Many mothers are aware that breast milk gives their babies a head start for healthy growth and development. Breastfeeding mothers who work outside the home often pump their milk using breast pumps. The milk is then stored in sanitary bottles or other containers and fed to the infant as needed. While breast milk does not spoil as easily as many people suspect, it is important to know the signs that could indicate that your breast milk has gone bad. Spoiled milk could make your child sick, so you must avoid serving it if you suspect this may be the case.
Smell the milk. Spoiled breast milk has an unmistakable foul odor that is similar to spoiled cow's milk. If you detect this odor, the milk must be thrown away.
Observe the appearance of the breast milk. Breast milk that has separated into two layers is still fine to use and can simply be shaken prior to serving. This separation occurs when the fatty portion of the milk rises to the top. If, however, the milk has formed clumps of solid material, it may have spoiled and should be thrown away.
Taste the milk. It is not uncommon for breast milk to have a metallic or soapy taste, which is created as a result of the milk's enzymes breaking it down. If, however, the milk has a definite sour taste, it may have spoiled and should not be served to your child.