Does Nutritional Yeast Go Bad?

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Nutritional yeast is a pantry staple for many vegans. Like other dry goods that tend to sit on the back shelf, it can be forgotten about from time to time.

So, does nutritional yeast go bad? The short answer is yes, nutritional yeast does expire and it certainly can go bad. But the timeline around this depends on many factors.

Keep reading to find out how long nutritional yeast keeps, how to tell when it’s gone bad, and to learn a few tricks to extend nooch’s shelf life.

How Long Does Nutritional Yeast Keep?

In general, a new batch of nutritional yeast will keep for about two years with minimal risk of going bad. Nooch that was purchased in an air-tight container or jar is likely to last a little longer than bulk nutritional yeast flakes and powder that have been transferred from one container to another.

This is because bulk yeast is more likely to have been exposed to oxygen more often. And oxygen is one of four things that hastens the degradation process of nutritional yeast and other dry product foods. In addition to oxygen, exposure to moisture, heat, and light will also increase how quickly your nooch goes bad.

How Long Is Yeast Good After The Expiration Date?

Like the expiration dates printed on many dry goods, the expiration date on bottles of nutritional yeast is really just an estimate of the minimal amount of time the product will last.

If the nutritional yeast was kept away from light, heat, moisture, and oxygen, odds are, it will last a lot longer than the date printed on the packaging. How long, exactly, again will depend on the source of the nooch and how you have stored it. 

Instead of going off an exact timeline, your best bet is to use your senses to determine if the nooch is still good before you use it. More on how to tell if nutritional yeast has gone bad in a minute.

Can Unopened Nutritional Yeast Go Bad?

Packaged nutritional yeast is sealed against invading oxygen and moisture. This type of product is much less likely to spoil quickly than nooch from the bulk bin.

Even if the package is never opened, prepackaged nooch can eventually go bad.

Most of the degradation it’ll experience will come from exposure to light and heat, which will cause nutrient damage but shouldn’t make the product dangerous to consume. 

But even a sealed package can let minute amounts of oxygen in overtime. With this oxygen, comes tiny amounts of moisture that can speed up the spoiling process.

Once again, two years is a good place to start as a cut-off for how long you should keep unopened nutritional yeast before throwing it out.

How Long Is Nutritional Yeast Good After Opening?

Once you open a prepackaged container of nooch, you immediately introduce oxygen and moisture into the environment. How much oxygen and moisture is introduced over the course of using the nooch will determine how long nutritional yeast flakes and powder will last after opening.

If stored in a dry, dark location in an air-tight container, most nooch will stay good for two years after being packaged. Assuming your storage methods are adequate, this remains true even if the container has been opened.

Can I Use Expired Nutritional Yeast?

Dry goods don’t immediately go from perfectly fine to rotten overnight. So, it makes sense that you have a little leeway when it comes to expiration dates. 

What the expiration date of your favorite cheese substitute is really telling you is when your product is likely to stop tasting as fresh as it should. 

If you notice changes in taste, smell, and, most importantly, consistency, it’s time to toss out your nooch and replenish your supply with a fresh batch. This is true whether the expiration date has come to pass or not.

Is Nutritional Yeast Supposed To Be Refrigerated?

Nooch does not need to be refrigerated. It’s a shelf-stable product that should be stored in a dark, dry place. That said, storing your nooch in the fridge can help prolong its life.

The fridge offers two things that are beneficial for extending the shelf life of nooch. One, fridges are pitch-black most of the time, which means limited exposure to degrading light. And two, refrigerators are nice and cool.

The nutrients and enzymes in nooch are more likely to stay good for longer in a cool environment. 

How to Tell If Nutritional Yeast Has Gone Bad

There are two ways nooch can go “bad.”

The first way is by getting stale. Stale nooch won’t hurt you, but it doesn’t taste as good as it should. Nooch generally goes stale when it is very old or when it has been exposed to free-flowing oxygen for an extended period.

Stale nooch has a lighter color than the deep golden color or yellow color of fresh nutritional yeast. It will also lose its nutty, cheesy aroma and give off little to no odor. The cheesy and nutty flavor will also be greatly reduced and that typical stale taste will take over.

Nooch will also go bad if exposed to moisture. This can quickly lead to mold growth that can cause the product to spoil. 

If you notice your nooch has suddenly gotten darker or browner in color, has a malty or sour smell, or if it has become clumpy, throw it out. Nooch that has a noticeably bitter taste or malty flavor should also be thrown out. These are all signs your nooch has gone bad.

Can You Get Sick From Expired Nutritional Yeast?

Stale or expired nutritional yeast on its own will not make you sick. The nutrient content is much lower in older nutritional yeast, but it won’t harm you. As we discussed before, these shelf life dates are only estimates of when your product might start to turn.

When old nooch becomes dangerous to eat is when it’s been exposed to moisture and mold. Just as moldy bread and flour can make you sick, so can moldy nutritional yeast.

Nooch that is clumpy or has spots of green, brown, or blue, is definitely not safe to eat and should be thrown out.

If you find yourself suddenly out of nooch and in need of a substitute, check out these nutritional yeast substitutes that work surprisingly well.

Does Nutritional Yeast Contain Mold?

Fresh nooch should not contain any mold. 

The product consists of active yeast cells raised on a medium of beet molasses or sugarcane. Much of the nutritional content comes from nutrients added to that medium or mixed with the yeast after it’s been harvested. Once it’s done growing, the active yeast, or yeast microbes, are heated and turned into inactive yeast product.

Unless something has gone terribly wrong during this process, the final product should contain only deactivated yeast. 

If the product is exposed to moisture at any point after the drying process, mold can be introduced and grow on the yeast product. This is most likely to happen in humid environments and if dry spoons are not used to remove nooch from the container. Any water contact will introduce moisture and possibly mold to the product.

Expert Tip: How to Store Nutritional Yeast So It Lasts

If you want to keep your nutritional yeast from going bad, you need to store it correctly. 

In most cases, this means keeping your nutritional yeast in a cool, dry, dark place. The back of the pantry or in a cupboard typically works well. 

You do not want to store your nutritional yeast on the counter or on a shelf that gets a lot of light.

In addition to keeping your nooch in the right spot, you also want to keep it in the right container. 

Store it in the original bag until you open it. If the original container seals tightly and doesn’t let too much light in, you can keep it in that bag until you use it up.

If the bag is not resealable, transfer the unused nutritional yeast to a sealable mylar bag. This will help keep the product stable so it lasts longer.

How to Use Nutritional Yeast

Nutritional yeast makes a great addition to many dishes thanks to its savory flavor and umami tasting notes. 

Here are a few of our favorite recipes that feature nutritional yeast:

If you love these recipes and our vegan cooking tips, be sure to sign up for our newsletter to get more like vegan goodness delivered right to your inbox.

Store Nutritional Yeast for Lasting Enjoyment

Nutritional yeast does go bad, eventually. Most new products should last around 2 years if stored properly. That means keeping it in a cool, dark, dry location, such as in the back of the pantry.

What is your favorite way to use up your nutritional yeast so it doesn’t go bad? Let us know by posting in the comments below!

Sara Seitz

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