if you pump, why can't you shake the milk?

Starfish21 · July 2009

I see a reference to this on kellymom, but the link is broken. Why can't you shake a bottle of expressed breast milk to get the cream to reincorporate? Why is it bad or what happens?

EJS425 · July 2009

?? I always shook mine!! hmm.. never heard otherwise before..

I guess its too late for me to worry about it now.. I stopped ep'ing when L was 6 weeks!

jamie.renee · July 2009

With my first two girls I exclusively pumped. I don't remember why but you are suppose to swirl it, not shake. It can break down or something like that if you shake it up.

BennyL · July 2009

Thanks for posting this! I found the fulltext of the Kelly Mom reference online:

Don't Shake the Milk

Linda J. Smith, BSE, FACCE, IBCLC

Why not?

Because shaking expressed mothers' milk (or boiling or freezing it) denatures the shaped molecules of the protective proteins, leaving only the pieces - the amino acids - the parts. Lactoferrin, lysozyme, and other protective components work their protection magic when they are in their original shaped molecular structure. Some components remain intact, even during freezing, shaking or heating. They not only protect the gut from many kinds of infection, but also prevent inflammation of the gut lining. Even broken up, the separate amino acids are still really good stuff and are digested by the baby as nutrients.

Imagine a set of pop-beads assembled into a necklace or bracelet. When the beads are acting as a bracelet or necklace, they are doing their job as protective elements. When you break apart the beads, you have in your hand many individual chunks of amino acids which are then digested.

Cellular components are also susceptible to damage by physical stress. After all, they are living cells.

With mother's milk, you get at least two functions for the price of one. With manufactured formula, you only get the individual beads, never the necklace or bracelet. And never the living cells.

So, please handle human milk gently, respectfully and kindly. It's far more than perfect food for babies - it's a living tissue and protective shield too.

sullys_grl · July 2009

I shake it but gently...

IMHO I have an issue with the whole "don't shake it" idea. I took oodles of Microbiology classes in college, and you can only really denature (break apart) proteins by heating them up (beyond what you would heat a bottle...think egg whites) or REALLY shaking them (think blender) OR a combo of both.

I think as long as you just shake it sorta gently to reincorporate it it's okay. I mean, they homogenize cow milk (which is basically what we are trying to do by shaking it) much more forcefully and it doesn't mess with those proteins...so as long as you aren't boiling your breast milk and then throwing it in a martini shaker you should be okay!

Sorry to geek out on you!! Geeked

mandarod · July 2009

i've also found that when you warm the bottle (we just put the bottle in a cup of warm water), the cream pretty much reincorporates itself. then i just swirl it to make sure.