How to Know If Frozen Breast Milk Has Gone Bad

New moms know you can't put a price on having enough breast milk for your baby. Saving surplus breast milk can help you build up a milk supply for daycare or other times when mom and baby are apart and can prevent the need to supplement with formula. Frozen breast milk can last for more than six weeks in the freezer.

1. Mark each container of breast milk with the date it was frozen so you can manage your inventory. Check the dates on the container when you remove it from the freezer -- breast milk frozen in a freezer compartment inside a fridge is good for up to two weeks. Breast milk stored in a conventional refrigerator with an attached -- but separate -- freezer can last three to four months. Breast milk stored in a deep freezer can last more than six months.

1. Use the oldest breast milk first. Your breast milk is naturally formulated for your baby's current developmental needs, so it should be used as close to her current developmental stage as possible.

1. Thaw your breast milk in the refrigerator for 12 hours. You may also thaw it under cool to warm running water to expedite the process. Never microwave it and avoid bringing it to a boil. Swirl -- don't shake -- the milk, to mix the cream back in.

1. Smell the milk. Just like spoiled cow's milk, spoiled breast milk smells sour and should be tossed. Smell is a better indicator than appearance, as breast milk can look lumpy or clumpy. It is normal for breast milk to separate, and the look of normal breast milk can change depending on your baby's age or what you eat.

1. Scald your breast milk before freezing it, if you find your frozen breast milk smells soapy and you know it should be good. Breast milk high in lipase causes the fat to break down and results in a soapy smell and your baby may refuse the milk. Scalding the breast milk before freezing it deactivates the lipase.