Any pumping mom will tell you that spilling breast milk is basically like spilling liquid gold. But going to feed your baby some of your pumped breast milk and realizing it's spoiled? Well, there are no words. It's thinking you had an extra hundred dollars in the bank, but nope, you spent it all at Target and you don't even like what you bought. It's a horrible situation, especially when it's time to pour it down the drain, and you may find yourself wondering how to use breast milk that's gone bad.
Like any kind of milk, breast milk can spoil and smell and taste sour or rancid. And just like any other type of spoiled dairy, you have to toss it. There are plenty of things you can do with extra breast milk, like donating it or using it to treat your baby's diaper rash. But there's nothing you can do with spoiled breast milk or breast milk that has been stored longer than the storage guidelines.
If you're unsure if your breast milk is bad or not, take another look (and smell and taste). KellyMom notes that soapy-smelling breast milk doesn't mean it has soured, it could just mean that your breast milk has excess lipase in it. By scalding the milk, you may be able to save it, but it's too late if the milk has reached the sour or rancid stage.
The Mayo Clinic also notes that thawed milk might have a different odor than fresh breast milk, but as long as it doesn't smell spoiled, it's OK to feed your baby. If your baby refuses it, try shortening your storage time, or mix it in with freshly expressed milk to make the taste a little better. But, like in all food-related queries, when in doubt, throw it out. I know it sucks, but nobody wants spoiled breast milk, not even a hungry baby.