Once you return to work and have figured out how to pump at work and when to pump at work, you will need to decide how to store breast milk after pumping. This will vary greatly from mom to mom depending on a mom’s breast milk supply and how much breast milk is needed for your baby’s bottles. Moms that have an oversupply, or who pump more milk than their baby needs for the next day’s bottles, will need to devise a system for saving the extra breast milk they pump. Moms who have an under supply or those who produce just enough breast milk for their baby’s bottles will not need to be as concerned with how to store breast milk after pumping.
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When you get home from work, fill your baby’s bottles for the next day as soon as you can. That way you can wash your pump parts and leave them to air dry overnight, or you can place them into the dishwasher. If you have more breast milk than you need for your baby’s bottles, you have a few options on how to store breast milk after pumping:
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1. Immediately store breast milk after pumping in a storage bag and freeze
We recommend freezing breast milk in increments that match the volume of one of your baby’s bottles. This way you can easily grab a frozen bag that matches your baby’s bottles when necessary. For example, if your baby takes four 3-oz bottles while you are at work, then freeze your breast milk in 3 ounce increments. If you have 6 extra ounces of breast milk (you go, mama!), then split the breast milk between breast milk two storage bags at 3 ounces each.
If you are unsure of what your baby’s bottle sizes are, then freezing in 2-3 ounce increments is a good place to start in determining out how much breast milk to store. You want to avoid overfilling breast milk storage bags because you do not want to waste breast milk. Per the CDC, thawed breast milk needs to be used within 24 hours. If you fill a breast milk storage bag to the max 6 ounce capacity but only use 2 ounces of breast milk in 24 hours, then you need to throw out the remaining 4 ounces of your liquid gold. No bueno. Save yourself the heartache and freeze breast milk in small increments while you figure out how to store your breast milk after pumping.
We have tried many, many different storage bags over the years and our recommendation for the best breast milk storage bags are Lansinoh. They are the most popular bags with good reason. We have had the fewest amounts of leaks collectively with Lansinoh bags. And we have tried nearly all of them!
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2. Refrigerate breast milk after pumping to mix with pumped breast milk from a different day
If you only have 1-2 extra ounces of breast milk, it may not make sense to use a breast milk storage bag. In this case, place the extra breast milk in a bottle in the refrigerator until you can add more breast milk to it the next day. Per the CDC, breast milk is fine in the refrigerator for up to four days, so you can combine additional breast milk from a different day, to the original bottle, over a four day span. Make sure to freeze it on day 4 regardless of how many ounces you have to freeze.
The most important thing to remember when combining breast milk from different days is to make sure that the newer breast milk is cooled before combining with the older breast milk. You never want to mix room temperature breast milk with refrigerated or chilled breast milk since the temperature differences can have a negative impact on the nutrients and breast milk microbiome. Place the date of the earliest/oldest breast milk on the breast milk storage bag before freezing it.
3. Save pumped breast milk for bottles at night
If you exclusively pump or share middle of the night feedings with your partner, place your extra breast milk directly into baby’s bottles for her next feed. As we mentioned, breast milk is good in the refrigerator for up to 4 days. You can use that breast milk for baby’s bottles any time over a 4 day span. If you do not use the breast milk within 4 days, freeze it.
Related article: Do I Need to Pump at Night When Baby Sleeps Through The Night?
How do I get breast milk fat off the side of a bottle after pumping?
You have heard that cream rises to the top, right? It’s quite literally the same with breast milk. The fat, or creamy part, of breast milk will rise to the top and sides of whatever type of container it is stored in. For working breastfeeding moms, that means fat will stick to the side of the bottles you pump breast milk in to. Milk fat contains all sorts of nutrients that our babies need, so it’s essential you get the fat out of the breast milk bottles and into baby’s bottles. In order to get breast milk fat off the sides of a bottle, you have a few options:
1. Warm breast milk bottle in hands
In order to get the breast milk fat out of the bottle, you need to warm it. By placing a chilled bottle into your hands and gently rolling it back and forth, the fat will melt thereby making it easy to pour into baby’s bottles or a breast milk storage bag.
2. Run breast milk bottle under warm water
Just like warming the bottle in your hands, you can also speed up the process slightly by running the breast milk bottle under warm water. Make sure the water is warm and not hot. You do not want to actually warm the breast milk. You just want to gently warm the outside of the bottle so that the fat will melt.
3. Gently swirl pumped breast milk bottle
Swirl the bottle gently in circles until all of the fat comes off the sides. This will take a bit longer than warming the bottles like we outlined above. There has been debate for years on how much force breast milk can take. Does shaking breast milk damage it? Yes if your arm has the strength of a paint mixer. No if your arm does not. Since most moms arms do not have that level of strength, it’s probably fine to gently shake a bottle of breast milk to remove breast milk residue from the sides of a bottle. We like to meet in the middle and gently swirl instead of shake. But you do you, and know that your arm is very unlikely to denature breast milk proteins!
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4. Use a bottle spatula to remove breast milk fat
If you deal with pumped breast milk fat sticking to the side of your bottles every day, it may be worth purchasing a bottle spatula. By using a spatula, you can quickly scrape the sides of the bottle and not worry about warming or swirling. Plus, you can get every single drop of breast milk by scraping the sides of the bottle. You can also use bottle spatulas for diaper cream, baby lotion, or concealer for your sleep deprived under eye bags.
How to store pumped breast milk in a deep freezer
If you find that you are consistently pumping more breast milk than your baby needs, you may wonder how else to store breast milk after pumping. You may have an oversupply now, but as baby gets older, you start your period, or some sickness befalls you, your breast milk supply may tank in which case you will need extra breast milk. Placing breast milk in a deep freezer will allow for more dedicated space and provides greater protection in the case of a power outage (deep freezers typically keep things frozen longer than refrigerator freezers).
A few of our moms have tried different deep freezers for breast milk storage. If you don’t currently have one, we recommend this deep freezer for breast milk. The amount of breast milk you intend on freezing and the space you have available will determine what freezer size you should purchase. Deep freezers are not cheap, but the benefit here is that you can use it long after you are done breastfeeding. And it is less costly than a year’s supply of formula. Tell your husband that justifies the price. And getting the breast milk out of the refrigerator freezer will allow more room for pizza and ice cream. 😉
When placing breast milk storage bags in a deep freezer (or any freezer), place them horizontally so they freeze flat. After they freeze, move them into a container such as this to keep your freezer organized. Place the newest bag of milk into the back of the container so that the oldest milk is at the front of the container. You want to use the oldest milk first in order to use it before it loses most of its nutrients (12 months per the CDC). Placing them in a container also makes it easy to remove your breast milk from the freezer should you experience a prolonged power outage.
Alternatively, you can store breast milk storage bags in large gallon Ziploc bags. You can typically store around 50-55 ounces per Ziploc bag. The important thing to remember when storing pumped breast milk in a Ziploc bag is to write the dates you pumped the breast milk on the outside of the bag. This will ensure that you remember to use the frozen breast milk within 12 months. Stack your breast milk “bricks” on top of each other in your freezer to maximize space.
How to use frozen breast milk
If you find that your frozen breast milk stash is becoming quite large, you will want to begin using and rotating it. The CDC recommends using frozen breast milk within 12 months. In order to use frozen stored breast milk after pumping you can:
1. Send all frozen milk to childcare on Monday and freeze the breast milk you pump on Friday.
Use the oldest pumped breast milk from your frozen stash for baby’s bottles on Monday. Use fresh breast milk that you pump at work all week long, and then freeze the breast milk you pump on Friday. By doing this, you will rotate through your frozen stash so that none of the breast milk becomes too old to use.
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2. Send one bottle of frozen milk to childcare each day.
By sending one frozen bottle a day, you will cycle through five bags of breast milk a week. This will ensure that your frozen breast milk stash is used within the one year CDC recommended time frame. Use fresh breast milk for all other bottles.
3. Donate breast milk to a mother in need
If your frozen breast milk stash is larger than you can reasonably rotate through, consider donating a portion of it to a mother in need. Look up your local Eats on Feets chapter, check out the Human Milk 4 Human Babies Facebook page, see if there is local milk bank in your area that accepts donations, or reach out to your local hospital to see if they accept donor milk for babies in the NICU.
Ultimately, find what processes work for you as you figure out how to store breast milk after pumping. What we have outlined here is just a starting guide. Each mom’s situation, breast milk supply, home, etc. is different, so as with every method and process we discuss here on Work Breastfeed Mom, it’s important you find what works for you.
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