Does Nutritional Yeast Need to be Refrigerated?

September 8, 2024

28 15 minutes read

Does Nutritional Yeast Need To Be Refrigerated

What is Nutritional Yeast?

Before we get into the specifics of storage, let’s clarify what nutritional yeast actually is. Nutritional yeast (nicknamed “nooch”) is an inactive form of the yeast species Saccharomyces cerevisiae, the same type used to make bread and beer.^[2] However, unlike active baker’s or brewer’s yeast, nutritional yeast has been deactivated through heating and drying so it can no longer leaven baked goods or ferment sugar into alcohol.

The yeast is grown on a purified medium, often molasses, then harvested, washed, pasteurized and dried into flakes or a powder. The resulting product has a savory, almost cheesy flavor and is packed with nutrients like B-vitamins, trace minerals, and even contains all nine essential amino acids, making it a complete protein.^[3] Many brands also fortify their nutritional yeast with additional B12.

Because of its taste and nutrition, nooch has long been a favorite of vegans and vegetarians looking to add umami flavor to foods without dairy cheese. It’s delicious on popcorn, pasta, salads, soups, and more. But even non-vegans have embraced nutritional yeast for its unique flavor and health benefits in recent years.

Does Nutritional Yeast Need to Be Refrigerated?

So now to the main question at hand: does nutritional yeast need to be refrigerated? The good news is, not necessarily. Nutritional yeast is shelf-stable and does not require refrigeration to be safe to eat.^[4] You can store it in a cool, dark pantry or cupboard in an airtight container and it will be just fine.

However, many brands and nutritional yeast aficionados do recommend storing it in the fridge, especially after opening the package. Refrigerating nooch can help preserve its B-vitamin content and potency.^[5] The cooler temperature may also prevent the natural fats in the yeast from going rancid as quickly, helping it stay fresh for longer.

What is the Shelf Life of Nutritional Yeast?

Unopened nutritional yeast stored in a cool, dry place can last up to two years before any noticeable degradation in flavor or quality.^[6] However, once opened, its shelf life is more limited. Manufacturers generally recommend using nutritional yeast within 3-6 months of opening the package when stored at room temperature, or within one year if refrigerated.^[7]

Keep in mind these are just general guidelines though. The actual shelf life can vary depending on the specific brand, how it was processed and packaged, and the storage conditions in your home. Nutritional yeast won’t necessarily spoil or become unsafe to eat past these dates, but it can start to lose its flavor potency and vitamin oomph.

How to Store Nutritional Yeast?

Whether you choose to refrigerate or not, always keep nutritional yeast in a tightly sealed container to maintain freshness. Nooch can easily absorb moisture from the air, which can make it clumpy and prone to spoilage. Keeping it in an airtight jar, resealable bag, or the original packaging if it seals tightly will prevent humidity and pantry pests from getting in.^[8]

It’s also best to store nutritional yeast away from heat sources and direct light, both of which can degrade its nutrients more rapidly. A dark pantry shelf or opaque container can help shield it from light damage. Some people also opt to keep nooch in the freezer for even longer storage up to two years, where it will stay fresh but won’t clump from humidity like it can in the fridge.^[9]

Why is Refrigeration Recommended for Nutritional Yeast?

While not required for safety, storing nutritional yeast in the fridge has some benefits for maintaining its quality and shelf life. The cool temperature can protect its nutrients and prevent spoilage. Here’s a closer look at the potential advantages:

Preserving B-Vitamins

One of the top reasons to refrigerate nutritional yeast is to preserve its B-vitamins, especially if it’s a fortified brand. Nooch is particularly prized as a vegan source of vitamin B12, which is normally only found in animal products. However, B-vitamins are sensitive to heat and light and can degrade over time in storage.^[10]

A 2018 study published in the journal Food Science and Biotechnology found that light exposure significantly decreased the vitamin B12 content in nutritional yeast, with losses of 85-93% over 6 months when stored under light versus in the dark.^[11] Lower temperatures can slow down this degradation process, helping the yeast retain more of its initial vitamin content.

So if you rely on nutritional yeast as a key source of B12 or other B-vitamins in your diet, refrigerating it in an opaque container can help you get the most nutritional bang for your buck. The fridge is especially wise if you tend to take a while to get through a package.

Preventing Spoilage

Another benefit of refrigerating nutritional yeast is extending its shelf life by preventing spoilage. Like other dry goods, nooch contains some natural oils that can go rancid over time, especially in warm or humid conditions. Rancidity not only smells and tastes bad, but can degrade the nutritional value too.

Keeping nutritional yeast in the fridge slows down the oxidation process that leads to rancid fats, so your nooch will taste fresh for longer. The cool temperature also deters pantry pests like insects that could potentially invade the package in the cupboard. No one wants to find bugs in their yeast!

Maintaining Optimal Flavor

Since nutritional yeast is mainly used as a flavorful seasoning, you want it to taste its best. Refrigerating can help nooch maintain that optimal savory, umami flavor for longer compared to room temperature storage. This is because the aromatic compounds that give nutritional yeast its cheesy taste can gradually volatilize and fade over time, especially with exposure to heat and air.

By keeping it cold and tightly sealed, your nutritional yeast will be at peak deliciousness every time you sprinkle it on popcorn or stir it into sauce, even if the package has been open for a few months. The fridge is your friend for locking in that yummy flavor!

What Happens If Nutritional Yeast is Not Refrigerated?

If you choose to store nutritional yeast at room temperature in the pantry instead of the fridge, it’s not the end of the world. Unrefrigerated nooch is still perfectly safe to eat as long as it’s kept dry and tightly sealed. It just may not stay at optimal quality for quite as long.

The warmer temperature can cause the B-vitamins and flavors to degrade faster, so your nutritional yeast may lose some of its potency and cheesy taste more quickly compared to refrigerated yeast. You’ll want to use it up within the shorter 3-6 month timeframe after opening rather than stretching it to a year or more like you could in the fridge.

Pantry storage may also make nutritional yeast more prone to absorbing moisture and humidity from the air, which can lead to clumping and spoilage. It’s extra important to use a very tightly sealing container and check for any signs of mold or off-smells if storing nooch at room temp, especially in hot or humid weather.

As long as your nutritional yeast still looks, smells, and tastes good, a stint in the pantry won’t ruin it. You may just notice the flavor and nutrition is slightly less potent after a few months than the fresh stuff in the fridge. If you go through nooch quickly, the difference may not be very noticeable!

What are the Potential Health Risks of Not Refrigerating Nutritional Yeast?

In general, unrefrigerated nutritional yeast does not pose any major health risks as long as it is stored properly. Nooch is a shelf-stable product that does not require refrigeration for safety, though the cooler temp can help it stay fresh and nutritious for longer.

The main potential issue with room temperature storage is that nutritional yeast may lose some of its vitamin content more rapidly, especially if exposed to light or air. But it would still be safe to eat, just not quite as healthy. The only time unrefrigerated nooch might be risky is if it has spoiled from moisture or contamination.

Can Nutritional Yeast Go Bad?

Like any other food, nutritional yeast can indeed go bad under certain conditions, especially once the package has been opened. The main enemies of nooch freshness are moisture, heat, light, and air exposure. If nutritional yeast absorbs humidity from the environment, it can start to mold or ferment.

Nooch that has gone bad may become clumpy, discolored, or develop an off-smell like stale beer or rotten eggs instead of the normal cheesy aroma.^[12] If you see any signs of mold, dark spots, or odd smells in your nutritional yeast, err on the side of caution and throw it out rather than risk eating it. Spoiled yeast won’t be effective and could potentially make you sick.

Proper storage is key to preventing nutritional yeast from going bad prematurely. Always keep it in a tightly sealed container away from moisture and heat. Using clean, dry utensils to scoop from the package rather than your hands can also minimize contamination that could lead to mold growth.

Can You Get Sick from Eating Spoiled Nutritional Yeast?

It’s unlikely that eating a small amount of “expired” nutritional yeast would cause any serious illness, but it could lead to some unpleasant digestive symptoms. Spoiled yeast may cause nausea, vomiting, or diarrhea if consumed in large quantities.^[13]

The bigger issue is that moldy yeast could potentially be contaminated with mycotoxins, which are toxic compounds produced by certain fungi. Mycotoxins like aflatoxin can cause liver damage, cancer, and other health problems in high doses.^[14] However, the risk of mycotoxin exposure from spoiled nutritional yeast is likely very low in reality.

To be on the safe side, always inspect nutritional yeast for any signs of spoilage before consuming it, especially if it’s older or was stored in less than optimal conditions. When in doubt, throw it out! It’s not worth risking potential food poisoning or toxin exposure to save a few bucks.

How to Tell If Nutritional Yeast Has Gone Bad?

The best way to tell if your nutritional yeast has spoiled is to give it a good look and sniff before using it. Fresh nutritional yeast should be a consistent light yellow color with a powdery or flaky texture. It will have a strong cheesy, nutty smell but should not be overly pungent.

What are the Signs of Spoiled Nutritional Yeast?

Some red flags that nutritional yeast has gone bad include:^[15]

Mold: If you see any fuzzy growth, green or white spots, or other signs of mold on the surface, the yeast is no longer safe to eat. Mold can spread invisibly throughout the package even if you only spot it in one area.
Discoloration: Darkening or browning of the yeast can be a sign that it has started to oxidize and go rancid. While a slight darkening may just indicate reduced flavor, significant color change is a sign it’s past its prime.
Clumping: Some clumping is normal for nutritional yeast, but excessive clumping or hardening can mean it has absorbed moisture and may be starting to mold or spoil. Nooch should be mostly powdery and easy to break apart.
Off smells: Instead of the usual savory, cheesy aroma, spoiled yeast can start to develop a stale, musty, or sour smell. If it smells “off” in any way, it’s best to discard it.
Strange taste: If the flavor is weak, bitter, or just doesn’t taste right, the yeast may be past its prime even if there are no visible signs of spoilage. Nooch should taste nutty, cheesy and delicious, not “dead.”

When in doubt, always err on the side of caution and throw out any nutritional yeast that looks or smells questionable. It’s not worth risking your health to save a bit of money on old yeast! Nooch is relatively inexpensive, so don’t feel bad about replacing it if needed.

How to Properly Store Nutritional Yeast?

Now that you know how nutritional yeast can go bad, let’s talk about how to store it properly for optimal freshness, flavor, and nutrition. With the right storage techniques, you can keep your nooch in top form for many delicious meals to come.

Should Nutritional Yeast Be Stored in the Fridge or Pantry?

The ideal storage spot for nutritional yeast depends on how quickly you go through a package and your household environment. Here are some general guidelines:

Pantry: If you use nutritional yeast frequently and expect to finish an opened package within 3-6 months, storing it in a cool, dry pantry or cupboard is sufficient. Just make sure it’s in an airtight container away from heat and light.
Fridge: If you take longer than 6 months to use up nutritional yeast or live in a hot, humid climate, refrigerating it can help extend the shelf life and preserve the B-vitamins. The fridge is also a good choice for bulk packages that will last a while.
Freezer: For even longer storage up to 2 years, you can keep nutritional yeast in the freezer. It will stay fresh and potent without risk of clumping from humidity like in the fridge. Portion it into airtight bags or containers so you can easily grab what you need.

Whichever storage method you choose, the key is to keep nutritional yeast away from moisture, air, heat, and light. These elements can all speed up spoilage and nutrient loss. Always use clean, dry utensils to scoop from the package to avoid contamination.

Can You Freeze Nutritional Yeast?

Yes, nutritional yeast can be frozen for long-term storage! In fact, the freezer is one of the best places to store nooch if you want it to stay fresh and flavorful for a year or more. The cold temperature locks in the nutrients and flavor while preventing clumping from humidity.

To freeze nutritional yeast, scoop it into airtight containers or resealable bags, pressing out as much air as possible. Label and date the packages so you know how old they are. When ready to use, let the yeast come to room temperature before opening the container to prevent moisture condensation.

One convenient trick is to pre-portion nutritional yeast into small bags with just enough for a recipe or a few uses. That way you can easily grab what you need from the freezer without having to thaw a whole package at once. Use frozen nooch within 2 years for the best flavor and potency.

What is the Best Way to Store Nutritional Yeast for Long-term Use?

If you want to stock up on nutritional yeast and store it for the long haul, your best bet is to keep it in the fridge or freezer. The cool temperature will preserve the B-vitamins, flavor, and freshness for a year or more, so you can buy in bulk without worries.

When storing nutritional yeast long-term, it’s worth investing in high-quality airtight containers like glass jars or thick plastic tubs with tight-fitting lids. This will protect the yeast from moisture, air, and pantry pests that could sneak in and cause spoilage.

It’s also a good idea to portion the yeast into smaller containers or bags before refrigerating or freezing, rather than storing a huge tub that will be opened and closed many times. Exposing the yeast to air and temperature changes every time you open the package can degrade the quality more quickly.

Label and date your storage containers so you can keep track of how old the yeast is and use the oldest stuff first. As long as it’s kept airtight and cool, nutritional yeast can stay tasty and nutritious for well over a year! Just check for any signs of spoilage before using older yeast to be safe.

FAQs

Does nutritional yeast go bad if not refrigerated?

Nutritional yeast is shelf-stable and does not require refrigeration for safety. However, storing it at room temperature can cause the flavor and nutrients to degrade more quickly compared to refrigerated yeast. Unrefrigerated nooch may lose potency and go rancid within 3-6 months after opening, while refrigerated yeast can last up to a year. Proper storage in an airtight container is key to preventing spoilage at any temperature.

How do you store nutritional yeast after opening?

After opening a package of nutritional yeast, store it in an airtight container in a cool, dry place away from light and heat. Glass jars, plastic tubs, or resealable bags work well. Squeeze out excess air before sealing to prevent moisture and oxidation. You can store the container in the pantry, refrigerator, or freezer depending on your climate and how quickly you use the yeast. Always use clean, dry utensils to scoop from the package to avoid contamination.

When should you not eat nutritional yeast?

You should not eat nutritional yeast if it shows any signs of spoilage, such as mold, discoloration, clumping, off-smells, or strange tastes. Spoiled yeast may cause digestive upset and could potentially be contaminated with harmful mycotoxins. If the yeast has been stored for a long time or in poor conditions, inspect it carefully before consuming. When in doubt, throw it out! It’s not worth risking your health for old yeast.

Can nutritional yeast be left out of a recipe?

In most cases, you can leave nutritional yeast out of a recipe if you don’t have it or don’t like the flavor. It is typically used as a cheesy, savory seasoning and is not crucial to the structure or texture of dishes. However, omitting nutritional yeast from recipes that rely on it for flavor, like vegan cheese sauces or tofu scrambles, may result in a blander final product. You can try substituting other savory ingredients like miso paste, soy sauce, or vegetable broth to boost the umami taste.

Should yeast nutrient be refrigerated?

Yeast nutrient, a supplement used in homebrewing and winemaking, does not require refrigeration. Like nutritional yeast, it is shelf-stable and can be stored in a cool, dry place in an airtight container. However, refrigerating or freezing yeast nutrient may help extend its shelf life and potency over the long term, especially after opening. Always check the manufacturer’s storage instructions and best by date on your specific product.

Does nutritional yeast get destroyed by heat?

Nutritional yeast is heat-stable and does not get destroyed by normal cooking temperatures. In fact, it is often used as a seasoning in cooked dishes like pasta, casseroles, and sauces. The savory flavor and nutrients hold up well to heat.

However, excessive heat above 300°F (150°C) for prolonged periods may start to degrade some of the B-vitamins and amino acids in nutritional yeast.^[16] Very high temperatures can also cause the yeast to brown and develop off-flavors. So while moderate cooking is fine, avoid scorching your nooch!

Takeaways

Nutritional yeast is a shelf-stable product that does not require refrigeration for safety, but storing it in the fridge or freezer can help extend its shelf life and preserve nutrients.
The cool temperature of the fridge protects B-vitamins, prevents spoilage, and maintains optimal cheesy flavor in nooch for up to a year after opening.
Unrefrigerated nutritional yeast stored in a cool, dry pantry is still safe to eat but may lose potency more quickly, within 3-6 months after opening.
Always store nutritional yeast in a tightly sealed container away from moisture, heat, and light to prevent early spoilage and nutrient loss.
Signs that nutritional yeast has gone bad include mold, clumping, discoloration, off-smells, and strange tastes. Discard any yeast that appears spoiled.
For long-term storage up to 2 years, keep nutritional yeast in the freezer in airtight containers or portion into small bags for easy use.
With proper storage, nutritional yeast can stay fresh and delicious for many tasty meals to come! Just be sure to label containers with the date and use the oldest yeast first.

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