Choosing the right storage system is the first step to safely storing your expressed breastmilk for your child’s future feedings. Bottles tend to be the best option for storing milk in the refrigerator since you can pump, store and feed from the same container. Breastmilk storage bags are typically the first choice for freezer storage since they allow you to store more milk in the freezer by maximizing your freezer storage space since each bag takes up less space than a bottle.