Spoiled Breastmilk

Updated on October 26, 2009
P.O. asks from Antioch, TN
10 answers

How can you tell if and when breastmilk is spoiled or no longer good.

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answers from Orlando on

Just like regular milk it will smell spoiled. I never had my frozen BM spoil, but did have some go bad in a cooler while I was out one time. It definitely smelled bad, like spoiled milk.

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answers from Miami on

Pat I have some experience in this department. With my third child, I had my heart set on breastfeeding him like I did with my first two daughters. I breastfed exclusively with my first two but with my third child, he was not gaining weight due to a weak suck. By the time I consulted a lactation specialist, my milk had decreased so much that I had to supplement with formula but I was pumping to help my milk supply increase.

Long story short, my milk never increased enough to sustain my son so he eventually weaned BUT with the milk I had managed to pump, which wasn't much, I froze it so that I could combine it with formula. What I discovered was truly devastating. When I defrosted a bag of frozen breast milk, I found that it smelled funny. I tasted it and the taste was so putrid that I threw it away. I then opened another bag of frozen milk only to find that ALL of my frozen milk was the same way. I immediately called my lactation consultant and this is what I learned. Every woman has an enzyme in her breast milk. This enzyme is called Lipase and it's not harmful at all to the baby. However, when too much Lipase is present, once the milk is chilled or frozen, the Lipase in the milk causes the breast milk to "spoil" and the longer the milk is frozen, the stronger the smell and taste becomes. Now, the consultant reassured me that the milk was not bad to give to my baby but with something that tasted so badly, I could NOT give it to my baby.

There are guidelines for storing the breast milk to ensure that it does not spoil.
Fresh expressed breast milk can be stored in the refrigerator for 8 days. Personally, I would not wait 8 days before using, but again, these are guidelines. Always chill your breast milk in the refrigerator before putting it into the freezer. You don't want to put warm milk directly into the freezer. Always date your expressed/pumped milk and use the oldest milk first. Thaw frozen breast milk in warm water. Do not use a microwave oven, as it destroys the antibodies in the milk. Frozen breast milk can be defrosted in the refrigerator but MUST be used within 24 hours. Frozen expressed milk can be stored in the back of the freezer (the coldest part) of a regular freezer for 3-6 months and in a deep freeze for 6 months. If milk is curdled, even if it doesn't smell, it's probably spoiled. If a baby hasn't finished a bottle of expressed milk, you can use it within the next 24 hours, but toss it if it's any longer than that. I hope this helps. I'm sure you'll get plenty of info from other moms.

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answers from Miami on

has ALL the answers!

also you could call la leche league for free w/ your questions: The La Leche League Breastfeeding Helpline w/access to toll free breastfeeding help 24 hours a day. Just call 1-877-4-LALECHE (1-877-452-5324)

1 mom found this helpful


answers from Miami on

My midwife said that it is good for 8 hours at room temperature and a year in the freezer. I'm forgetting the time in the refrigerator but I think she said a week. You will need to check on that one, sorry.



answers from Orlando on

you will definitely know, it stinks! I stuck with the 5/5/5 rule, 5 hrs room temp, 5 days in the fridge and 5 months in the freeze. You can probably give or take from that, I read it somewhere and it was easy for me to remember. I only had one episode of sour milk, I must have put the wrong date on it and went a day or so too long in the fridge. It looked a little funny even before opening it, and then when I did, whew! there was no mistake it was sour! I think it instantly goes bad, unlike pasteurized cow's milk, where you have to keep sniffing and even taste to see if it's ok. Just follow good storage tips, and you'll be fine. Congrats on BF your baby!



answers from Jacksonville on

smell it!! make sure u know how your breastmilk smells when u pump..once is spoiled is smells pretty disgusting!! You will know right away is spoiled...breastmilk in the refrigerator changes in color and even gets an oily coat like is spoiled..but i always go by smell..Good luck!!

PS: Mother of 3..currently breastfeeding third child..10 years of experience..:)



answers from Miami on

Everyone gave you good info. Just wanted to add that spoiled milk actually smells bad! If you take a whiff of your milk before giving it to your baby, you won't give her/him spoiled milk by mistake! ;)



answers from Miami on

Hi, Pat. You can tell spoiled breastmilk the same way you would tell if cow's milk was spoiled. #1, if it smells rotten, and #2, it will also probably not be so liquidy (it will probably get chunky the way cow's milk does), and it will also probably not be the same color as it was when it was fresh.

You should always store milk that you have gotten by breastpump in the refrigerator, just as you would for cow's milk or formula. Make sure it doesn't sit out in hot weather for very long.

Don't worry about milk fresh from the breast. It's impossible for your breast milk to go bad while it's still inside your breasts.




answers from Tampa on

Storage guidelines
Temperature Storage Time
Freshly expressed milk
Warm room 79°F / 25°C 4-6 hours
Room temperature 66-72°F / 19-22°C 10 hours
Insulated cooler / icepacks 60°F / 15°C 24 hours
Refrigerated Milk (Store at back, away from door)
Refrigerator (fresh milk) 32-39°F / 0-4°C 8 days
Refrigerator (thawed milk) 32-39°F / 0-4°C 24 hours
Frozen Milk (Do not refreeze! Store at back, away from door/sides)
Freezer compartment
inside refrigerator (older-style) Varies 2 weeks
Self-contained freezer unit
of a refrigerator/freezer Varies 3-6 months
Separate deep freeze 0°F / 19°C 6-12 months
These guidelines are for milk expressed for a full-term healthy baby.
If baby is seriously ill and/or hospitalized, discuss storage guidelines with baby’s doctor.

To avoid waste and for easier thawing & warming, store milk in 1-4 ounce portions. Date milk before storing. Milk from different pumping sessions/days may be combined in one container – use the date of the first milk expressed.

Breastmilk is not spoiled unless it smells really bad or tastes sour.

To thaw milk

Thaw slowly in the refrigerator (this takes about 12 hours – try putting it in the fridge the night before you need it). Avoid letting milk sit out at room temperature to thaw.
For quicker thawing, hold container under running water - start cool and gradually increase temperature.
Previously frozen milk may be kept in the refrigerator for up to 24 hours after it has finished thawing. Do not refreeze.

To warm milk

Heat water in a cup or other small container, then place frozen milk in the water to warm; or
Use a bottle warmer.
NEVER microwave human milk or heat it directly on the stove.
The cream will rise to the top of the milk during storage. Gently swirl milk (do not shake) to mix before checking temperature and offering to baby.

If baby does not finish milk at one feeding, it may be refrigerated and offered at the next feeding before it is discarded.



answers from Tampa on

I have a Medela magnet with all that information, whether the milk is fresh, refrigerated, or frozen. Too much for me type. Go to their website and I am sure it will give you all that info.