Understanding the Shelf Life of Oat Milk: Does It Go Bad?

How long does oat milk keep? Does it go bad?

Oat milk has gained popularity as a delicious, dairy-free alternative to traditional cow’s milk. Whether you’re lactose intolerant, have a dairy allergy, or simply prefer plant-based milk options, oat milk offers a creamy texture and slightly sweet flavor that make it a favorite among many consumers. However, like any perishable product, oat milk has a limited shelf life and can spoil if not stored properly. In this article, we will explore the factors that affect the shelf life of oat milk, how to store it properly, and how to determine if it has gone bad.

What is oat milk?

Oat milk is a non-dairy milk alternative made from oats. It is made by soaking oats in water, then blending and straining the mixture to extract the liquid. The resulting liquid is oat milk, while the remaining oat pulp is discarded. Oat milk has a taste similar to cow’s milk, with a slight hint of oats. It is slightly sweeter than dairy milk, making it a popular choice for adding to hot beverages.
Oat milk has several nutritional benefits. It is rich in vitamins and minerals, including manganese, phosphorus, folate, zinc, selenium, iron, and copper. Compared to cow’s milk, oat milk is lower in sugar and higher in fiber. It is also suitable for people who are allergic or intolerant to dairy or nuts. However, it’s important to note that some oat milk products may be processed in facilities that also handle gluten-containing grains, so individuals with gluten sensitivities should check the packaging carefully.

Shelf Stable vs. Refrigerated Oat Milk

Oat milk comes in two main forms: shelf-stable and refrigerated. Shelf-stable oat milk is processed to eliminate unwanted microorganisms and can be stored at room temperature until the carton is opened. Refrigerated oat milk, on the other hand, is considered a fresher product and must be stored in the refrigerator both before and after opening.
If you purchase shelf-stable oat milk, it can be stored in a cool, dry place such as a pantry or kitchen cupboard. It’s important to keep it away from direct sunlight and extreme temperatures. Shelf-stable oat milk typically has a long shelf life, often up to 9 months from the date of production. However, it’s always a good idea to check the “use by” or “best by” date printed on the carton and consume it before that date for the best quality.
Refrigerated oat milk, as the name suggests, must be kept in the refrigerator at all times. This type of oat milk has not been processed to eliminate microorganisms, so refrigeration is necessary to prevent bacterial growth and maintain freshness. It’s worth noting that the refrigerator door is subject to greater temperature fluctuations than the shelves, so it’s best to store oat milk on one of the refrigerator shelves rather than the door.

How long does oat milk keep?

The shelf life of oat milk depends on whether it has been opened or not. Unopened, shelf-stable oat milk can be kept for several months past the sell-by date if stored properly. However, it’s important to carefully inspect the product for any signs of spoilage before consumption.
Once a carton of oat milk is opened, it will begin to spoil. The exact length of freshness can vary depending on the brand and storage conditions, but in general, refrigerated oat milk should be consumed within 4-7 days of opening. It’s important to follow the manufacturer’s recommendations on the label regarding when to consume.

Signs of spoilage

To determine if oat milk has gone bad, it’s important to know the signs of spoilage. Here are some indicators that oat milk may no longer be safe to consume:


If the oat milk has become lumpy, watery, or slimy in texture, it is likely spoiled and should be discarded.


While the smell of oat milk may not change significantly until it is well past its prime, a sour or off odor is a clear indication that it has gone bad.

Color & Appearance:

Fresh oat milk is typically creamy white in color. If you notice an unusual color or the presence of mold on the surface or inside the container, it’s best to avoid consumption.


If the taste of the oat milk is noticeably different from when it was first opened, or if it tastes off, it is a sign that it has begun to spoil. It’s best to throw it away.

Proper Storage Practices

To maximize the shelf life and quality of oat milk, it’s important to store it properly and follow these guidelines:

  1. Store unopened, shelf-stable oat milk in a cool, dry place away from direct sunlight and extreme temperatures. Be sure to keep the package closed until you’re ready to use it.
  2. After opening shelf-stable oat milk or if you purchase refrigerated oat milk, always store it in the refrigerator. Choose a shelf rather than the refrigerator door for more consistent temperature control.
  3. Use clean utensils or pour oat milk into a separate container when serving to avoid introducing contaminants that can accelerate spoilage.
  4. Tightly reseal the carton or properly seal the container after each use to prevent air exposure and maintain freshness.
  5. Avoid cross-contamination by keeping oat milk away from raw meat, poultry, and seafood in the refrigerator.
  6. If you have leftover oat milk that you don’t plan to consume within the recommended time frame, consider freezing it in an airtight container. Freezing can extend its shelf life, but be aware that the texture may change slightly after thawing.

Remember, these guidelines are general recommendations, and it’s important to check the specific instructions provided by the oat milk manufacturer. If you have any concerns about the quality or safety of oat milk, it’s best to err on the side of caution and throw it away.

The Bottom Line

Oat milk is a popular dairy-free alternative that offers a creamy texture, slightly sweet taste, and nutritional benefits. However, like any perishable product, oat milk can go bad if not stored properly. The shelf life of oat milk depends on whether it is unopened or opened, and whether it is shelf-stable or refrigerated.
Shelf-stable oat milk can be stored in a cool, dry place for months until opened, while refrigerated oat milk must always be stored in the refrigerator. Once opened, oat milk should be consumed within 4-7 days when refrigerated. It’s important to know the signs of spoilage, such as changes in texture, odor, color, or taste.
By following proper storage practices and the recommended consumption timeline, you can enjoy fresh oat milk and avoid potential health risks associated with consuming tainted products.


How long does unopened, shelf-stable oat milk last?

Unopened, shelf-stable oat milk will keep for several months past the expiration date if stored properly in a cool, dry place.

How long will refrigerated opened oat milk keep?

Once opened, refrigerated oat milk should be consumed within 4-7 days to ensure freshness and prevent spoilage.

What are the signs that oat milk has gone bad?

Signs of spoilage in oat milk include changes in texture (lumpy or slimy), sour or off odor, unusual coloration or presence of mold, and a noticeably different taste.

Can I freeze oat milk to extend its shelf life?

Yes, you can freeze Oat Milk in an airtight container to extend its shelf life. However, be aware that the texture may change slightly after thawing.

Can I store oat milk at room temperature?

Shelf-stable oat milk can be stored at room temperature until opened, but once opened, it should be refrigerated to maintain freshness and prevent spoilage.

Can I consume oat milk after the expiration date?

It’s generally recommended that oat milk be consumed before the sell-by date for the best quality. However, if the oat milk shows no signs of spoilage, it may still be safe to consume, but use caution and judgment.