Freezing is the current standard for storage of breast milk. However, long-term freezing of breast milk results in a decrease in quality of the milk. Some important and significant decreases in quality have been observed in human milk stored in the freezer.

At Milkify, we believe in evidence-based scientific research.

Researchers around the world now agree that freeze-drying breast milk is safe and more effective than freezing for preserving the nutritional, immunological, and probiotic properties of breast milk that make it the gold standard of nutrition. We put together this guide to explain the differences between freezing and freeze-drying, and what the current research says about both.


​Human milk is the ideal food to nourish infants - it contains vital macronutrients (proteins, carbohydrates, & fats) that are needed for healthy development​.

FROZEN: Freezer storage has been shown in several recent studies to cause a significant decline in the fat and caloric content of breast milk. In addition, protein content of breast milk may be modified by the freeze-thaw cycle.

FREEZE-DRIED: Proteins, fats, and carbohydrates (including human milk oligosaccharides) were found to be protected by freeze-drying.


Antioxidants in breast milk help prevent damage to important cellular components caused by reactive oxygen species. Vitamins and minerals are micronutrients that are also important for development and functioning of various organ systems.

FROZEN: Frozen breast milk was shown to have significantly decreased antioxidant activity. 

FREEZE-DRIED: Freeze-drying had no significant effect on antioxidant capacity.


Breast milk contains a complex mix of immune factors that help provide protection from infectious agents. Antibodies, cytokines, growth factors, and other bioactive factors in breast milk are important forms of protection while the infant's own immune system is maturing.

FROZEN: Antibodies such as IgA, IgM, and IgG, and other bioactive immune factors (such as IL-8, TGF-β, and IL-10) degrade over time in the freezer, and concentrations in breast milk are significantly reduced after extended freezer storage.

FREEZE-DRIED: Freeze-drying resulted in retention of 75% of IgA antibodies, and 80% of IgG and IgM antibodies


Human breast milk is a living food! Probiotic bacteria in your breast milk (such as Lactobacillus and Bifidobacterium) are important for establishing your infant's initial gut microbiota. Human milk oligosaccharides (HMOs) are important prebiotics for these bacteria, as they provide the food that these bacteria use to grow and multiply.

FROZEN: Many probiotic bacterial species do not survive extended freezer storage, and even one freeze/thaw significantly decreases their viability.

FREEZE-DRIED: Freeze-drying is a common method of preservation for probiotics, and is used routinely in research and industrial applications.