5: The New Breastmilk Storage Guidelines

Hey mama, today I’m going to share to current guidelines for breast-milk handling and storage. We’ll talk about how to keep things clean, how long breastmilk is good at room temperature, and freezer rules.

First off, you gotta keep things hygienic. Which I know sounds straight forward, but you’d be surprised how often this simple step gets skipped. So please wash your hands when you are handling breastmilk, bottles, and pump parts. I mean legitimately thoroughly wash them not the pretend version that is sometimes necessary when your hands are super chapped and raw from wintertime or fear of COVID.

Next, make sure you are properly cleaning your bottle and/or pump parts. Most manufacturers recommend initial sterilization (either with boiling water or a sanitization kit)- I hear mixed recommendations on how necessary this is if you are using safe clean water, but I don’t think initial sterilization is a bad idea since you wouldn’t let your baby lick the factory they’re made in anyway.

After the initial cleaning, most directions say you can wash with warm soapy water and the right size brush for full term healthy babies (but of course always check the directions). The second half to proper washing is proper drying- this is so so important since things grow in small damp places. Things you don’t want your baby to eat. So make sure you have a clean surface that is well aired for all the little parts to fully dry. Now when it comes to pump parts, you only want to wash the parts the milk touches, many pumps have tubing that is not supposed to get wet with water or milk and if they do you would want to get them replaced, because again, things grow in small damp places.

Now- you may be wondering, What can I put this breastmilk in? (Or you may not be wondering that in which case you can just tune this part out). Breastmilk can be stored in any clean food grade container with a good seal. There are tons of things on the market made specifically to contain breastmilk, each with their own pros and cons, but they should be BPA free plastic or led free glass etc.. You can even use clean glass Tupperware with a tight fitting lid. Again there are tons of food grade safe options. If you choose glass and plan to freeze the milk- just double check they are freezer safe and avoid taking super cold glad and warming it too quickly because as this can break the glass.

Another container tip is to use the least amount of containers possible, since each time your transfer the milk or pour it to a new container it is potentially exposed to germs and you lose a little milk on the side of each container. For example, if your baby will be drinking the milk you’re pumping within the next few days- consider just pumping or expressing directly into the bottle they use if the cuff fits appropriately with your pump. This saves dishes and minimized milk transfers.

Okay now that you have clean hands, surfaces, and clean parts without things growing in them, and you’ve express the milk- here are the current breastmilk storage guidelines.  These are for a standard temperature range in the U.S. of:

77 degrees Fahrenheit or cooler being the average room or Countertop temperature (that’s 25 degrees c);

40 degrees Fahrenheit for the refrigerator (that’s 4 degrees C)

Or 0 degrees F or colder for the freezer (that’s -18 degrees C)

(If you know you live in a particularly tropical area, say you live in Florida and your AC breaks in the middle of August, please adjust accordingly because it’s unlikely your house will stay under 77 degrees Fahrenheit as the countertop temperature.)

Freshly pumped or expressed milk is perfectly fine at room temperature for up to 4 hours. That means if you are pumping before an errands and dad is feeding the baby in a couple of hours you can just leave it on the countertop.

If you need it for longer than four hours, then pop it in the fridge for up to 4 days, or a cooler with icepacks until it gets to the fridge. The colder part of the fridge the better. Don’t worry if it separates and looks like there’s cream on the top- this is normal and it literally is the milk fat separating. Warming and mixing it up will incorporate it back in to the rest of the bottle.

If you know you won’t use it within four days, then go ahead and put it directly into the coldest part of your freezer. Some resources recommend up to three months, but others say up to 6 months is fine. I’ve even seen that if it stays frozen the whole time then 12 months in the freezer is fine. Most resources suggest if you are going to keep frozen milk for longer periods it’s best to freeze it as fresh as possible and use a deep freezer if available.  If you plan to stock frozen milk for longer periods, keep in mind that breastmilk is a living food made to order- so 12 month old freezer milk given to your 13 month old toddler was made for them when they were 1 month old. I don’t think it’s bad for them, just something to know.

(One time we lost power with a hurricane, when I had a freezer stash of milk for my son Henry- and l was so relieved when it came back on any everything was still frozen and not in that partially thawed sweaty state. The irony for me was that he never really accepted freezer milk anyway. He was more of a fresh from the tap or fridge kind of baby.)

Here are some more helpful freezer tips:

It’s okay to layer milk from different pump sessions to save in the same container.

Leave at least one inch of space at the top of the container since it will expand as it freezes. Label each pack with the date, you’ll want to know when choosing which to thaw and you’ll need the dates if for any reason you choose to donate your extra milk to a baby in need.

Okay, once you thaw out frozen milk- it’s good for 1-2 hours at room temperature or 1 day in the refrigerator (and you get the whole 24 hours on this so 3 pm thawed in the fridge today is good until 3 pm in the fridge tomorrow for example, and the clock doesn’t start until the milk is thawed. Once it’s thawed- you never refreeze it; you use it or lose it.

When you thaw breastmilk you can: A. put it in the fridge the night before (this is my favorite and frankly I think the easiest) or B. use lukewarm water (notice I said lukewarm not hot). You either place it in a bowl or large cup of lukewarm water, or hold it under running water avoiding the part where the top is sealed on (so it sort of just bobs around with the cap sticking out ),or you hold it with the top just out of the water.

Never ever-ever put breastmilk in a microwave. Not only does it destroy nutrients but it can literally burn your baby’s mouth. Even if you test the temp and it feels fine, microwaves can create hot spots so you won’t know until that hot milk in inside your crying baby’s mouth. (Someone out there has a parent or in-law that is going to attempt to use the microwave and when you tell them not to, they’ll have a story about how they did it all the time for their babies were fine and yadda yadda….but no please no microwaves.)

I’m often asked about unfinished bottles. If the milk leftover is still any good. Well, I am a huge proponent of following your baby’s satiation cues and not having them finish the bottle just because there is milk leftover. So firstly, store, freeze, and prepare milk in appropriate amounts- don’t offer your young baby 5-6 ounces of milk when that is way too large for their stomach and they typically show signs they are done after say 2-3 ounces. That will reduce waster significantly. After a feed, then milk the bottle does have saliva in it- but it’s still good for 2 hours after that feed. So if it was a smaller feed, or there is a measurable amount of liquid gold left- -you can hang on to it in case they cue for a feed or a sip over the next couple of hours. But for quality feeding sake- don’t try to force it or override their cues.

If this seemed like a lengthy explanation for breastmilk storage then let me give you a simple recap. Remember to keep things clean, store in appropriate food grade containers, and follow the 4-4-6 rule. Four hours on the counter, four days in the fridge, or 6 months in the freezer. I hope this clears up any questions you may have about the current guidelines for breastmilk handling and storage and saves you some googling time. I’ve also including a link below if you want to see the source.

Resources for Breastmilk Handling Guidelines: https://www.cdc.gov/breastfeeding/recommendations/handling_breastmilk.htm

Cadwell, K., & Turner‐Maffei, C. (2013). Pocket Guide for lactation Management (3rd ed.). Jones and Bartlett Learning.