Does Oat Milk Go Bad? How Long Does Oat Milk Last Refrigerated & Unrefrigerated

Does Oat Milk Go Bad?

Oat milk is a natural choice for people who are allergic to lactose, nuts, and soy. Additionally, you can also find gluten-free oat milk, making it cater to all kinds of lifestyles. But like regular milk, oat milk comes with an expiration date.

Generally, oat milk lasts for a week after opening the packet. But you can elongate its shelf life by storing it correctly. Wondering how? Well, we have the answers to your questions in the following article.

Continue reading to explore more about shelf-life, storage methods, spoilage signs, and the risk of drinking spoiled oat milk.


How Long Can Oat Milk Last?

Let’s learn how long your oat milk can last in different circumstances.

How Long Does Unopened Oat Milk Last?

The unopened Oat Milk is shelf-stable and has a long shelf life. It lasts for at least a few months more than its use-by date printed on the label, provided that it is stored properly.

How Long Does Oat Milk Last In The Pantry?

The shelf-stable Oat Milk comes with a use-by date, and it is usually between nine months to 12 months from the date of production. The refrigerated variety of Oat Milk has a shorter shelf-life of a couple of weeks.

How Long Does Oat Milk Last After Opening?

So, the shelf-stable Oat Milk lasts way longer than refrigerated Oat Milk. After opening, you must finish the Oat Milk within seven days, as per Toast Oats Company.

Items Pantry Fridge
Oat Milk Shelf-Stable Use-By Date Plus Three to Six Months
Oat Milk Chilled Carton Use-By Date Plus Five to Seven Days
Opened Oat Milk Five to Ten Days

Please note that these are the estimates to tell how long it keeps its peak quality and not the expiry date.


Signs of Oat Milk Spoilage | How can you tell if Oat Milk has gone bad?

What are the Spoilage Signs of Oat Milk, Does Oat Milk Spoil

Oat Milk never goes rancid all at once. It starts showing spoilage signs gradually and eventually becomes sour and gross to drink. So, here is the list of spoilage signs that you have to check before using the old oat milk.


Oat milk emits an unpleasant smell when it goes rancid. So, you have to check the smell before using it. And if it radiates any unpleasant smell, discard it.

Taste Change

If you are in doubt, taste the Oat Milk. The Oat Milk will give a sour taste when it goes bad. The milk breaks down and gives a sour taste, indicating that the milk has gone bad.

Mold Formation

If there are any blue or green spots on the milk, airborne spores have started growing in the milk. It occurs when you leave the container open outside the fridge or if there is any defect in Oat Milk’s carton.

Color Change

Oat Milk has a light brown and creamy color, but the color changes to yellow as it gets off. So, if you see solid yellow spots in the milk, discard them.


If the milk gets thicker or there are lumps in the milk, it indicates that it is no longer safe for consumption. When your Oat Milk gets bad, it thickens to the point where it starts to congeal, making the texture lumpy.


What are the Risks of Eating Oat Milk After Expiry?

What Happens When You Eat Bad Oat Milk

Unfortunately, if you lack meeting the storage requirements of Oat Milk, it will go rancid quickly past its use-by date. Gradually, the milk will start changing its color, texture, taste, and smell.

Can Bad Oat Milk Give You Food Poisoning?

Drinking spoiled Oat Milk can make you sick. Even the unopened carton of Oat Milk can make you sick if it is not stored properly or the carton is damaged. The opened Oat Milk is exposed to environmental elements and air, and it comes in contact with bacteria and pathogens.

These may make the milk harmful and inedible. So, consuming contaminated Oat Milk can make you sick with symptoms of upset stomach, vomiting, gas, bloating, and even diarrhea. So, it is important to check the spoilage signs before using them.

If you notice a strange smell and moldy residues, discard the milk, as it can cause serious health issues, like fever, fatigue, and stomach cramps, with other signs of food poisoning.


Does oat milk need to be refrigerated?

Can You Freeze Oat Milk Refrigerated, Does oat milk need to be refrigerated?

Both refrigerated and shelf-stable varieties last six months when stored in a freezer. But, freezing may cause texture change. Besides, the cold temperature may also cause the ingredients to settle and get grainy at the bottom.

So, it is necessary to freeze the Oat Milk at a consistent temperature, and the best place is to store it at the back of the freezer, away from other food items. You must use an airtight container to freeze the Oat Milk and leave sufficient space in the container to give room for expansion as the liquid may expand when frozen.


If you have not broken the carton seal, it is safe to refrigerate it, and it tends to last for seven days past its use-by date. After opening, it must be refrigerated continuously because it is prone to airborne contaminants. You must be wondering whether oat milk goes bad if left out after opening. The Answer is Yes. If you leave it outside a fridge, it tends to spoil in less than four days.

How to Store Homemade Oat Milk?

Homemade oat milk lacks the preservatives found in store-bought oat milk. So, the homemade variety tends to have a shorter shelf-life of four to five days, provided that it is stored in a fridge.



Some Oat Milk varieties are sterilized when packaged, increasing their shelf-life and making them shelf-stable. It means you can store them in your pantry until it is sealed and unopened. The shelf-stable Oat Milk lasts between one and three months after its best-before date.

The carton must be stored in places away from heat and light sources. The back of the pantry and or cupboard works fine for its storage. After opening, it is best to store the Oat Milk in a fridge and ensure not to leave the opened carton outside the fridge for more than two hours to prevent airborne contamination, as per USDA.


What Is The Best Way To Store Oat Milk?

What are the Best Methods to Store Oat Milk

No matter which variety of Oat Milk you have purchased, the storage requirements for all types are the same. Apart from meeting the storage requirements for your Oat Milk, there are a few other basic storage practices that you must know to extend the shelf-life of your Oat Milk.

Store in Cool and Dry Places

The shelf-stable variety of Oat Milk must be stored in dark, cool, and dry places. The location you choose to store the Oat Milk must be away from extreme temperatures and direct sunlight.

After opening the carton, you must transfer it to the refrigerator to offer a good storage environment for your Oat Milk.

Keep Carton Sealed Tightly

After opening the carton of Oat Milk, you must ensure to keep the carton sealed tightly after every use. Keeping the carton loose or open increases the chance of contamination, and exposure to air can make the milk go bad quickly.

It is always best to transfer the milk into an airtight container for storage. It helps the milk to stay safe and prevents airborne contamination. A glass jar or plastic container is always the best choice to store the leftover Oat Milk to sustain its freshness.

What Can You Do With Expired Oat Milk?

If you do not want to risk your health by consuming expired oat milk, you can use them in the following manner:

  • Apply it to the skin to soothe irritated skin.
  • Combat frizziness and unmanageable hair.
  • Make it into a lip balm.

What are the Alternatives to Oat Milk if it has gone bad? 

If your oat milk has started showing signs of spoilage, you can replace it with the following alternatives:

  • Hemp milk
  • Almond milk
  • Coconut milk
  • Soy milk
  • Cow’s milk

Frequently Asked Questions


Do Ingredients of Oat Milk Separate After Freezing?

The basic Oat Milk ingredients don’t separate when frozen, but they may separate when placed in acidic and hot drinks. The ingredients settle at the bottom, so you can fix it by shaking the container. Some brands have added substances like rapeseed oil, which separates after freezing.

How to Know Whether Oat Milk is Shelf-Stable or Not?

Normally, you will see the shelf-stable variety of Oat Milk on the grocery store’s shelf and the refrigerated variety in the frozen or dairy foods department. You may also check the label of the Oat Milk to know if it is a shelf-stable variety or non-shelf stable. The shelf-stable variety only keeps its quality until sealed, and after opening, it requires refrigeration.

How long does oat creamer last?

It is best to consume oat creamer within 5-7 days after the packet is opened. It is advisable to store it in the refrigerator if you plan on using it within the following 12-14 days.

Does Oat Milk Really Go Bad 7 Days After Opening?

Oat milk retains its quality for 7-10 days after opening its packet. While the dates might vary as per the brand, it is best to consume it within the time frame or store it properly to elongate its shelf life.

The Bottom Line

By now, you are aware that Oat Milk can go bad as it won’t last indefinitely. All the dates and periods mentioned above are estimations. Oat Milk probably won’t last as long as expected, or maybe it will keep its quality even longer than estimated.

If you are unsure about the Oat Milk’s quality, it is wiser to err on the side of caution and check for spoilage signs before using it. Consuming bad or spoiled Oat Milk is risky as it causes negative effects on your wellbeing.

So, stay cautious and check spoilage signs before using old Oat Milk sitting in your fridge for a couple of days already.

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