Women's Health: Postpartum Community
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Avatar universal

frozen breast milk

I have noticed that when I pull a bottle out from the freezer of expressed breast milk, once it starts to thaw it has somewhat of a sour smell.  I put the milk in the freezer within 24 hours of when I pump it and it doesn't have an odor when I put it in.  I store it in either the Avent bottles or the Medela pumping bottles.  I worry about feeding it to my dd for fear it will make her sick, but I have no idea how it could go bad.  Does anybody notice the same thing?
11 Responses
192918 tn?1199454779
How long was it frozen for?  Could it be freezer burn??  I have only used the freezer bags and with those you can get all of the air out, so freezer burn isn't really an issue.  Also, how did you thaw it out?
Avatar universal
Well, my dd is only 9 weeks so the milk is probably a month old.  It had only been sitting out for about 10 minutes when I took the lid off and smelled it, so it was still frozen.  It doesn't smell like freezer burn.  It is very strange though.  I might try those bags and see if that makes a difference.
238474 tn?1192417309
I used the bags and didn't have any issues with funky smelling milk.  I would dump the milk, in any case, if I was you.
134578 tn?1546634665
I have heard that sometimes frozen breast milk changes its flavor and smell, to a more sour smell, but that it does not harm the breast milk nutritionally nor does it cause the milk to be unsafe for the baby to drink.  It has to do with the proteins in the milk and their reaction to being frozen, I think I recall.  You might google "freeze breast milk" and see what comes up.  I sure wouldn't throw it away.  Your pediatrician might also know about this.
127529 tn?1331844380
It is perfectly normal, nearly all my frozen breast milk smells like this, I think it is pretty disgusting but baby drinks it back all the same. It also varies from person to person as the proteins are different for each individual. Don't worry. Breastmilk can be stored in the seperate freezer part of your fridge for 3 months and up to 12 months in the deep freeze if your baby was a healthy full term baby, I still have over 15 litres frozen some dating back to February and it is perfectly fine.
175662 tn?1282217256
Chiro what bags are you using?  I'm wondering if it is related to storing in the bottles.  I've been bottle storing as well, I should perhaps consider getting the bags instead (I've been thinking of it just not sure which).
118074 tn?1228332603
Use the bag, I tried Gerber and Medela.  I threw out the ones that smelt sour...Smell it after you pump and if it smells normal then it shouldn't smell sour aftre it's been forzen.
127529 tn?1331844380
I have mine stored in bottles and bags (gerbera), makes no difference, as I said it is perfectly normal, I was told by the nurses on the NICU unit my first child was in that it is normal for it to smell slightly sour after freezing, freezing changes the structure of the proteins in the milk, you do not need to throw it away if it has been kept sealed in bags or bottles and has been kept at a constant temperature. It is also normal for the milk to look like it has bits in it, once warmed and given a little shake to mix this dissapears.
127529 tn?1331844380

I knew I had seen this information somewhere! It is the fats in the milk that change, thats why it can smell and appear different.
Avatar universal
I am finding the same thing, I've unthawed 3 bags of milk that are only between 2-4 weeks old and that were frozen within 24 hrs. I threw out the first two, b/c they smelled sour, kind of like when your baby throws up/spits up sfter a feeding. But, the more research I do, the more I find manu other people have the same thing. Changing the chemical makeup of the milk makes sense after freezing, so I hope everyone is right and my baby stays healthy. Thanks for all the write ins, very helpful.
Avatar universal
Also, I wanted to add, I did a test at home. I pumped fresh milk and put it in the fridge in a sealed bottle, it didn't smell when I put it in. I went back 24 hrs later and smelled it and it was starting to smell sour, just like the thawed milk. Not sure what this means, but I think it means the milk is ok.
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