How to Preserve Breast Milk, Dehydrate or Freeze Dry ?

Reptiles don’t feed their young—once offspring hatch they are on their own.  The egg-laying Avians (birds) do feed their young, but it is a complex process where usually both parents hunt food and deliver it to the nest.

Mammals, on the other hand, have it “made in the shade”.  As long as “Mom” is eating, she has a ready supply of the single most nutritious substance available for mammal babies: breast milk.

Often called Liquid Gold for Babies, human breast milk (HBM) contains water, carbohydrates, proteins, and fat.  That’s all good and essential stuff, but it also contains enzymes, antibodies, stem cells, immune factors, white cells, vitamins, minerals, growth factors, and hormones.

These additional components cannot all be added to formula.  Baby formula is a good substitute or addition, but will never be as complete as natural breast milk.

So what do you do if Mom is a CEO, building cleaner, doctor, police officer, or teacher, and Dad is the stay-at-home architect, author, or computer programmer?  Mom is away and baby needs to eat every two hours…

Preserving Liquid Gold

There are three choices for preserving breast milk: refrigerated, frozen, or dried.

• Refrigerated will last eight days if the fridge is a stable 4℃ (39℉) or less, and three days if you’re uncertain of the temperature;
• Frozen at -18℃ (-0℉) will hold for nine months, and at -20℃ (-4℉) will be good for one full year;
• Dried HBM varies depending of your choice of storage method. HBM prepared in a dehydrator can last for several months. Freeze-dried HBM can endure for three years or more.

Using Frozen HBM

This is easy enough to do.  If it is frozen in single use portions, simply place it in lukewarm (not hot!) water until it is in a liquid state again, swirl to assure any separated fat is homogenized and serve! 

If it is in larger portions, put the container in a larger container in the sink and let room temperature water trickle over it until it returns to a liquid state.  Rotate the container top-to-bottom a few times to get any separated fat back into a homogeneous mixture, and refrigerate.  If you’re not in a rush, let it defrost in the refrigerator overnight—and you don’t have to watch over it this way.

Dehydrating Human Breast Milk

Pouring it on the trays, in an even layer, and letting the machine run for several hours is the typically recommended methodology on YouTube™. The technique for dehydrating HBM is actually very specific.  Your run of the mill dehydrator will not have sufficient sensitivity to hold the correct temperature so that vital components of HBM are not damaged or destroyed.  At 60℃ (140℉) irreversible damage occurs.  As a dehydrator cycles on and off to maintain the dehydrating temperature for HBM of 49℃ - 54℃ (120℉-130℉), it can go beyond that setting, even after the heater shuts off.

Using a dehydrator requires a high quality unit that is specifically designed for human breast milk, or a precision model, by a high-end manufacturer, in order to do the job properly.  You’re not drying parsley or making jerky that is relatively insensitive to temperature variations; HBM is valuable stuff!

More importantly, it is often recommended that dehydrated HBM powder is stored in a sterile glass container with a tight fitting lid in a cool place, away from light.  This can last for three months, but you should be aware that each time you open the container you’re exposing it to the possibility of environmental contamination.  If the bottle is particularly cold, atmospheric moisture can quickly condense inside the bottle and make the powder vulnerable to faster deterioration.

Freeze Drying Human Breast Milk

Here is where Freeze Drying comes to the rescue of human breast milk!  HBM that has been frozen can be dehydrated, turned into powder, and all the while preserving all the good factors that make it so valuable, without damage.

Stored in individual, high barrier Mylar™ bags, protected from oxygen and moisture, as well as UV light, or simply from contamination in the environment, your shelf stable HBM can last for three years.  In fact, HBM donor banks have been doing this since the 1950s.  Those vital antibodies and nutrients are preserved and ready to go almost instantly. 

You can add body temperature water for infants less than six months; room temperature is suitable after that; and with premade, even straight out of the refrigerator, when they’re ready for it…  The sheer convenience is great!

Freeze Drying HBM is simplicity itself, as opposed to sending it out to a commercial outfit and paying $1.25 per ounce (or more) for conversion.  Do it yourself at home with your own freeze dryer.

First, collect your milk and freeze it, preferably in flat bags of even and reasonably shallow thickness.  Try for something about the width of your little finger held sideways to make the process relatively quick.

Next, sterilize your freeze dryer trays to keep the milk as uncontaminated as possible.  Some people like to use easily sterilized silicone mats, which lend themselves to this task.  You can get all of the milk off the trays when it’s complete.

Set up your freeze dryer as usual (pre-cool, etc.) and once all the milk is out of the original freezing bags and on the trays, slide it all in.  Set the machine to run from 24 -36 hours as required, and get on with your life.

Once complete, slide the lyophilized milk into a nice big (fresh, sterile) Ziploc bag and use a hand roller to turn the big flakey chunks into powder.  Portion it out into your Mylar™ bags, add an oxygen absorber, remove as much air as possible (nice if you have a vacuum sealer!) and close each bag up.

To revitalize it, simply take about 15 ml (one tablespoon) of powder and two ounces of warm water, and swirl it for a while to make sure the elements have mixed.  Leave it for a while to give everything the chance it needs to reabsorb its natural amount of water, swirl it again, and serve!

The Takeaway

While the contents of these bags are still good for 10 years, the nutritional value starts to decay after about 3-4 years, so although usable, less useful after the nominal storage time.  It can still be sprinkled onto the baby’s food in its dry form, or made into smoothies, soup, or whatever strikes your fancy.

And, of course, if a neighbor has a full term, non-immunocompromised, healthy baby, and the Mom is in short supply, you can always help out with a donation, if you happen to be very productive yourself!  What a way to be a good neighbor!

Learn more about freeze dryers and freeze drying here.