How to Store Breast Milk?

While breast pumping is a great way to relieve discomfort, and ensure that you can continue to provide nutrition for your baby via natural breast milk even when you’re separated from your baby, there are important things to remember when it comes to storing your expressed milk. Since it is unprocessed and all natural, care must be taken to ensure that it keeps well.

Which breast milk storage method is best?


When it comes to storing expressed milk, the best method for you will vary based on your individual requirements. Depending on how much milk you are looking to store, how often you express and how much you are able to pump, how long you intend to keep  in storage, when you intend to use it and how much – all these factors will determine what is the best pumped breast milk storage method for you.

  • Store at room temperature (Below 25o C) for up to six hours
  • In a cold box (with ice packs) for up to 24 hours
  • In a refrigerator (under 4o C) for up to five days – keep away from meat, eggs or raw foods
  • In a freezer for up to two weeks
  • In a deep freezer (-18o C or lower) for up to six months

Depending on your usage and milk availability, find what option works best for you for expressed milk storage. Keep the following in mind to ensure safe breast milk storage at all times

  • Use sterilized plastic containers or breast milk bags, not glass
  • Label and date stored milk, use oldest ones first
  • Keep breast pumps and bottles clean at all times
  • Wash hands before expressing and handling breastmilk

Store carefully and keep containers sterilized

Keep your expressed milk fresh by storing it in sterilised feeding bottles. Philips AVENT feeding bottles all come with secure tops to seal in the freshness and make breast milk storage fuss free. 

Keep it in the fridge to use quickly, and in the freezer for later

Your expressed milk can be stored in the fridge for up to 24 hours, or in the freezer for up to 3 months. Place it on the fridge shelf, rather than in the door, to ensure it is kept at a constant temperature.

Don’t thaw more than half a day in advance 

After thawing, frozen breastmilk can be stored in the fridge for up to 12 hours. You can also use disposable cups for storing milk, but don’t forget to write the date on it so you know when it was expressed.

How to warm stored breast milk


If you’re using a freezer or deep freezer for pumped breast milk storage, thaw your stored milk in the fridge in advance. Do not use a microwave or stove to rapidly thaw milk as it may burn or warm unevenly causing hot and cold spots that can cause serious discomfort to your baby. Once thawed, there are a few different methods to warm breast milk optimally. You can place the bottle or bag in a container of warm water – this method is slow but the gradual warming ensures consistent warming and fewer hotspots. If not done right however, the milk may not be warmed sufficiently and may require multiple tries. Warming on a stove is another option – this method is quicker, but is labour intensive and requires vigilance. It is very easy to overheat the milk, which will cause significant distress to the baby. The best way to warm after storing expressed milk is to use a bottle warmer like the Philips Avent bottle warmer – this method is hassle free and ensures  consistent warming throughout, so you can feed without worrying about hot or cold spots. This method is also quick and easy, warming up a bottle of milk in minutes at the touch of a button.

Avoid using a microwave

Make sure you don’t use a microwave to defrost or warm expressed milk, as hot spots could burn your baby.

How to check stored breast milk


When storing expressed milk, especially long term in the freezer, it can be difficult to ensure that the milk is still usable. Breast milk is not the same as the dairy milk that we consume regularly, so it can be difficult to judge based on the normal criteria whether it is good or not. There are three main things that must be checked to ensure that stored breast milk is still usable for feeding

How long it’s been stored


Do not store milk past the recommended guidelines for each storage method. If milk is stored past the time it is generally considered usable, do not take the risk – dispose of it.

How it looks


Breast milk naturally separates over time, with fat rising and water falling to the bottom. A gentle swirl of the bag or bottle will recombine and mix the fat and water. If breast milk remains separated or chunky after attempting to mix it, it has likely gone bad and should be disposed of. Breast milk also naturally has a variety of colours, so don’t be alarmed if it is yellow, off white, slightly blue or slightly orange.

How it smells


There is no single “correct” way for breast milk to smell, as a variety of factors can impact the way it smells, including mom’s diet and general health. It is important however to smell breast milk to check if it’s okay – if there is even a hint of rancid scent, or sourness, it is better to dispose of it than to risk giving spoiled milk to your baby.

How it tastes


Similar to taste and look, there is no one single way that breast milk should or shouldn’t taste. Thaw a small portion and have a little taste – if there is any hint of rancidness or sourness, dispose of the milk.

Get rid of the leftovers

It’s recommended that you throw away any milk that's left in your baby's bottle after each feed.


Please be aware that the information given in these articles is only intended as general advice and should in no way be taken as a substitute for professional medical advice. If you or your family or your child is suffering from symptoms or conditions which are severe or persistent or you need specific medical advice, please seek professional medical assistance. Philips AVENT cannot be held responsible for any damages that result from the use of the information provided on this website.

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