What You Need To Know About Reheating Breast Milk

Can breast milk be reheated after it’s been stored in the fridge or freezer? What’s the best way to reheat breast milk?

If you choose to pump your breast milk, you’ve probably asked these questions. Many women choose to pump and store their breast milk because they’re looking for greater flexibility in their feeding schedule.

However, that comes with some technical requirements, like keeping your breast milk cool while it’s stored, and reheating it properly to ensure it’s safe for your baby’s sensitive stomach.

Managing all the small details of breastfeeding may initially seem like a lot. However, once you learn the basic facts and how-tos of reheating breast milk, it will become second nature.

There’s only one way to get this process started — keep on reading!

The Benefits of Breast Milk

Doctors and scientists agree breast milk is very beneficial for your baby’s growth. You’ve probably heard it yourself from other mothers, “breast is best!”

This is because breast milk provides the perfect combination of nutrients, vitamins, and antibodies your baby needs to grow healthy and strong. Babies who are fed breast milk also experience fewer hospital visits and a decreased risk for Sudden Infant Death Syndrome (source).

However, many mothers struggle to breastfeed. Some of this can be attributed to the time it takes to breastfeed or to pump breast milk. Being able to store breast milk and reheat it when it’s needed can help busy moms continue to provide the benefits of breast milk to their babies.

How Should I Store Breast Milk?

If your baby doesn’t finish a bottle, or if you choose to pump your breast milk, it needs to be stored in a cold place until you’re ready to use it again. The methods you use to store your breast milk should be determined by when you plan to use it next.

Breast Milk Containers

There are many containers specifically created to store breast milk. They include:

You can even purchase entire kits that contain a cooler bag, a breast pump, and storage containers. Avoid using regular plastic bags, as they can burst when frozen and the plastic may leech into the breast milk.

Best Temperature To Store Breast Milk

It’s important to store your breast milk at the correct temperature to prevent bacteria from growing, especially if you’re storing a half-used bottle that’s been exposed to saliva.

The Centers for Disease Control and Prevention came up with these helpful guidelines to ensure safe storage (source):

  • Fresh breast milk: Freshly pumped breast milk can be stored in a 40°F refrigerator for up to 4 days or in a 0°F freezer for up to six months.
  • Thawed breast milk: Thawed breast milk can be placed back in the refrigerator for up to 1 day. It should never be refrozen and reused.
  • Unfinished bottle: You need to reuse breast milk from a bottle your baby has fed from within 2 hours of the feeding. It can be stored right on the counter or in the fridge.After 2 hours, dispose of it. The saliva will start breaking down the enzymes in the milk and bacteria can grow.

Timing Tip

You may want to get a storage system that allows you to keep track of how long breast milk has been in your freezer or fridge. You can also develop your own using post-its, chalk markers, or whatever you find easiest.

Why Reheat Breast Milk?

The fact is, you don’t need to reheat breast milk. Your breast milk does not need to reach a certain temperature after it’s been thawed to be usable. As long as it has reached a liquid state, it’s safe for your baby to ingest.

However, many babies prefer warm breast milk. Reheating the breast milk can take off the cold edge, making for a more comfortable feeding experience. Warm breast milk can also help soothe and calm babies during feedings.

How Do I Reheat Breast Milk?

Reheating breast milk is simple. Just follow these three steps:

  • Thaw: Thaw your breast milk in the fridge overnight. It should reach a fully liquid state. Do not thaw frozen breast milk at room temperature.
  • Warm: Place the thawed breast milk into a bowl of warm water for 20 minutes.
  • Swirl: Swirl the milk inside of the bottle to evenly distribute the heat and reconstitute it.

The thing you need to be most careful of is overheating. If breast milk becomes too hot, it not only loses some of its beneficial nutrients, but can burn your baby’s tongue. The bottle, especially if it’s glass, can also overheat and burn your baby’s skin when they touch it.

Pro tip

Never reheat breast milk in the microwave. Microwaves heat unevenly, which could cause hot spots. You will also have a hard time ensuring your breast milk has not become too hot.

Reheating Breast Milk On The Go

Unless you plan on never leaving the house with your baby there will like be times when you need to feed them on-the-go without the comforts of home. While some mothers choose to breastfeed in public, many choose to bring bottles of breast milk with them.

Here are a few ideas on how to keep the breast milk flowing, no matter where you’re going.

1. Bring thawed bottles

Thawed breast milk can be kept at room temperature for two hours. If your outing is short, just store the thawed bottles in your favorite diaper bag.

2. Bring a cooler

Medela Breast Milk Cooler Set

If you plan to be out for an extended period of time, consider a more long-lasting storage solution.

If your baby will drink cold breast milk, carry the bottles in a cooler such as this one. It will keep your breast milk safe for up to twelve hours.

3. Bring a travel warmer

Tommee Tippee Travel Bottle and Food Warmer

If your baby prefers warmed breast milk, keep the bottles in the cooler but use a travel bottle warmer to heat it up. You can also run the bottle under hot water in a bathroom or ask a restaurant waiter for a glass of hot water.

Avoid keeping breast milk in a hot car and make sure to keep track of how long bottles have been sitting out at room temperature to avoid spoiling. Always check the temperature before giving to your baby.

Checking Breast Milk Temperature

MilkChecker Automatic Milk Temperature Monitor Ideal for Measuring Breast Milk &...

The easiest way to test the temperature of breast milk is to place a few drops on the inside of your wrist. It should be slightly warm, but not hot. If you believe it’s too hot, imagine the effect on your baby’s sensitive skin!

You can also purchase a small temperature checker designed with bottles in mind. All you have to do is place the bottle on the small scale and the device will tell you the temperature of your bottle.

The ideal temperature for breast milk is approximately 98.6°F, just around the average body temperature (source).

Don’t put your finger in the breast milk or place the bottle to your lips — this will increase the risk of passing germs on to your baby.

What Is A Bottle Warmer?

You may have heard about bottle warmers, special machines designed to make thawing and warming milk easy. Do you really need one?

If your baby isn’t a picky eater, bottle warmers will likely not make much of a difference to them. However, if your baby is finicky about bottle temperature, a bottle warmer may be useful for warming and circulating the breast milk in one easy step.

You’ll want to do some research before purchasing a bottle warmer. Some bottle warmers are not recommended for breast milk, and are better for formula.

Bottle warmers can also be a good investment if you plan on warming baby food as your little one grows.

Pro tip

A major concern with bottle warmers is overheating. Make sure to test out your settings and find how hot your bottle warmer runs.
Related Reading:
How to Warm Baby Bottles: 4 Quick & Safe Methods You Can Use

Overheating Breast Milk

The major concern with overheating breast milk is burning your baby’s sensitive mouth and skin as they try to drink the milk or touch the hot bottle.

Overheating also damages the breast milk, destroying many of the important nutrients your baby needs (source).

If you accidentally overheat a bottle of breast milk, you can cool it down and it will be safe for your baby to drink. However, you want to make sure the breast milk is used within two hours.

Does Reheating Change Breast Milk?

Your breast milk may look slightly different after you store it and when you reheat it.

Once milk is refrigerated or frozen, it may separate. The fat in the milk travels to the top while the liquid sinks to the bottom.

After reheating, it’s normal for your breast milk to change color. It may take on a blue, yellow, or even brown hue (source). This discoloration is not generally a sign something is wrong with your breast milk and is still safe for your baby to drink.

When Breast Milk Goes Bad

There are times when a bottle may have been left out too long, or that thawed portion of breast milk in the fridge just doesn’t seem right. In these situations, it’s key to remember that breast milk can go bad.

There are a few key identifiers to spotting spoiled breast milk.

1. Curdling

Just as with cow milk, the most obvious sign of spoiling will be a bad odor and curdling. Even though your breast milk may separate, it should easily mix back together. If it does not, it may be bad.

2. Sour taste

If you’re concerned about your breast milk and these other signs are unclear, taste it. If it has gone bad, It will have a strong sour taste.

3. Play it safe

If you’re unsure as to whether or not the breast milk in question has gone bad, play it safe and throw it out. Make sure to keep track of how old your breast milk is. Many freezer bags and bottles have a space for you to write the date and time.

Use the breast milk with the oldest date first. Sort them in your freezer so they are right in front and ready to be taken out first.

Pro tip

Make sure you clean your breast pump and all bottles properly. If not properly cleaned, old breast milk stuck in the bottle or pump can contaminate new breast milk.
Related Reading:
How to Avoid a Bottle Full of Germs with a Baby Bottle Sterilizer

Your Best Breast Milk Practices

By following these safety rules, you can reheat breast milk easily, ensuring your feeding schedule is more convenient and your little one is nourished.

By following storage guidelines and some unique tools like coolers and bottle warmers, you can store and reheat breast milk with ease!

Do you have tips or suggestions for reheating breast milk? Share your knowledge in the comments below!

If you know a mom with questions about reheating breast milk, please share this article with them.

Related Reading:

Leave a Comment