How to Scald Breastmilk?

Updated on January 27, 2009
A.D. asks from Maricopa, AZ
7 answers

Hi mamas!

I have started to notice that my breastmilk sometimes smells sour out of the freezer. I read in my Medela info that it may be due to an increase/decrease in the enzyme Lipase. The Medela info suggests scalding my milk before freezing it...but doesn't say how to do that! I'm sure I can find info on the internet, but I'm not too good at searching so I thought I'd start here! Does anyone know how to do this? I'm assuming it has something to do with getting my milk super hot, but all the other info says never boil breastmilk! Also, I pump into the Medela storage bottles and then pour it into the Medela freezer bags. So do I scald in the bottle or the bag? Do I wait for it to cool before freezing? I have no idea how to do this!

Thanks for any info you can offer!

1 mom found this helpful

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So What Happened?

Thanks for the advice mamas! I was able to get info from my lactation consultant and she said the same thing as Roberta's advice. I tried it, so we'll see if it works! Also, someone posted about not being sure about whether Medela's products are all BPA free....they are. Everything Medela makes is BPA free and has been since before this whole BPA-Free craze. Thanks again!

More Answers



answers from Tucson on

Coppied from the Kellymom web site:

A few mothers find that their refrigerated or frozen milk begins to smell or taste soapy, sour, or even rancid soon after it's stored, even though all storage guidelines have been followed closely. Per Lawrence & Lawrence (p. 781), the speculation is that these mothers have an excess of the enzyme lipase in their milk, which begins to break down the milk fat soon after the milk is expressed. Most babies do not mind a mild change in taste, and the milk is not harmful, but the stronger the taste the more likely that baby will reject it.

Lipase is an enzyme that is normally present in human milk and has several known beneficial functions:

Lipases help keep milk fat well-mixed (emulsified) with the "whey" portion of the milk, and also keep the fat globules small so that they are easily digestible (Lawrence & Lawrence, p. 156).
Lipases also help to break down fats in the milk, so that fat soluble nutrients (vitamins A & D, for example) and free fatty acids (which help to protect baby from illness) are easily available to baby (Lawrence & Lawrence, p. 156).
The primary lipase in human milk, bile salt-stimulated lipase (BSSL), "has been found to be the major factor inactivating protozoans" (Lawrence & Lawrence, p. 203).
Per Lawrence & Lawrence (p. 158), the amount of BSSL in a particular mother's milk does not vary during a feed, and is not different at different times of day or different stages of lactation. There is evidence that there may be a decrease in lipase activity over time in mothers who are malnourished.

What can I do if my storage problem is due to excess lipase? Once the milk becomes sour or rancid smelling/tasting, there is no known way to salvage it. However, newly expressed milk can be stored by heating the milk to a scald to inactivate the lipase and stop the process of fat digestion. Scald the milk as soon after expression as possible.

To scald milk:

Heat milk to about 180 F (82 C), or until you see little bubbles around the edge of the pan (not to a full, rolling boil).
Quickly cool and store the milk.
Scalding the milk will destroy some of the antiinfective properties of the milk and may lower some nutrient levels, but this is not likely to be an issue unless all of the milk that baby is receiving has been heat-treated.

Per Lawrence & Lawrence, bile salt-stimulated lipase can also be destroyed by heating the milk at 144.5 F (62.5 C) for one minute (p. 205), or at 163 F (72 C) for up to 15 seconds (p. 771).

There is more info at the link above and you can search that site for even more articles.

Hope this helps! Also consider calling LaLecheLeague hotline or attending a meeting.


1 mom found this helpful


answers from Phoenix on

A. if it were me and i were using a certain company's product and were not quite sure what they mean for you to do then the only thing is for you to get in touch with them. They will have a customer service number or email address somewhere on the paperwork. They are the ones that produced the paperwork so go back to the horses mouth, so to speak, and get them to tell you exactly what you need to do and why.
Good luck.



answers from Phoenix on

I know you've already figured this question out, but I wanted to add that it doesnt' actually make the milk bad for the baby, it just makes it smell, so if your baby takes it fine you don't need to do the extra steps. My baby didn't care for it - but a lot of babies don't care at all. Good luck.



answers from Phoenix on

Dear A.
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Back To Me all The Time stress out Feel Lone and No One Understand Why am Trying to not Fall part when my 15 year old Talk back to me My Husband dose Not Care how up set am
So Keep in side and cry when Feel That no one Hear My Talk
Thanks C.



answers from Phoenix on

I would definitely not heat any food in plastic, even for a short time. We all get exposed to too much plastic residue from many sources...I'd scald milk first, then get it it even possible to use glass?? I hate plastic.
Medela is a good company and all but I am not sure if they have tested all their products for BPA and other chemical transfer under many conditions. I bet you could call them and ask though.



answers from Phoenix on

Hi A.,

I use to Breast Feed also and pump. I also had a Medela Breast Pump. I would suggest calling the Medela Corporation. This is not something you want to take a chance on. At that time in my life I did not deal with the internet so I always called and I know they have a 1-800# I believe. I was especially paranoid with my first (you know First Time Mom and w/Breast Feeding). Breast Milk is not something you want to take a chance on. I recommend calling so you go right to the source. You don't want to take any chances or have any uncertainties with something like the quality of your breast milk and how it might affect your baby. I personally have never heard of scalding your breast milk!! Sounds new.

God Bless You and Your Baby.




answers from Albuquerque on

I would call a lactation consultant. Your fee to her will be worth it. I would really try to avoid heating your breast milk. It seems scalding it would destroy many of the beneficial bacteria, enzymes, proteins and more.

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