Human milk is a fresh, living substance—not just a ready-to-use food. When you make the effort to provide expressed milk for your baby, you are ensuring that your baby continues to receive ideal nourishment and protection against many diseases. Human milk’s anti-bacterial properties actually help it stay fresh. The live cells and antibodies in the milk that discourage the growth of bad bacteria in your baby’s intestines also guard against bacterial growth when the milk is stored in a container. The interpretation of research on human milk storage varies widely which is why when you ask 10 different people about storage guidelines - What are safe methods and temperatures for storing and defrosting and warming, you may get 5 different responses. Let's not get too hung up on the storage temperature information yet.