Information about expressing and storing milk
Unfortunately, there is no clear answer to this question as there is no research about whether it is safe or not. Until recently, the standard answer was to discard any breastmilk left in the bottle after a feed. However, recently it has been suggested that it might be okay to store breastmilk in the fridge for a short time. The current thinking is that bacteria growth is possible, but not likely, because fresh breastmilk has anti-bacterial properties, and a breastfed baby has a strong immune system to deal with any bacteria that do grow.
You can thaw your frozen breastmilk by holding it under cool running water. Gradually increase the water temperature to heat it to a comfortable feeding temperature. This is a temperature that feels warm, not hot, on your wrist. Periodically mix the milk in the bag or bottle by swirling gently, as it defrosts. Milk can also be thawed in a refrigerator overnight. Do not thaw or heat your milk in a microwave or directly on the stove.
Yes. Expressed human milk can be kept in a common refrigerator at the workplace or at a daycare centre. Check that the refrigerator temperature is 4C (39F) or less. Both the US Centers for Disease Control and the US Occupational Safety and Health Administration agree that human milk is not among the body fluids that require special handling or storage in a separate refrigerator.
Colostrum is the 'first milk' produced by your breasts, starting during pregnancy. It is a concentrated form of "mature milk", which is very high in protein, antibodies and other protective components that are important for your newborn. It is thicker than mature milk and often has a yellowish colour to it. It is produced in small amounts (10-100 mL/24 hours), which is perfect for your newborn's tiny tummy. The smaller volumes also give your baby a chance to learn to nurse without being overwhelmed by a large flow of milk in the first few days.