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What can I do with old oat milk?

Oat milk has become an increasingly popular plant-based milk alternative in recent years. However, like other dairy-free milks, oat milk has a relatively short shelf life once opened. So what should you do if you have a carton of oat milk that’s reached its expiration date or is starting to smell or taste sour? Thankfully, there are many uses for oat milk past its prime so you don’t have to waste it.

Check the Expiration Date

First, check the expiration or “use by” date on your oat milk carton. Unopened, oat milk can typically last 5-10 days past its printed expiration date if refrigerated. Once opened, it will stay fresh for about 7-10 days in the fridge. If your unopened oat milk is within a week or two of expiring, you’re better off using it rather than letting it go bad.

Look and Smell for Freshness

In addition to the date, you can use your senses to determine if your opened oat milk is still good. Look at the consistency – if it’s become chunky or watery rather than creamy, it’s time to toss it. Give it a sniff – sour or “off” odors mean it’s no longer fresh enough to drink. If the taste is any hint of sour or bitter, it’s gone bad.

Use in Baking and Cooking

One of the easiest ways to use up oat milk is by substituting it for regular milk or other liquids in baking recipes. The slight oat flavor pairs especially well with baked goods like muffins, breads, pancakes, and oatmeal cookies. You can typically swap oat milk in a 1:1 ratio for the dairy milk or water called for in the recipe. The extra fiber and nutrients oat milk provides can even make baked goods healthier.

Oat milk also works well in many savory cooking applications. Use it when making oatmeal, cream soups, mashed potatoes, or cream sauces. The neutral flavor won’t overwhelm savory dishes. You can even use it to make overnight oats by combining with oats, chia seeds, fruit, and spices and chilling overnight.


Blend expired oat milk into smoothies and protein shakes. The sweet flavor pairs nicely with fruits and veggies. The consistency is also perfect for creating a creamy, drinkable texture. Some tasty smoothie combinations are:

  • Berry – Oat milk, mixed berries, banana, spinach, flaxseed
  • Tropical – Oat milk, mango, pineapple, coconut flakes
  • Green – Oat milk, kale, avocado, mango, lime
  • Protein – Oat milk, peanut butter, banana, chocolate protein powder

Overnight Oats

As mentioned above, oat milk’s inherent creaminess makes it an ideal base for overnight oats. This is one of the easiest ways to use up older oat milk. Simply mix together:

  • 1/2 cup oats
  • 1/2 cup oat milk
  • 1 tbsp chia seeds
  • Pinch of cinnamon
  • Fruit, nuts or other toppings of choice

Refrigerate overnight so the oats soak up the oat milk and become soft and creamy. Top with your favorite fruits, nuts, seeds or other add-ins in the morning.

Oat Milk Iced Lattes

Make iced lattes at home using expired oat milk. Combine strong chilled coffee or espresso with oat milk and your choice of sweetener over ice. Top with flavors like cocoa powder, cinnamon, vanilla or caramel. You can even blend the drink for a frothy, latte-like texture.

Use for Cereal

One of the most obvious uses is pouring your older oat milk over cereal. The light sweetness complements both sweeter and more savory types of cereal. Make sure your cereal of choice doesn’t contain so much sugar that it clashes with the extra sweetness from sour oat milk.

Granola and Oatmeal

Another way to use up less-than-fresh oat milk is by pouring it over granola, regular oatmeal or overnight oats. The texture and flavor marries perfectly with the hearty grains. Use it in place of regular milk or yogurt. Top your oats or granola with fresh fruit too.

Chia Pudding

Chia pudding is easy to whip up using oat milk. Simply combine in a jar:

  • 1 cup oat milk
  • 1/4 cup chia seeds
  • 1 tsp vanilla extract
  • Pinch of cinnamon
  • 2 tbsp sweetener like honey, maple syrup or sugar

Stir, cover and refrigerate at least 2 hours until thickened. Top with fruit, coconut, nuts or granola.


Here is an example data table visualizing quarterback stats:

Player Team Passing Yards Passing TDs Interceptions Rushing Yards
Patrick Mahomes Chiefs 5,097 41 13 340
Tom Brady Buccaneers 4,643 25 9 73
Josh Allen Bills 4,407 36 15 763
Aaron Rodgers Packers 3,695 26 7 115

This table allows readers to easily compare passing and rushing stats between top NFL quarterbacks. Visualizing the data in a table makes it simpler to draw insights than just looking at raw numbers.

Use in Savory Cooking

In addition to baking, oat milk that’s gone slightly sour can be used in place of regular milk or cream in savory cooking and dishes. The subtle sweetness and mild flavor won’t overwhelm most recipes. Some ideas for using up less-than-fresh oat milk include:

  • Soups – Substitute oat milk 1:1 for regular dairy milk or cream in soups. It works for both cream and broth-based soups.
  • Mashed potatoes – For fluffier, creamier texture without heavy cream, use oat milk instead.
  • Chowders – The richness works well in clam chowder, corn chowder and other creamy chowders.
  • Hot cereals – Cook oatmeal, cream of wheat or grits in oat milk instead of water for extra richness.
  • Gravies and sauces – Add instead of regular milk to cream sauces, pan sauces and gravies.
  • Creamy pasta – Use when making pasta dishes like fettuccine alfredo, mac and cheese or pasta primavera.

The neutral flavor won’t overwhelm most dishes. You can typically swap out regular dairy milk for oat milk at a 1:1 ratio.

Use for Your Pets

If your furry friends will drink it, oat milk that’s expired or slightly sour can make an excellent treat for cats and dogs. The nutrients are safe for pets, though the lactose may cause digestive upset in some animals. Introduce slowly and monitor your pet’s reaction.

Both cats and dogs often love the sweet, creamy taste and texture of oat milk. Try pouring a small amount in their water dish or over their food. You can also pour it into ice cube trays or popsicle molds with pet-safe fruits and make healthy treats.

Fruit Smoothie Bowls

Another way to use up extra oat milk is by making thick, creamy fruit smoothie bowls. Blend together:

  • 1 cup oat milk
  • 1 frozen banana
  • 1 cup frozen berries or other fruit like mango, pineapple, etc
  • 2-3 tbsp yogurt or protein powder (optional)
  • 1 tsp honey, maple syrup or other sweetener

Blend until thick and creamy, then pour into a bowl. Top with fresh fruit, granola, coconut, chia seeds or toasted nuts.

High-Protein Smoothies

Outdated oat milk has enough substance to make thick, satisfying protein shakes too. Blend it with:

  • Scoop of protein powder
  • 1 frozen banana
  • 1 cup spinach or kale
  • 1 tbsp nut butter
  • 1 tbsp chia or hemp seeds
  • Ice cubes

The oat milk provides creaminess while the add-ins pack a big punch of protein. Adjust the ingredients to your own taste.

Oat Milk Iced Coffee

Iced coffee is delicious when made with oat milk instead of regular dairy milk or creamers. In a blender, combine:

  • 1 cup strong brewed coffee, chilled
  • 1/2 cup oat milk
  • 1 tbsp maple syrup or other sweetener
  • Pinch of cinnamon
  • Ice cubes

Blend until frothy. Pour into a glass over ice and enjoy!


Don’t be so quick to toss out that carton of oat milk in your fridge just because it’s passed its prime. With a little creativity, you can put expired or souring oat milk to use in many different ways. From baking and breakfasts to smoothies and coffee drinks, oat milk adds nutrients, richness and sweetness past its expiration date.

Always give it a smell, taste and look test rather than going just by the date. If it seems off, then it’s best not to consume it. But in many cases, you can safely cook and bake with oat milk even if it’s no longer palatable on its own. So check your senses, get creative in the kitchen and make the most of the plant-based goodness in that forgotten carton of oat milk.