is best for long-term storage, but a dark cabinet in the pantry or kitchen is good enough for a few months.

If you’re refrigerating pistachios, make sure you seal them tightly. Otherwise, they might pick up some smells from the fridge. You don’t want that.

Pistachios in a black scoop
Pistachios in a black scoop

How Long Do Pistachios Last?

If you scoured the Internet looking for answers to this question, you would find that they are all over the place. Some say pistachios last only a week in the pantry, and up to six months if frozen. Others state that the periods are much longer. In short, there’s no consensus here.

What I go with is somewhere between what the Food Keeper app ([FK]) says and what the mentioned Santa Barbara Pistachio Company ([SBP]) states on their website.

The former says pistachios last up to 3 weeks in the pantry, a year in the fridge, and up to 2 years frozen. The latter informs that pistachios stored in a cool dark place:

Kept in this way, pistachios will retain their distinctive crunch for up to 6 months.

For me, the estimated shelf life of shelled pistachios in the pantry is around five months (plus one month for unshelled), 12 months in the fridge, and 24 months in the freezer.

Please note that’s just my estimate, and that everyone has a different opinion on this.

If you buy packaged pistachios, they come with a date on the label. Don’t be super strict about it. If it’s only a couple of months past it, check the nuts using the instructions from the next section to learn if you can eat those or not.


PantryFridgeFreezer
Shelled pistachios5 months1 year2 years
Unshelled pistachios6 months1 year1 year
Pistachios in a mesh bag closeup
Pistachios in a mesh bag closeup

How to Tell If Pistachios Are Bad?

Some of the typical signs of pistachios that have gone bad are:

  • shriveled, dried out nutmeat
  • mold on the surface
  • bugs in the package

If either one is present, toss the nuts out.

But if you take good care of them, the worst that could happen is that they go rancid from prolonged storage. How do you know if pistachios are rancid?

Unfortunately, you usually can’t see if the pistachios are rancid or not. But you can smell and sample them to find out. If the nut smells like paint, or its taste is harsh and bitter, you know that the fats in the nut are spoiled.

An important thing to note here is that eating rancid nuts won’t make you sick ([UOC]), but consuming lots of these definitely isn’t healthy. Fortunately, the unpleasant taste should force you to discard those. If it doesn’t, get rid of them either way.

Last but not least, your pistachios might seem to be okay, but taste a bit stale and lose their crunch. If that’s the case, shell them and toast at 200 degrees F (~90 C)  for 10 to 15 minutes ([SBP]) to get some of that crispness back. Give them a few minutes before wolfing them down.

Pistachios Storage and Shelf Life FAQ

Can you eat pistachios past their expiration date?

As I’ve already mentioned, you don’t need to be super strict about the date on the label. It’s just an estimate. If the nuts aren’t a year past their date, I’d still open the package and checked the quality of its contents.

If the nuts are dried out, or the first two or three ones taste bitter, toss all out. Now that you know that they are spoiled, you can get rid of them without feeling guilty.

Can You Eat Closed Pistachios?

Pistachios open their mouths when they mature, so a closed one usually means it’s immature. Plus, opening one isn’t as easy as opening an open-mouth one.

If you like, feel free to open them up (using a knife or a nutcracker), but most times, you won’t find much inside.

Sources