The Right Way to Store Breast Milk

Now more and more breastfeeding mothers are active outside the home. Expressing breast milk is also an option so that the child's nutritional intake is still met. That's why it's important to know how to properly store expressed breast milk.


There are various choices of places to store expressed breast milk, such as glass bottles, plastic bottles with a label free of hazardous materials, or special plastic packaging for breast milk. It's best to avoid storing expressed breast milk in bottles or plastic packaging that is commonly used for general purposes. This is because the storage area for breast milk also affects the quality of the stored milk.

Keep Packaging Clean

In order to maintain the quality of stored breast milk, it is important to first sterilize baby bottles or containers for storing expressed breast milk that will be refrigerated or frozen. Sterilize by boiling the bottle and the part of the breast pump that comes into contact with the skin in boiling hot water for about 5-10 minutes.

In addition to manual boiling, you can also use an electric sterilizer. But before that, don't forget to check the safety and durability of the packaging on the label. Be careful when sterilizing bottles made of glass, because this material is more at risk of breaking.

It is no less important to prevent the development of bacteria from expressed breast milk, namely maintaining hand hygiene when expressing or when storing breast milk in packaging. Use soap to wash hands before expressing breast milk, and wash bottles of breast milk before sterilization.

For expressed breast milk that will be frozen, put the bottle directly into the freezer immediately after expressing. You should not fill the bottle or plastic packaging completely. The reason is that expressed breast milk tends to expand in a frozen state.

Especially for the plastic packaging that holds the expressed breast milk, place it again in a container or other packaging box before putting it in the refrigerator. This is because plastic packaging is more at risk of leakage. Finally, don't forget to put a label that includes the date the milk was expressed, on the bottle or plastic packaging.

Storage Time

The storage of expressed breast milk should be adjusted according to its use. Breast milk that will be used immediately is best placed in a part of the refrigerator that will not freeze.

Expressed breast milk can be stored from a few hours to several months, depending on the temperature at which it was placed. Here are the principles of breast milk storage that you should know:

  • Expressed breast milk lasts up to 6 hours if placed at room temperature around 25 degrees Celsius.
  • Expressed breast milk lasts up to 24 hours, when stored in a cooler with an ice pack. This method can be one solution to save ASIP when the power goes out.
  • Expressed breast milk lasts up to 5 days, when placed in the refrigerator section of the refrigerator with a minimum temperature of 4 degrees Celsius.
  • Expressed breast milk lasts up to 6 months if stored in the freezer at a temperature of -18 degrees Celsius or lower.
Just keep in mind, the process of freezing expressed breast milk may remove some substances that are important to ward off infection in infants. The longer the storage of expressed breast milk, either refrigerated or frozen, will eliminate the vitamin C content in breast milk. However, frozen breast milk still has a much better nutritional value than formula milk.

Tips for Defrosting Expressed Breast Milk

Thawed frozen breast milk is likely to experience changes in color, smell, and consistency compared to fresh breast milk. Therefore, it is natural for you to find breast milk settling after being stored in the refrigerator. This condition is normal and simply shake the storage bottle to mix it again.

Some babies refuse frozen expressed breast milk. If so, you can try shortening the shelf life of breast milk or warming breast milk before giving it to your baby.

  • To thaw frozen breast milk, you can use an electric breast milk warmer that can be used at home or in the car. If not available, then you can place a bottle of expressed breast milk in a pot or bowl of warm water. Wait a few moments. Remember, do not put the pot or basin on the stove that is on.
  • Frozen breast milk should not be removed immediately at room temperature. Several studies reveal that rapid changes in temperature can affect the antibody content in breast milk that is beneficial for babies. Frozen expressed breast milk from the freezer can be placed first in the freezer in the refrigerator, then warmed as above.
  • If expressed breast milk is needed urgently, then you can place it under running water at normal temperature. Then continue to drain it with warm water. If it's not warm enough, place the bottle in a bowl of warm water. To check if the temperature of breast milk is right for your little one, put a drop on the wrist. If the temperature is right, breast milk can be directly given to the little one.
  • Although it seems easy, avoid reheating or defrosting. Express breast milk using the microwave. This tool can create spots on expressed breast milk bottles that may be harmful to your little one. These spots appear due to hot temperatures. Again, changing milk too quickly in expressed breast milk can eliminate the antibody content needed by the baby.
    Breast milk is the best nutritional intake for babies. Proper storage of expressed breast milk can help breastfeeding mothers who work or do activities outside the home to meet the needs of their babies. If necessary, consult a doctor for more information.