Storing Breast milk?

I have been pumping and freezing BM in medela bags for the past month or so in anticipation of returning to work. Last night I i defrosted a few bags to prepare thme for the baby sitter and they had a funny odor, kind of like a penny had been soaking in it. After going through 5 bags i started freaking out that the 40 bags of 4-6 ounces that i have stored have gone bad. After googling a bit I came across a few articles about too much Lipase in breast milk which can alter the taste and smell but it's still safe to give to the baby. Has this happened to anyone? I called my OB and was directed to a lacation consultant but she has not called me back yet.

Re: Storing Breast milk?

does the milk smell when in the bag - if yes then it could be some left on the outside - that happened to me - i would rinse each bag before putting it in a bottle

also some people's milk goes bad faster than others - and some people's milk does not freeze well -

Re: Storing Breast milk?

I had a lipase issue with my first baby and lost over 300 oz of frozen BM because of it. Even though the milk had a metallic odor/taste it was still fine- just a matter of the baby's taste preference. Instead of freezing, I had to keep 7 days worth of milk in the fridge and rotate it quicker than keeping it in the freezer.

The only good news is that if you have another baby, the lipase issue might not happen again. With my second baby, everything froze fine and no lipase issue!