How do I know if my expressed milk is bad already?

Determining if breast milk has gone bad, "If breast milk has been stored longer than the guidelines recommend, it should be thrown out. Remember that all breast milk is not going to look the same, as it varies in color. If fat in the breast milk separates during storage, shake the container and the fat will mix with the milk. Breast milk can sometimes taste or smell soapy; fat can also break down during storage, causing this smell. Note that it is still safe to consume when this happens. Spoiled milk will smell sour and should not be consumed." From: http://www.livestrong.com/article/507375-how-do-i-know-if-my-stored-breast-milk-is-bad/

Like what everyone says, smelling and tasting the milk is the best way to determine if the milk has gone bad. If it smell/taste sour, it is best to throw it out. Here are some useful Do's and Don'ts when it comes to storing milk: http://www.mayoclinic.org/healthy-lifestyle/infant-and-toddler-health/in-depth/breast-milk-storage/art-20046350

In general, don't offer expressed milk that has exceeded the storage time to your baby. Smelling the milk is the best way to test if it is rancid or not. Ensure that your expressed milk is properly stored so that it can keep fresh for longer. http://www.wikihow.com/Know-when-Expressed-Breast-Milk-Is-Spoiled

If it tastes sour. Tastes your breastmilk before offering to your baby. It's normal if breastmilk smells fishy. However it should not taste sour.

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