The guidelines in this post were retrieved from the CDC’s post on Proper Storage and Preparation of Breast Milk. There are variations of the recommended guidelines for milk storage. Practice your own judgment and always check if the breast milk has gone bad prior to feeding.
There are many reasons why one would pump and store breast milk. You may be pumping to increase your milk supply, or maybe you have an oversupply. You may be planning to return to work soon, or need to pass on the feeding responsibilities to another caretaker.
This is when safely stored expressed breast milk comes in handy!
So what do you need to know about storing breast milk?
Making sure that your breast milk is safe for your baby and for your pumped breast milk to not go to waste can be a tricky process to navigate.
This post will walk you through the breast milk storage guidelines, breast milk storage tips, how to thaw frozen breast milk, and all the burning questions you might have about breast milk storage!
Breast Milk Storage Guidelines
- First things first, wash your hands and storage containers thoroughly before expressing breast milk by hand or with a pump.
- If you plan on feeding your baby with this pumped milk within the next 4 hours, you can leave it out at room temperature! If your breast milk won’t be used in the next 4 hours, consider storing your milk in the refrigerator or freezer.
*It is safe for your breast milk to be left at room temperature at or below 25C or 77F for up to 4 hours after expression, however, it may be best to place it in the fridge immediately to prevent the rapid growth of pathogens if possible. - When storing your breast milk, use dedicated breast milk storage bags, clean glass, or hard BPA-free plastic bottles with tight lids. Check the bottom of your containers to make sure that it does not have the “recycle number 7” logo on them, this indicates it may contain BPA.
- If your baby didn’t finish the bottle, any breast milk that is left after feeding should be used within 2 hours. If it’s been over 2 hours, throw away the milk in that bottle.
- Do not refreeze breast milk after it has been thawed completely. If there are still ice crystals present, you may put the breast milk back in the freezer.
A good way to prevent wastage is to store breast milk in the refrigerator or freezer in 2-4 ounce batches or in single servings (the serving amount your baby usually consumes in one feeding).
This table shows the safe storage guidelines according to different temperatures for a quick reference:
| Location | Safe Storage Duration |
|---|---|
| Room Temperature (77F / 25C or colder) | 4 hours |
| Refrigerator (39F / 4C) | 4 days |
| Freezer (0F / -18C) | 6-12 months |
How to Thaw Frozen Breast Milk
First of all, never microwave your breast milk. It can break down the precious nutrients in your breast milk and create hot spots which can burn your baby’s mouth.
If your breast milk is frozen, put some breast milk in the refrigerator the night before. Alternatively, you can thaw right before a feed by placing the breast milk in a container of warm or lukewarm water, or directly running the container under lukewarm water.
And how long is thawed breast milk good for? Be sure to use up all your thawed breast milk within 24 hours, starting from when it was completely thawed. Once your breast milk is brought to room temperature, use it up within 2 hours.
Baby bottle warmers are a great alternative for thawing and heating your expressed breast milk too. However, not all baby bottle warmers are created equal.
Make sure it does not warm the milk above 104F (40C), which can destroy the beneficial properties of your breast milk. It should effectively heat milk to 98.6F (37C), which is also the average normal body temperature and likely the temperature your baby is accustomed to from your breasts.
Be sure to test the milk temperature on your wrist before feeding it to your baby to ensure it is a safe temperature!
High Lipase Breast Milk
Have you ever noticed a weird taste or scent with your pumped breast milk?
Some individuals may produce breast milk with higher lipase activity, which can cause the fats to break down more than normal after expression, leading to a soapy, metallic, or fishy aroma that babies may reject.
The rate of breakdown varies from one person to another – some may notice an unpleasant odor or flavor in less than 12 hours, while some remain completely normal for up to a few days. However, even if this odd aroma is detected, there is nothing wrong with high lipase breast milk, it is still safe and nutritious!
Freezing your milk does not slow down the lipase activity that is causing this to happen. If you already have a bunch of pumped milk and your baby is rejecting it all, a great workaround is to mix half of your previously pumped milk with freshly expressed milk. The freshly pumped breast milk will hopefully reduce the unpleasant flavor.
If your baby still rejects the milk, try scalding your milk before freezing to de-activate lipase activity:
- Gather all of the milk that you expressed throughout the day to scald them all in one batch
- Heat your breast milk on low in a clean pan, just until small bubbles form around the edges (not boiling)*
- Cool the pan of breast milk in ice water to accelerate the cooling process
- Store in your desired containers for storage
*Do not let it boil or else you risk losing all the precious immunological properties!
Storage Tips
- Label your breast milk storage bags with the date it was expressed. It is important that you are keeping track of how long your breast milk has been in storage!
- Leave about 1-inch of space at the top of your breast milk storage container or bag. Breast milk will expand when frozen, and you do not want them exploding off the top!
- Never store breast milk in disposable bottles or sandwich bags that are not meant for breast milk.
- If you are traveling, you can store your breast milk for 24 hours in an insulated cooler with frozen ice packs. Once you get to your destination, store your breast milk in a refrigerator or freezer. Read: Breastfeeding and Traveling with a Baby
- Place your breast milk in the coldest part of your fridge or freezer – this is typically at the back. Avoid storing them in the door compartment as this can lead to temperature abuse from the door opening and closing.
- Even though the freezer can keep food safe for a very long time, follow storage times to prevent nutrient decline! Studies have shown the longer the breast milk is stored or frozen, the more the decline in fat and caloric content.
Frequently Asked Questions (FAQ)
Practicing safe breast milk storage is crucial for the safety of your baby. The best way to store your precious breast milk is to immediately place it in the fridge after expression. This can help you avoid forgetting it and leaving it out at room temperature for too long.
If you have extra breast milk that needs to be stored for longer, place them in the freezer and label them accordingly!
For those with high lipase milk, although it is perfectly safe for consumption, scalding the breast milk can help reduce any flavors and aromas that may be causing your baby to reject the pumped milk!
More blog posts here:
- What to Do with Leftover Breast Milk
- Introducing Breastfed Baby’s First Bottle And How To Bottle Feed With Paced Bottle Feeding
- Breastfeeding and Traveling with a Baby
The guidelines in this post were retrieved from the CDC’s post on Proper Storage and Preparation of Breast Milk. There are variations of the recommended guidelines for milk storage. Practice your own judgment and always check if the breast milk has gone bad prior to feeding.
Pingback: Introducing Breastfed Baby's First Bottle and How To Bottle Feed With Paced Bottle Feeding - Milk & Grow