Breast Milk Storage Guidelines

baby with bottled breast milk

If you are planning to pump breast milk you will want to know how long it can be stored at room temperature, in the refrigerator, or in the freezer. Breast milk can be stored in special freezer bags designed for breast milk or any hard plastic or glass container. If you have extra baby food jars, these are the perfect size to store breast milk in.

What Are the Basic Breast Milk Storage Guidelines?

Breast milk may be left at room temperature for up to 10 hours if the temperature is between 66-72°F (19-22°C). If you’ve left pumped breast milk out in room temperature conditions within the last 4-8 hours, it is best to use it at your next feeding or discard the supply.

When storing breast milk in the refrigerator at around 32-39°F (0-4°C), it is best to use the supply within 3-8 days or transfer it to the freezer to prolong its lifespan.

Storing breast milk in a freezer compartment will last up to two weeks. However, storing it in a freezer at around 4°F (20°C) will last significantly longer, around 3-4 months. Deep freezers can prolong the lifespan to 6-12 months. Once frozen breast milk is thawed, it should be used within 24 hours. Do not refreeze.

Can You Add Pumped Breast Milk to Already Frozen Breast Milk?

breast milk stored in tupperware

Yes, but it is best to cool in the refrigerator and use right away.

If you add pumped milk to already frozen milk, it can cause the frozen breast milk to thaw and refreeze. The other problem with adding fresh breast milk to frozen breast milk is that you will have to use it by the date on the already frozen milk. It makes it harder to keep track of how old your breast milk is.

How Can You Tell if Breast Milk is Spoiled?

If you are properly storing your milk, you should not have a problem with spoiled milk. Breast milk will separate. The fat will rise to the top. This is normal and does not mean your milk is spoiled.

You may sometimes have thinner looking or blue-colored milk, and this is still okay. Another concern comes along when moms or caregivers smell breast milk. Sometimes breastmilk that is frozen or stored in the refrigerator will smell soapy or have a strange taste to it. This does not mean it is spoiled. Before you toss out perfectly good breast milk, consider how it was stored. If it was refrigerated after pumping and stored properly, it probably doesn't need to be tossed. However, if you are concerned or if the milk smells rancid or sour, go ahead and toss it.

What Size Portions Should You Store Breast Milk In?

It is better if you store breast milk in small portions (around 3-4 oz per freezer bag or storage container). Once frozen milk is thawed, you can not refreeze it. If you store breast milk in 8-10 oz portions, you may end up wasting breast milk if your baby does not drink it within 24 hours.