Freeze-dried breast milk has been studied for decades.
Freeze-drying human milk isn't a new idea. Researchers have been studying it since the 1950s, looking at nutrients, fats, immune components, antibacterial activity and how the powder holds up in storage. Here's what they found, where the evidence is still limited, and what we've tested ourselves.
From the first paper to a 48-publication review
- 1 1955 First published research Scientists describe freeze-drying as a way to preserve human milk.
- 2 2015 Antibacterial activity 125 milk samples show the natural bacteria-fighting activity holds up.
- 3 2016 Nutrients compared Milk from 116 mothers is tested before and after freeze-drying.
- 4 2020 Proteins mapped 245 milk proteins are compared before and after drying.
- 5 2024 48 publications reviewed A scoping review brings the evidence together in one place.
Not one number. Five areas of evidence.
Breast milk is complex, so good research looks at more than one thing. A 2024 scoping review identified 48 publications on freeze-dried human milk. Here's what that research covers, in plain language.
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01
Macronutrients
Generally retainedRead the study ↗What they measureProtein, fat, carbohydrates and overall composition, before and after freeze-drying.
What studies foundProtein, glucose and fats are generally well conserved. In a study of milk from 116 mothers, every nutrient measured was kept after freeze-drying and 6 months of storage.
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02
Fats and fatty acids
Mostly stableRead the study ↗What they measureThe fatty-acid profile, DHA, and signs that fats are breaking down (oxidation).
What studies foundThe overall fatty-acid profile stayed stable over 3 to 6 months of storage, with no signs of oxidation. DHA and arachidonic acid were lower than in the original milk, and fat globules get smaller.
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03
Immune components
Some reductionRead the review ↗What they measureAntibodies (IgA, IgG, IgM), lactoferrin, lysozyme and other bioactive proteins.
What studies foundThe overall protein profile looks broadly unchanged, but the 2024 review reports that some immunoglobulins and enzymes are reduced. How much is kept depends on the process.
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04
Antibacterial activity
Retained in studiesRead the study ↗What they measureMilk's natural ability to kill or slow the growth of bacteria.
What studies foundIn 125 samples from 65 donors, bactericidal activity was not significantly changed by freeze-drying compared with freezing.
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05
Storage stability
Depends on storageRead the study ↗What they measureHow time, temperature, moisture, air and packaging affect the powder once it's dry.
What studies foundFatty acids stayed stable over 3 months of storage, while vitamin C declined, and antioxidant capacity fell when the powder was kept warm. Cool, dry and sealed storage matters.
Preservation is not sterilisation.
Freeze-drying removes water, which helps stop microbes from growing while the powder stays dry. It doesn't kill bacteria or viruses already in the milk, and researchers are clear that freeze-drying alone should not be treated as a microbial safety step.
So safety depends on the whole process.
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It starts with how milk is handledFreeze-drying can't undo contamination, so every bag is checked, logged and photographed when it arrives. -
One mama, one machineProcessed in our ISO-6 cleanroom, with equipment cleaned before, between and after every batch. -
Dried to a very low water activityEvery batch must read well below the 0.6 food safety benchmark. -
Sealed in an ISO-5 cabinetPacked under laminar flow into vacuum-sealed sachets that keep out air and moisture.
We test our own process, not just the category.
Published research tells us what freeze-drying can do in general. We've also tested milk processed with our own equipment, methods and packaging.
Nutrient retention
We compared key macronutrients before and after freeze-drying, with up to 97% retained.
Microbial safety
Milk processed through our system has been laboratory tested for microbial safety.
Tested shelf life
Shelf-life testing supports up to three years for unopened sachets stored as instructed.
Results apply to the samples, process, packaging and test conditions evaluated. "Up to 97%" refers to the macronutrients measured, not every nutrient or bioactive component in breast milk. Full technical reports are kept by Wonderbewbz and can be shared confidentially with clinical, regulatory and research partners.
Read the studies for yourself.
A short, curated list of peer-reviewed studies and reviews, each with a plain-language summary. Tap a topic to narrow it down.
9 publications shown
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2024Scoping reviewRead publication
Lyophilized (freeze-dried) human milk for preterm infants: a scoping review
Brings together 48 publications on freeze-dried human milk. It reports smaller fat globules and lower levels of some enzymes, vitamin C and immunoglobulins, and calls for more research in premature babies.
Sproat et al., Journal of Perinatology -
2021Safety and bioactivityRead publication
Combination of high-pressure processing and freeze-drying as the most effective techniques in maintaining biological values and microbiological safety of donor milk
Compared ways to preserve donor milk. Freeze-drying alone was not treated as a microbial safety step, but it worked well for long-term storage once milk had been made safe another way.
Jarzynka et al., International Journal of Environmental Research and Public Health -
2020ProteinsRead publication
The freeze-drying does not influence the proteomic profiles of human milk
Mapped 245 proteins in milk before and after freeze-drying and found no significant difference. It was a small study (9 samples from 3 mothers), so it's a useful signal rather than the final word.
Hahn et al., Journal of Maternal-Fetal & Neonatal Medicine -
2018Fatty acidsRead publication
Human milk enriched with human milk lyophilisate for feeding very low birth weight preterm infants: a preclinical experimental study focusing on fatty acid profile
Looked at fats in freeze-dried milk from 50 donors. The overall fat profile didn't change over 3 and 6 months of storage and showed no oxidation, although DHA and arachidonic acid were lower than in the original milk.
Bomfim et al., PLoS ONE -
2017AntibodiesRead publication
Impact of pasteurization/freeze-drying on available immunoglobulin content of the mature human milk
Measured protein and antibodies (IgA, IgG, IgM) in milk that was pasteurised, then freeze-dried, as some hospital milk banks do. How much was kept depended on the pasteurisation temperature used first.
Castro Albarrán et al., Nutrición Hospitalaria (in Spanish) -
2016NutrientsRead publication
The effect of freeze-drying on the nutrient, polyphenol, and oxidant levels of breast milk
Tested milk from 116 mothers. Protein, glucose, fats, polyphenols and oxidation markers were all conserved after freeze-drying and 6 months of storage at 4°C.
Cortez et al., Breastfeeding Medicine -
2015Antibacterial activityRead publication
Human milk bactericidal properties: effect of lyophilization and relation to maternal factors and milk components
Checked 125 samples from 65 donors. Milk's natural ability to kill bacteria was not significantly changed by freeze-drying compared with freezing.
Salcedo et al., Journal of Pediatric Gastroenterology and Nutrition -
2014StorageRead publication
Vitamins, fatty acids, and antioxidant capacity stability during storage of freeze-dried human milk
Stored freeze-dried milk for 3 months at 4°C and 40°C. Fatty acids and some forms of vitamin E stayed stable, but vitamin C dropped at both temperatures and antioxidant capacity fell in the warmer one.
Lozano et al., International Journal of Food Sciences and Nutrition -
1955Early researchRead publication
Preservation of human milk by freeze-drying
One of the earliest published papers on freeze-drying human milk, showing researchers have been exploring the idea for about 70 years.
Köttgen, Deutsche Medizinische Wochenschrift (in German)
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This page is for education and is not medical advice.
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