How to Store Your Breastmilk Safely
One of the toughest parts of breastfeeding is knowing how to store all that milk you pumped! Get it wrong, and you could either make your baby sick or you could lose a lot of those important nutrients your baby needs!
Along the way, I’ve learned a lot of do’s and don’ts when storing your breastmilk so it is the best and safest for your baby!
Here is how you store your milk:
***This post may contain affiliate links to products I use and love. Before implementing any health advice, please check with your doctor first as I am not a medical professional. Read my full policy for more information.
Freshly Expressed Milk
So, you just pumped your milk, now what? First, decide on how you plan to use this milk. If you are planning to use it within 4 hours, you can leave it at room temperature until needed (source). If you are not planning to use it right away, you will need to put the milk in a storage bag or sterilized bottle and place it in the fridge.
When I was talking to my lactation consultant, she reminded me that you need to chill the milk before you freeze it. So, make sure you always put your milk in the fridge first and wait until it has been chilled (can take a couple of hours depending on how much milk you have!) before putting it in the freezer.
According to the CDC, breastmilk stored in the fridge is good for up to 4 days. After 4 days, you can either freeze it or use it (source)!!
If you are planning to mix your freshly pumped breastmilk with milk that is already in the fridge, you will need to chill the milk first. Otherwise, you will lose some great nutrients in your milk if you mix warm milk with chilled milk. Always best to chill milk before mixing.
So, how do you label your mixed milk? You will need to write the earliest date on the storage bag. So, if you are adding milk you pumped on, say, February 4th with milk pumped on February 6th, you’ll label the storage bag as February 4th.
If you are pumping at work and you use an insulated cooler bag with an ice pack, the milk is good for 24 hours.
Storage Guidelines
Here is a breakdown of how your breastmilk should be stored according to the CDC:
| Storage Location and Temperatures |
| Type of Breast Milk | Countertop 77°F (25°C) or colder (room temperature) | Refrigerator 40°F (4°C) | Freezer 0°F (-18°C) or colder |
| Freshly Expressed or Pumped | Up to 4 Hours | Up to 4 Days | Within 6 months is best Up to 12 months is acceptable |
| Thawed, Previously Frozen | 1–2 Hours | Up to 1 Day (24 hours) | NEVER refreeze human milk after it has been thawed |
| Leftover from a Feeding (baby did not finish the bottle) | Use within 2 hours after the baby is finished |
It’s well worth investing in a deep freezer if you don’t already have one! If you don’t have much space in your current freezer, you’re probably not going to have a whole lot of room for your breastmilk.
What to Remember When Storing Your Breastmilk:
- Ensure your pump parts are clean and sterilized before use (your dishwasher will automatically sterilize your pump parts and storage containers). Make sure they are dry before use. When they are dry, store them in a ziplock bag to ensure they stay clean.
- Always wash your hands before handling your breastmilk to avoid any contamination.
- Label your storage bags with the date you pumped your breastmilk so you know when it is safe to use. If you are giving your milk to a daycare provider, ensure you write your baby’s name on the bag.
- Only use storage bags that are specifically designed to hold breastmilk.
- Do not store your breastmilk in the fridge or freezer door as the temperature is constantly changing.
How Much Milk Do I Store in Each Bag?
The first time I stored milk, it was a disaster! I stored it in batches of 6-8 oz and I ended up losing a lot of milk! Once your breastmilk is thawed, it is only good for 1-2 hours. My baby would drink 4 oz and the rest was thrown out.
The next time I stored milk, I stored it in batches of 4 oz. Well, when my baby was ready for baby cereal, he only needed 2 oz of milk mixed with the baby cereal. He was then uninterested in drinking the other 2 oz so it was a waste!
The third time, I got it right! Wahoo!! Some bags had 2 oz (perfect for baby cereal) and some had 4 oz of breastmilk (for bottle feeding when I’m gone!). If my baby was still hungry after 4 oz, I would get a 2 oz bag and it filled him up! Perfect!
Make sure you store your milk in good-quality bags. I use these breastmilk storage bags as they are the thickest bags I’ve used. When I used thin bags, shards of iced breastmilk would pierce the bag. When I thawed the milk, it leaked everywhere and was no good!
How to Safely Thaw Your Breastmilk
There are 2 easy ways to thaw your milk:
- Put the breastmilk in the fridge to thaw out. Once it is thawed, it is good for 24 hours in the fridge (source).
2. Put the breastmilk bag in a clean sink and run hot water over it. This is my favorite method as it takes me a minute or 2 to thaw. It also warms the milk up so there’s no need for a fancy bottle warmer! Win-win!!
Please make sure your sink is clean before using this method to prevent contamination. The best way to clean your sink, that’s safe for your baby, is the good old-fashioned soap and water.
My Thawed Milk Smells Like Metal or Soap, Has it Gone Bad?
Not necessarily (although it could be a sign of incorrect storage, so be careful!). If you have stored your breastmilk correctly, then the milk is safe for your baby.
So, my milk always smelled like metal after it’s been frozen for a month or so. The first time, I threw it all away as I thought it was not safe anymore. Turns out, it’s ok! I just wasted all that perfectly good milk! Whoops!
So why did my milk smell like metal? Turns out, my breastmilk is high in lipase. This is what gives it that metal or soapy smell. This is perfectly safe for your baby.
My first baby hated the taste but my other two were completely fine with it. There is a way to prevent this from happening to your milk and it is pretty easy to do.
Put your milk in a pan over low heat. Once the milk is bubbling at the sides (not boiling as this will damage the milk), remove the pan from the heat and store it in the fridge until chilled. Then, you can freeze the milk and it won’t taste or smell different!
So there you have it! The basics of storing your breastmilk! Hope you found this helpful! You’re doing great mama!!
