Expressed breastmilk can be stored at room temperature, refrigerated or frozen. 1. Room temperature storage: Expressed breastmilk can be stored for 2~4 hours at room temperature of 15℃, 1~2 hours at room temperature of 19℃~22℃, and only 1 hour at room temperature of 25℃. 2. Refrigerated storage: in 0 ℃ ~ 4 ℃ refrigerator freezer, expressed breastmilk can generally be stored for 2 ~ 4 days. 3. Freezing: In the deep freezer, usually below -18℃, breastmilk can be stored for a long time, usually up to 6 months or more. Breastmilk should not be frozen or refrigerated too much at a time. Breastmilk stored in the refrigerator or freezer needs to be thawed before feeding, and can be heated to the right temperature with warm water, avoiding microwave heating.