I have seen a couple of companies that specialize in freeze-drying breast milk (e.g. Milkify). Their websites tout studies saying that this process is safe and has minimal effect on nutritional content and antioxidants (though they acknowledge that not all antibodies are retained). I’d be interested in your thoughts on whether this is a safe practice!
—Desperate to Save My Freezer Stash
I have been so curious about this, especially since it was definitely not around when I had my kids. I had to resort to the regular old chest freezer, which now lingers forlorn in our basement.
The idea of freeze-drying breast milk, rather than simply freezing it, is to make storage easier and to preserve the milk for longer. This is especially important and, indeed, was first developed in service of milk banks. Human milk banks provide donor milk for (e.g.) babies in the NICU who need it and whose mothers cannot produce milk on their own. Storing this milk in freezers is onerous and may be more challenging in resource-poor environments (as in the developing world). A freeze-dry technology would allow milk to be stored longer and doesn’t require the cold temperatures.
Obviously, a primary concern is whether the nutrient mix in breast milk is deteriorated by the freeze-drying process. The good news is that it doesn’t seem to be. This isn’t a complicated thing to test — you take milk, measure the nutrients, freeze-dry it, and measure again. Looking at various milk components (proteins, fats, etc.), the freeze-drying process does not seem to affect them (e.g. here, here, here). As you note, there may be a slight deterioration of antibodies, which can happen with freezing in general.
This makes the technology very promising for the milk-bank use case.
Unsurprisingly, companies have also endeavored to offer it to individuals. Milkify is one example (I will note: the research discussion on its website is top-notch). The use case is slightly more complicated than for milk banks (i.e. you do not typically need to store your milk for three years). But I can see places where I, personally, would have used this service. Travel. Saving space in your house.
The primary downside is the not-inconsiderable cost. But safety-wise, it looks good.
Final note: Let’s say you do use the traditional freezer method. And let’s say that someone leaves the freezer open and things defrost. Please read this post about how refreezing is fine, before you panic and kill the person who left the door ajar.
