With the benefits that breast milk holds for both mother and child, it is no surprise that you would want to save as much of it as possible. As the percentage of working mothers continues to steadily increase, more new moms are needing reliable storage for their breast milk. Have you ever found yourself asking the following question?
How do I keep breast milk cold at work? If you don’t have a refrigerator available at work, the best way to store breast milk is with the combination of special containers designed for holding milk, waterproof labels, ice packs, and insulated coolers.
Containers, labels, coolers, and ice packs. As if you already weren’t busy enough trying to learn the ropes of motherhood.
It can definitely be a lot to keep track of. By the time you finish reading this, you’ll have a better idea of the why’s and how’s of storing breast milk at work.
How To Keep Your Breast Milk Safe At Work
You might be worried about using a community fridge at work. I’ve seen stories that made me cringe where a co-worker saw a mom’s breast milk in the community fridge, didn’t know what it was, and then used it as their coffee creamer.
Other offices have policies where they toss anything in the community fridge at work on Friday afternoon so things are not forgotten and left to rot in the fridge all weekend.
Losing all of that hard work from pumping would be so awful!
If you don’t want to risk your liquid gold with your community fridge at work, or if you do not have a shared fridge in your office, there are a few options.
One creative option to store breast milk at work is to use this tiny mini refrigerator (link to Amazon) that you can keep on your desk.
I loved this mini fridge as a way to keep the milk safely within my control. After I was done pumping I used it to keep a few cans of La Croix at my desk.
The mini refrigerator was also super useful in case I forgot an ice pack.
Another option is to use a breast milk cooler. These are coolers that you can use to keep cool with ice packs that you freeze the night before.

Types of Coolers and Their Benefits
With so many coolers out there, how do you decide which cooler meets your needs? What exactly should you be looking for in a cooler?
The main difference that a cooler designed to carry breast milk has against other coolers is the insulated lining.
Any cooler that has an insulated lining is created to keep what is inside cold for a longer amount of time.
Now, as far as features go, you will want to know how much milk you can carry, if you need to get an ice pack, and if your cooler has the capacity to hold frozen milk.
Check out the table to find more information on the top breast milk coolers and their options.
Personally, I used two different breast milk coolers.
When I first started pumping at work, I pumped into Avent bottles because they attached directly to my Spectra pump. This PackIt freezable cooler was great with lots of room to store bottles because the sides of the cooler served as the ice pack.
Later on, I ended up using a converter so I could pump directly into Dr. Brown bottles. This way, I wouldn’t lose any drops from transferring milk between bottles. (You can read more about that in this article here).
When I wanted to transport my tall Dr. Brown bottles, I found that this cooler worked the best.
The table shows coolers with all of their different options.
Cooler | How many bags/bottles? | Special Features | Ice Pack Included | Cooler Material | Frozen Milk Option |
PackIt Freezable Baby Bottle Cooler | 4- 5oz bottles | Remove divider to increase storage | Freezable gel walls | Nontoxic poly canvas | Between 6-8 hours |
Medela Breast Milk Cooler Set | 4- 5oz bottles | Fits in select Medela breast pump bags | Yes | Microfiber, Plastic | Between 4-5 hours |
Sarah Wells Cold Gold Breast Milk Cooler | 4- 8oz bottles | Additional storage pockets | Yes | Nylon | Up to 24 hours |
Itzy Ritzy Breast Milk Cooler | 3- 8oz bottles | Fits Tall Bottles like Dr. Brown’s | No | Nylon | Up to 24 hours |
Lekebaby Breast Milk Cooler | 6- 5oz bottles | Top and Front open, extra zipper pocket | Yes | Aluminum foil, Oxford fabric | Not recommended |
YARWO Cooler | 6- 9 oz bottles | Extra storage, holds cold or warm milk | Yes | Aluminum foil, Oxford fabric | Not recommended |
V-COOOL Premium Breast Milk Cooler | 6- 5oz bottles | Works as lunch pack and bottle storage | No | Oxford cloth, Aluminum film, PU, Nylon | Not recommended |
Momcozy Insulated Breast Milk Cooler | 4- 8oz bottles | Fits large bottles like Dr. Brown’s, Detachable buckle | No | Insulated tin foil, Composite fabric | Not recommended |
Gogoso Breast Pump Bag | 3 to 5- 5oz bottles | Both a cooler/ breast pump bag, works as a backpack, USB charging pot | No | Polyester | Not recommended |
Tommee Tippee Insulated Bottle Bag & Bottle Cooler | 2- 5 to 9oz bottles (depends on brand) | Keep bottles at different temperatures | No | Synthetic | Not recommended |
Breast Milk Containers
You now have an idea about the type of cooler you want but next is to figure out what type of containers to use to hold the breast milk.
Washing your hands with soap and water before handling breast milk is highly recommended to keep germs to a minimum.
Breast milk can then be stored in the following containers:
- Capped food-grade glass container- reusable, no plastic, you can find DIY kits for certain sizes to be turned into baby bottles
- BPA-free plastic baby bottles- reusable, no need for extra DIY, exact amount shown on bottle
- Breast milk storage bags- stores more compactly, conveniently use the bag and dispose, easy to label, amounts shown on bags
When using bottles or glass containers to store breast milk, make sure that you have a lid that fits your container to avoid spillage.
Breast milk bags were designed for single use and will include a double-zipper seal. Make sure to securely seal bags after filling them and to never overfill the bags.
Remember: Breast milk should not be stored in general use plastic bags or disposable bottle liners. These bags tend to tear when frozen and do not allow you to accurately document the amount in the bag.
How Much Breast Milk Should I Store in Each Bag?
After deciding on the type of container, you now must decide how much breast milk to put in each container.
While it may seem best to fill each container to the brim, Mayo Clinic suggests that once you thaw breast milk, it is best to use it within 24 hours.
The best way to determine how much breast milk you should store in each container is to store enough for one feeding.
If your baby drinks around six ounces then storing 6 ounces per container will be a good starting place. You can also have “extra” bags that hold between 1-2 ounces in case you have an extra hungry baby during a feeding.
When storing breast milk, you can store it in the fridge for up to five days and in the freezer for up to six months.
We have included a reference list of the different storage methods along with their timeframes below.
- Freezer- Stores for up to 6 months
- Refrigerator- Stores for up to 5 days
- Breast milk cooler- Stores for up to 1 day
- Room temperature- Stores for up to 4-6 hours
New vs. Old Breast Milk
Depending on how long you have kept your breast milk, you may notice changes in the color or even the composition of your milk.
As your baby gets older, your breast milk will start to adjust to meet your baby’s needs.
When you’re deciding to mix newer milk with older milk, remember to cool it down in the refrigerator so that the frozen milk does not start to thaw.
Breast milk that has been frozen should be labeled with the date in order to effectively use all of your milk within the recommended time period.
Pub Med has reported that the amount of Vitamin C steadily decreases the longer the breast milk is kept in the refrigerator or freezer.
Keeping this in mind, it is best to use your breast milk from oldest to newest in order to get the most nutrition out of each bottle.
Tip: Gently warm milk under warm running water to thoroughly thaw before use. Though this method may take longer, it evenly warms the milk with out causing some parts to get to hot or to stay cold.
After you have successfully thawed your breast milk, always check the temperature on the inside of your wrist. If the milk feels hot then allow for it to cool down to room temperature before feeding your baby.
You may also notice that the thawed milk has a slight change in color. This is very normal as the milk and fat content tend to separate once frozen.
If you think that the milk may have spoiled, you can check for chunks that don’t mix in and smell. Breast milk does smell different from other milk but it will smell sour when it goes bad.
Breast Milk Color
You may notice that there have been several different colors of your breast milk. Even if the breast milk is not white in color, it doesn’t mean that it has gone rancid. Check out the common colors and their reasons below:
- Green- Caused by eating greed food dye, vitamin supplements, or green foods.
- Pink, Orange, Red- Caused by eating foods these colors, or that have red, yellow, or orange food dye.
- Brown, Rusty, Blood-Tinged- Causes may be cracked nipples or by blood mixing in with the breast milk. Bleeding will usually go away after a few days. If bleeding doesn’t go away, consult your doctor.
- White, Yellow- Common colors, may be caused by eating yellow- or orange-pigmented food.
- Black- Caused by the certain antibiotics, including Minocin. Remember to consult your doctor about breast feeding before taking any medications.
Breast milk will change as your baby grows, after being frozen, or after being refrigerated.
If you are concerned with the color, amount, or composition of your breast milk, you should schedule a meeting with your doctor to discuss possible solutions.
Let’s Sum it Up
Being a new mom brings on many new joyful moments and times that may make you feel like hiding under a blanket. You can now feel more confident in how to decide between breast milk coolers and the proper ways of storing breast milk.
Now, just remember:
- Not all breast milk coolers were created equal.
- Remember to check if the cooler you chose needs an ice pack.
- Check the recommended bottle sizes for your cooler
- Store enough breast milk for one complete feeding
- Breast milk may come in different colors depending on what you eat
Must-Have Pumping Gear
Hear are a few of my favorite pumping items that made my life so much easier.
- This is the best pumping bra that is actually comfortable to wear all day long (the Sublime version). Use this link and code Lisa15 for a special discount on your purchase!
- Try the Chocolate Fudge flavor of this yummy milk-boosting protein powder.
- Click here for the best deal on the WillowGo pump!
- These are the best baby bottle labels that will not wash off or wear off. The pineapple design and the whale design are two of my favorites.
- My favorite pumping bag that is roomy enough for my pump, a laptop, a cooler, and a lunch bag. They have so many cute colors and prints but I really love the Floral print.
- These custom baby name onesies I found on Etsy are so adorable I ended up buying them in two different colors. The shop even has a really cute matching mommy and me set.
- I used this tiny mini fridge (link to Amazon) near my pumping station at home so I didn’t have to trek to the kitchen after a middle of the night pumping session.
- This postpartum care box has a couple of my must-have items for the first few months after baby arrives. The tubes that help with engorgement provide so much relief.
- If you enjoyed this article, you can help support this blog by buying me a coffee here. Your support is very much appreciated!
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