My wife pumps and puts the milk in the fridge if it's not time for a feeding. We have to supplement with formula because the baby drinks about 4 more ounces a day than she makes. Feeding from the breast never worked out.
Anyway, the problem is, sometimes, we get the breast milk out and heat it up (running hot water over it or just holding it in warm hands) and the milk looks curdled. We just throw it out and grab a different bottle of breast milk whenever that happens out fear that it has gone bad.
Why does that happen? Is the milk still safe? It's never in the fridge for more than a day or so and we make sure to rotate them and even have some contraption where the new milk goes in one side and the oldest milk comes from the other side.