Breast milk can be turned into a lightweight, shelf-stable powder through a process called freeze-drying, also known as lyophilisation.
Unlike simply dehydrating breast milk with heat, freeze-drying first freezes the milk and then removes water under carefully controlled vacuum conditions. The resulting freeze-dried breast milk powder can later be reconstituted with water when it is needed.
For families with a freezer full of expressed breast milk, turning breast milk into powder can make their milk significantly easier to store, transport and use while reducing reliance on freezer space. It can offer extra convenience for a mum who is pumping regularly, returning to work, travelling or simply trying to make more room in the freezer.
At Nourishy, we professionally freeze-dry each family's own breast milk individually in our Brisbane facility. The milk you send us is the milk that is returned to you as powder.
Can Breast Milk Be Turned Into Powder?
Yes. Breast milk can be converted from frozen liquid milk into a dry powder using freeze-drying.
During professional freeze-drying, frozen breast milk is placed under vacuum and water is gradually removed through sublimation. This means frozen water changes from ice directly into water vapour rather than first becoming liquid.
Once sufficient moisture has been removed and the milk has reached the required parameters, the dried breast milk can be converted into powder and packaged for storage.
The process does not add formula, preservatives or other ingredients to the breast milk.
With Nourishy, the finished product has one ingredient: your breast milk.
How Is Breast Milk Turned Into Powder?
Turning breast milk into powder professionally involves considerably more than simply drying milk. At Nourishy, the process broadly involves the following stages.
1. Your Frozen Breast Milk Arrives at Nourishy
Families can send their frozen breast milk to Nourishy using one of our specialised shipping kits or use an available drop-off option. You can learn more about both options in our How It Works guide.
When the milk arrives at our Brisbane facility, it is checked, logged and individually tracked.
Each customer's breast milk is processed separately so that their milk remains their own throughout the process.
2. The Breast Milk Is Prepared for Freeze-Drying
The frozen breast milk is prepared for the freeze-drying cycle using Nourishy's processing system.
We use vapour-permeable processing pouches rather than placing breast milk directly onto shared open trays or bowls.
This forms part of our SafeDry® processing approach and helps maintain separation between individual customer orders during processing. You can read more about our approach in Is Freeze-Dried Breast Milk Safe?
3. The Milk Is Freeze-Dried Under Vacuum
The breast milk remains frozen while the freeze dryer reduces the surrounding pressure.
Under these conditions, ice within the milk undergoes sublimation and leaves the frozen milk as vapour.
This gradually removes the water that previously made up most of the liquid breast milk.
Freeze-drying differs fundamentally from conventional heat-based dehydration because the water is removed from the milk while it remains frozen during the primary drying process.
4. Drying Is Completed
Removing visible ice isn't enough to establish that freeze-drying is complete.
One important measurement used in assessing a dried food product is water activity.
Water activity describes how much water is available within a product to support microbial growth and other reactions. It is different from simply measuring the percentage of water remaining.
At Nourishy water activity is tested as part of our processing and quality-control system.
5. The Freeze-Dried Milk Is Turned Into Powder
Once drying has been completed, the freeze-dried breast milk has a dry, lightweight structure.
It can then be carefully converted into a powder suitable for packaging and later reconstitution.
Depending on the packaging option selected, Nourishy can return breast milk in individual Single-Feed pouches, larger Multi-Feed pouches, or a mix of both. This gives families flexibility in how they prepare milk for a feed, whether at home, at daycare or while travelling with a bottle.
6. The Powdered Breast Milk Is Packaged
Producing dry breast milk is only part of creating a shelf-stable product.
Moisture and oxygen exposure after freeze-drying can affect the stability of dried milk, which makes the packaging system important too.
Nourishy uses high-barrier storage pouches designed to protect the freeze-dried breast milk during storage. Our storage packaging has also undergone independent water vapour transmission rate testing.
When professionally processed, sealed in its original Nourishy packaging and stored according to our instructions, Nourishy freeze-dried breast milk has a shelf life of up to three years.
Is Powdered Breast Milk the Same as Baby Formula?
No. Freeze-dried breast milk powder and infant formula are fundamentally different products.
Infant formula is manufactured from a formulated combination of ingredients designed to provide infant nutrition.
When a mother's own breast milk is professionally freeze-dried, the starting material is her expressed breast milk. Freeze-drying removes water from that milk so that it can be stored in a dry form.
At Nourishy, we do not replace the breast milk with another product or mix different mothers' milk together.
The powder returned to a Nourishy customer comes from their own breast milk.
Why Turn Breast Milk Into Powder?
Families choose to turn breast milk into powder for many different reasons.
Easier Storage
Frozen breast milk can quickly occupy significant freezer space, particularly for a mum who is pumping regularly and building a substantial milk stash.
Removing most of the water substantially reduces the weight and storage requirements of the milk, making a large breast milk stash considerably easier to manage.
Travelling With Breast Milk
Travelling with a large quantity of frozen breast milk can require coolers, ice or dry ice and careful management of temperature throughout the journey.
Freeze-dried breast milk is much easier to transport because it does not need to remain frozen while it stays sealed and is stored according to the applicable instructions.
This can make powdered breast milk particularly useful for holidays, interstate travel and families travelling internationally.
Returning to Work or Daycare
Individual pouches can make expressed breast milk easier to transport and prepare away from home.
Instead of transporting frozen bags of milk each day, parents can take the required amount of freeze-dried milk and reconstitute it when needed. For mums balancing pumping, work and daycare, this can make preparing a breast milk bottle more convenient.
Long-Term Breast Milk Storage
Frozen breast milk remains dependent on continuous freezer storage.
Professionally freeze-dried breast milk can provide another preservation option for families who want to retain their expressed milk for longer-term use.
Nourishy's validated process and packaging provide a shelf life of up to three years when the powder remains sealed and is stored correctly.
Emergency and Backup Milk
Some parents choose to keep freeze-dried milk available as a backup supply.
Because the sealed powder does not require freezer storage, it can provide another way to preserve part of a breast milk stash for future use and provide additional convenience when plans change unexpectedly.
Does Turning Breast Milk Into Powder Change Its Nutritional Value?
Freeze-drying is widely used when heat-sensitive biological and food materials need to be preserved in a dry state.
Research into human milk suggests that many important nutrients and bioactive components can be retained following freeze-drying, although freeze-drying should not be described as leaving every component completely unchanged.
Human milk is complex and contains fats, proteins, carbohydrates and many other components, including naturally occurring enzymes. The final composition depends on the composition of the mother's original milk, which naturally varies between mothers and across lactation.
This is one reason Nourishy processes each mother's breast milk individually rather than pooling milk between customers.
Families who want more information about the nutrients in their own milk can also choose nutritional analysis as an optional service.
Does Freeze-Drying Sterilise Breast Milk?
No.
Freeze-drying should not be considered a sterilisation process.
Professional hygiene, handling, processing controls, water activity and appropriate packaging therefore remain important parts of the overall process.
This is also why turning breast milk into powder involves more than simply owning a freeze dryer.
Can You Freeze-Dry Breast Milk at Home?
Domestic freeze dryers are available, so technically breast milk can be placed into a home freeze dryer.
However, producing a dry powder is not the same thing as establishing a safe, validated shelf life.
Important considerations include:
- hygienic milk handling;
- prevention of cross-contamination;
- validated freeze-drying parameters;
- determining when drying is actually complete;
- water activity;
- appropriate high-barrier packaging;
- moisture and oxygen exposure after processing; and
- appropriate storage conditions.
Without validated processing and packaging, a particular shelf life should not simply be assumed because the breast milk appears dry.
For families wanting breast milk professionally converted into powder for longer-term storage, these controls are an important distinction between professional processing and DIY freeze-drying.
How Long Does Powdered Breast Milk Last?
Shelf life depends on how the breast milk was freeze-dried, its water activity, how it was packaged and how it is stored.
It isn't possible to assign the same shelf life to every freeze-dried breast milk product simply because it has been turned into powder.
With Nourishy's professional process, water-activity testing, validated packaging and recommended storage conditions, sealed freeze-dried breast milk has a shelf life of up to three years.
Once a Multi-Feed pouch is opened, Nourishy recommends using the contents within 30 days and following the applicable storage instructions.
For a deeper explanation of storage conditions, packaging and water activity, read How Long Does Freeze-Dried Breast Milk Last? Shelf Life & Storage Guide.
How Do You Turn Powdered Breast Milk Back Into Liquid Milk?
Freeze-dried breast milk can be reconstituted by adding the appropriate amount of water back to the powder.
The quantity of water removed during processing provides the basis for returning the milk to its liquid form.
Once reconstituted, the milk can be prepared for feeding in an appropriate bottle or feeding vessel and should be treated as liquid breast milk rather than as a shelf-stable powder. Follow appropriate breast milk handling guidance after reconstitution.
The shelf-stable benefit applies to the correctly stored dry product before reconstitution.
Can You Turn Previously Frozen Breast Milk Into Powder?
Yes. In fact, frozen expressed breast milk is what families generally send to Nourishy for freeze-drying.
This means parents don't need to start a new breast milk stash specifically for freeze-drying. Milk a mum has already expressed while pumping and stored in the freezer may be suitable for processing.
Its previous storage and handling history still matters, however. Freeze-drying does not reverse changes that occurred because milk was improperly stored before processing.
What About High-Lipase Breast Milk?
Some expressed breast milk develops a noticeable soapy, metallic or otherwise altered flavour during storage.
This is commonly described by parents as 'high-lipase breast milk', although the mechanisms responsible for stored-milk flavour changes can be more complex than simply having unusually high levels of lipase. Lipase itself is one of the naturally occurring enzymes found in human milk.
Freeze-drying changes the physical environment of the milk by removing water while it is stored as a dry product.
Some Nourishy families whose babies previously rejected stored milk because of flavour changes have reported improved acceptance after their milk was professionally freeze-dried and reconstituted.
However, freeze-drying should not be presented as a guaranteed way of reversing flavour changes that have already occurred.
Read our complete guide to high lipase milk for more information about taste changes, storage and freeze-drying.
Professional Breast Milk Freeze-Drying in Australia
Nourishy provides professional breast milk freeze-drying for families across Australia.
Families can either use one of our specialised shipping kits to send their frozen milk to our Brisbane facility or use an available milk drop-off location. See how Nourishy's breast milk freeze-drying service works.
Every customer order is individually logged, tracked and processed.
Our process includes:
- individual processing of your breast milk;
- SafeDry® vapour-permeable processing pouches;
- controlled freeze-drying cycles developed for human milk;
- water activity testing;
- high-barrier storage packaging;
- independent packaging validation; and
- a shelf life of up to three years when correctly processed, sealed and stored.
The goal is simple: turn the breast milk you've worked hard to express into a convenient powder while keeping it 100% your own milk.
Frequently Asked Questions
Can breast milk really be made into powder?
Yes. Freeze-drying removes water from frozen breast milk under vacuum, leaving dried milk that can be converted into powder and later reconstituted with water.
What is the process called when breast milk is turned into powder?
The process is called freeze-drying, or lyophilisation. It involves freezing the breast milk and removing water primarily through sublimation under reduced pressure.
Is powdered breast milk formula?
No. Freeze-dried breast milk is derived from expressed human milk. Infant formula is a separately manufactured and formulated product.
Can frozen breast milk be turned into powder?
Yes. Frozen expressed breast milk can be professionally freeze-dried and converted into powder, including milk that has previously been expressed through pumping and stored appropriately.
Does powdered breast milk need refrigeration?
Properly processed and packaged Nourishy freeze-dried breast milk does not require refrigeration while it remains dry, sealed and stored according to our instructions. Once reconstituted, it should be handled as liquid breast milk.
How long can freeze-dried breast milk powder be stored?
Nourishy freeze-dried breast milk has a shelf life of up to three years when professionally processed, sealed in the original packaging and stored according to our instructions.
Can I turn my own breast milk into powder in Australia?
Yes. Nourishy professionally freeze-dries customers' own frozen breast milk at our Brisbane facility and accepts milk from families throughout Australia through shipping kits and available drop-off options.
Ready to Turn Your Breast Milk Into Powder?
If your freezer is overflowing with expressed milk, you're planning to travel, or you'd simply like a more convenient way to preserve your breast milk stash, professional freeze-drying can turn your frozen milk into lightweight, shelf-stable powder.
