milorad kravic/E+/Getty Images

5 Signs Your Breast Milk Has Gone Bad

There's nothing worse than spending so much time pumping your breast milk only to find out that it's gone bad sooner than you expected. The stuff is called liquid gold for a reason, and no mom wants to have to throw out even a drop of her hard-won milk. Luckily, getting to know a few of the signs your breast milk has gone bad will save you from the pain of having to pump your milk and dump it a few days later.

Not unlike cow's milk, breast milk will spoil if left out in the open, or even in the refrigerator for longer than it should be. According to La Leche League International, breast milk should be left at room temperature for no longer than four to six hours. Similarly, they stated that it should be refrigerated for no more than eight days (absolute maximum, the ideal amount is 72 hours.) After that point, the milk should be frozen, or used immediately, as long as none of the signs of spoilage are present.

Once you learn these signs that your milk has gone bad, you'll no longer have to play a guessing game with your precious liquid gold.


It Will Smell Foul

According to Modern Mom, spoiled breast milk has a similar smell to spoiled cow's milk. If you notice a definite foul odor from the milk, it's spoiled. However, many moms report a metallic or soapy smell from their milk, but according to Breastfeeding Today (a publication by La Leche League International), this smell is simply caused by higher levels of the enzyme lipase that some mothers produce. There is nothing harmful in a soapy smell, and most babies drink the milk without issue.


It Doesn't Mix When Swirled

Although breast milk often separates into fatty and non-fatty layers when stored, if the milk is still fresh it should re-congeal with a gentle swirl. If your breast milk doesn't mix when swirled, or if there are chunks in the milk that won't mix, according to Modern Mom, it's spoiled.


It Sat In The Fridge For Longer Than 3 Days

According to Baby Center, expressed breast milk will stay fresh in the refrigerator for three to five days, depending on the temperature and location you store the milk. For maximum shelf life, store your milk in the "heart" of your fridge and not in the door, where the temperature fluctuates the most.


It Wasn't Sealed Properly

Like anything, if your breast milk wasn't sealed properly or the bag or container had a tear in it, the chances of your milk spoiling greatly increase. The Mayo Clinic recommended storing your milk in hard plastic containers, or in bags specifically designed for breast milk, since these are least likely to break or let contaminants in.


It Tastes Sour

Obviously, the easiest way to tell if your milk is sour is to taste a bit of it yourself. Modern Mom noted that spoiled breast milk will taste similar to spoiled cow's milk, so if you taste something off, it's probably best not to feed it to your baby.