53: Don’t Throw Out That Milk! Listen first…
Like most mothers, I stashed away any extra milk so that down the road, it would be available for my son (you know, for convenience or catastrophe- whatever may come). So imagine my horror (and hurt feelings) when I thawed some milk only to find it…utterly rejected. I smelled it and it had an “off” smell which led me immediately down a path of trying to figure out how an entire stash of frozen milk had gone bad… Turns out, it hadn’t gone bad. But, my milk probably had high lipase.
Lipase is a naturally occurring enzyme in everyone’s breast milk. It’s thought to help your baby digest and absorb nutrients from your milk. But, when you refrigerate or freeze human milk, the odor can change and it’s thought to be due to a higher amount of lipase. It’s sometimes described as soapy, mildly fishy, or even metallic smelling. The idea here is that the lipase breaks down triglycerides, which releases fatty acids, and the odor is thought to come from oxidation of those fatty acids.
Now according to the Academy of Breastfeeding Medicine, there’s actually no evidence that this causes infants to reject the milk. In fact, many infants are not bothered at all. And if they are happily taking your properly stored milk without complaint, then you don’t need to do a thing. There isn’t anything wrong with high lipase milk.
However, it is still commonly thought that a change in odor to stored breast milk, due to the impacts of lipase, is a turn off to some babies.
So what to do…
Well, one common strategy is to scold or heat the milk to deactivate the lipase before storing it in the freezer. This is an interesting strategy, because it’s a common recommendation, but really cumbersome to be scolding all of your freshly pumped milk (as if you really need an additional step to do). Also the Academy of Breastfeeding Medicine does not recommend heating your breastmilk to over 104 degrees fahrenheit (40 degrees celsius for those not in the U.S.) because it may also destroy active immunological properties that are a huge benefit to your baby drinking your milk.
Now my personal opinion here is that for a newborn taking formula, you are supposed to use boiled water, mix it, and then of course cool it before giving it to your baby, so heated breast milk versus heated formula- my guess is that even scalded breast milk is still really great.
But…good news! There are other less cumbersome options to deal with high lipase milk. Which I will be sharing with you next. But before I do, I just want to give you a little tip for if you do still choose to scald your breast milk before you store it in the freezer. The Ceres Chill- which is a multi use container for pumping moms, does make scalding breast milk easier. Because you can pump directly into it, and then put the inner chamber of milk to bob in the hot water to heat to the desired temperature. I did an entire interview with, Lisa Myers, the inventor of of the Ceres Chill and I am so impressed at her product because of all the other things it can do and her efforts toward quality and safety in her products so if you want to learn more check out Episode 39: The New Way to Store Pumped Milk on the Go. I am not an affiliate, by the way.
Okay so back to the funky smelling but perfectly good breast milk and what to do. I reached out to Ashley Daub, a pediatric registered dietician, to get to the bottom of the best way to safely address this issue.
Ashley says that first and foremost, if your baby has no qualms taking your higher lipase milk then there is no issue. Nothing to do or worry about. Feed away.
If your baby refuses it, then there are few strategies you can try that are safe for your baby and least impact the delicate and complex content of the milk.
The first and preferred option is to try to deep freeze freshly pumped milk as soon as possible. She says this is a good option because it better addresses the lipase, but still maintains the micronutrients and other important properties found in human milk. One study cited by the ABM, showed that freezing human milk to -112F, led to less change in the small compared to a conventional freezer at -2.2F. (That’s a difference of -80C versus -19C). The challenge for some is you not only need an effective deep freezer, but you need to freeze it as cold as it can go right away which is not always realistic.
For those who do not own a deep freezer (or if, like me, you would have had to chuck the crib to make space for it 😂) you can try adding 1-2 drops of alcohol free vanilla extract (that part is really important, alcohol free vanilla extract) to the bottle. When she told me about this option, I immediately asked her, “Is that safe?” to which she reminded me this is a common ingredient in baby formulas.
A third option is to prepare bottles with a half and half ratio of previously scaled and not scalded milk. That way you can preserve some of those micronutrients and antibodies and see if your baby will accept a less lipased out version.
Ashley says that at the end of the day, trial and error is the only way to know which of these options works for you and your baby. And she cautions parents against making up recipes and adding ingredients that are not proven safe for your baby.
Here are a few bonus tips to remember:
Always store breast milk in the back of the freezer and not near the opening to prevent partial warming.
Remember to cool your freshly pumped milk, which is warm, before adding it to any previously cold or frozen milk.
And, always use fresh milk first whenever you can since it has the most intact composition of all those benefits for your baby.
A special thank you to Ashley Daub, MS, RD, LDN, for contributing to this episode as we support mothers dealing with this tricky scenario.
If you haven’t already please rate the show (I’d prefer 5 stars but always encourage an honest rating). If you would like a downloadable and printable handout of proper handling and storage of breastmilk, which is always nice to have on the fridge so you don’t have to google it frequently, I have one linked in the description.
And until next week, I wish you easy feedings and good sleep stretches.
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