How To Store, Thaw And Heat Breast Milk

Posted in Breastfeeding Advice.

Breast milk storage: How to store, thaw and heat breast milk | Mum's Grapevine

It’s called liquid gold with good reason – breastmilk is precious stuff and needs to be stored properly to make sure it keeps all of its milky goodness.

Whether you’re hand expressing or using a breast pump the rules for storing, thawing and heating breastmilk are all about keeping breastmilk safe for bub to drink. Breastmilk can be stored at room temperature, in the fridge or freezer, but timing is key. And what about leftover breastmilk – can it be reused if bub hasn’t finished the bottle?

Here’s everything you need to know about breast milk storage, thawing and warming.

How to store breast milk

Breast Milk Storage

You’ve pumped and now you need to store, so what’s the best way to keep breast milk safely stowed until you want to give it to bub?

Breast milk can be kept in glass or plastic containers, or in resealable plastic bags. You can directly pump into some of these storage containers, and then simply seal and store at room temperature, in the fridge or the freezer.

Breast milk storage bags

Breast milk storage bags are perfect if you’re planning on freezing breast as they can be stored flat, taking up very little room.


Breast milk storage bags

Pigeon Breast Milk Storage Bags ($22.95)

Pre-sterilised with an easy-pour spout, Pigeon breast milk storage bags also have a double zip seal to stop leaks.

Buy Now button linking to Chemist Direct


Medela Breast Milk Storage Bags

Medela Breast Milk Storage Bags ($15.99)

Hygienically pre-sealed and ready to use, these bags have a double zipper seal and can lay flat once full.

Buy Now button linking to Amazon

Dr. DuDu

Dr DuDu Breast Milk Storage Bags

Dr. DuDu Breast Milk Storage Bags (22.95)

Self-standing and with an easy pour spout at the bottom of the bag, these also feature an easy-tear design.

Buy Now button linking to Amazon


Lansinoh Breast Milk Storage Bags

Lansinoh Breast Milk Storage Bags ($19.95)

Pre-sterilised with a double zipper seal to stop leaks, this pack also comes with breast pump adapters so you can pump directly into the bags.

Buy Now button linking to Amazon


Unimom Breast Milk Storage Bags

Unimom Breast Milk Storage Bags ($18.85)

Self-standing bags that are sterilised and freezer safe.

Buy Now button linking to Amazon


NUK Breast Milk Storage Bags

NUK Breast Milk Storage Bags ($19.95)

Leak-proof double zipper seal bags that are durable, freezer safe and self-standing.

Buy Now button linking to Baby Bunting

Breast Milk Storage Bottles

Pretty much a one-stop-shop for breastmilk storage – pump directly into the bottles then pop on the lid to either freeze or store breastmilk until it’s ready for use.

MedelaBreast milk storage bottlesMedela Breast Milk Storage Bottles ($17.95)

These can be tossed into the dishwasher for washing and are made from BPA free plastic.

Buy Now button linking to Chemist Direct


Pigeon Breast Milk Storage Bottles

Pigeon Breast Milk Storage Bottles ($14.96)

Handy for storing breast milk in the fridge or freezer and holds 150ml.

Buy Now button linking to Baby Bunting

Breast milk storage cups

Stackable and sturdy, breastmilk storage cups can be used in the fridge or freezer.


Breast milk storage cups

Avent Breast Milk Storage Cups ($16.95)

They come pre-sterilised and can be re-sterilised up to four times before they need to be thrown out or recycled. Use the adapter to express directly into the cups then seal with the lid. These nifty containers can also be used to store baby food.

Buy Now button linking to Chemist Direct

How long can breast milk be stored for?

It all depends on whether the freshly expressed milk is being kept at room temperature, in the fridge or frozen.

At room temperature: Freshly expressed milk can be kept at room temperature that’s no more than 26ºC for six to eight hours. But if you can pop it in the fridge, do so.

In the fridge: for no more than 72 hours at 5°C or lower. Pop it in the back of the fridge where it’s the coldest.

In the freezer:

  • For two weeks in the ice or freezer compartment inside a fridge. (-15°C)
  • For 3 months in the freezer section of a refrigerator with a separate door. (–18°C)
  • For 6 to 12 months in a deep freezer that’s opened infrequently. (–20°C)

Remember that breast milk needs to be stored in a container that’s been sterilised, and that includes using a breastpump that has been properly cleaned.

How do you defrost frozen breast milk?

How to store breastmilk in the freezer

Breastmilk should be defrosted in the fridge – just pop it straight into the fridge after taking it from the freezer and leave it until it’s completely thawed. Make sure you use it straight away once it’s defrosted. If bub is ok taking cold milk, it can be given cold.

Just remember once it’s been thawed it can’t be refrozen. If it’s been thawed, but not warmed, it can be kept for four hours or less in the fridge. You can use leftover breast milk to make a lush breastmilk bum balm for baby.

How do you warm breast milk?

You can’t use a microwave to heat up or defrost breast milk because it can create hotspots that burn bub’s mouth, and it kills some of the goodies in the milk. The easiest and safest way is just to place the storage bag or bottle with breast milk into a container with some warm water and let it gently heat up to body temperature.

Once the milk is warm, swirl it so it’s mixed and just test it to make sure it’s not too hot.

Can I keep breast milk that’s been thawed?

Breast milk that was frozen and thawed in the fridge, but not warmed:

  • Can keep at room temperature for up to four hours (so the next feed).
  • Can be stored in the fridge for 24 hours.
  • Can’t be refrozen.

Breast milk that’s been thawed outside the fridge in warm water:

  • Can only be kept at room temperature until the end of the feed.
  • Can be kept in the fridge for up to four hours (the next feed).
  • Can’t be refrozen.

Bub has begun the feed:

  • Can only be kept until the end of that feed, then must be thrown out.
  • Can’t be put back in the fridge.
  • Can’t be refrozen.

Can I add freshly expressed breast milk to milk expressed earlier?

Yes, just make sure you cool the freshly expressed milk in the fridge before you add it to previously expressed chilled or frozen breast milk.

How should I transport expressed breast milk?

Just keep in mind the temperature of the breast milk while it’s being transported. Pop the expressed milk into an insulated container like a cooler bag or esky, and put a freezer brick with it. This works for freshly expressed, out of the fridge or frozen.

If it’s thawed, just make sure it’s used within four hours, and don’t refreeze. As soon as you get to where you’re going, put the milk into a fridge.

Sources: Health Direct, Australian Breastfeeding Association, Raising Children
Featured image: Medela

Read next …

Now you know how to use your expressed breast milk, here’s some other helpful info about this liquid gold:

Join our Facebook pregnancy groups

Expecting a baby? Join one of the closed Mum’s Grapevine pregnancy Facebook groups for non-judgemental support from other mums due at the same time as you. We’re chatting at all times of the day and night, so if pregnancy insomnia got you tossing and turning, make a cuppa and come on in.

Click below and join your group today.

Share On