Only pack as much milk as you need. Improperly thawing your milk can make it spoil or lose more of its nutrients. Regardless of what type of storage container you choose, make sure that you label and date the milk so that you use it before it goes bad. What type of bottles should I use to store breast milk? Breast Milking - Paying the Cost to be the Boss 2: Japanese Breast Milk You can repeat the power pumping as often as you need to.