Breastmilk Storage Guide
If for whatever reason your baby needs expressed breast milk (EBM) as part of their feeding routine, here is my guide to storing and transporting EBM. Breastmilk is fresh, living food with many antioxidants, antibacterial, prebiotic, probiotic, and immune-boosting properties in addition to macro and micronutrients. It is best to chill or refrigerate expressed breastmilk (EBM) as soon as possible if it will not be used during that time.
Storing & Freezing EBM
- EBM should be stored in the back of the fridge or freezer to prevent intermittent rewarming due to door opening.
- EBM should be kept away from the walls of self-defrosting freezers.
- Space should be left at the top of the container to allow for expansion with freezing.
- EBM should be labelled with the date and name of the child if the milk will be used in a health or child-care setting.
- Storing EBM in a variety of small increments such as 15–60 mL will reduce the waste of thawed EBM.
- All containers with EBM should be well sealed to prevent contamination.
- Freshly expressed warm milk should not be added to already cooled or frozen milk. It is best to cool down the new EBM first before adding it to older stored milk.
Transporting EBM
One study has shown that transporting EBM alongside an ice pack in a small cooler (equivalent to 15C) is safe for up to 24 hours.
Storing & Freezing Effects On EBM
The bactericidal (natural bacteria-killing substances found in breastmilk) capacity of stored refrigerated human milk declines significantly by 48–72 hours. Lipid composition and lipase activity remained stable for up to 96 hours in the refrigerator. Lactoferrin levels are stable in the refrigerator for 4–5 days. Immune factors generally won’t diminish for 48 hours.
Fat, protein, and calories decline in human milk when frozen for 90 days compared to freshly expressed breastmilk. Frozen human milk has a significant increase in acidity by three months, likely due to ongoing lipase activity, which increases free fatty acids in the milk.
At the end of the day, fresh is best and then EBM correctly stored in the fridge or freezer is the next best option. And for those babies who will be needing to be stored and frozen EBM, knowing how to do it safely and why is so important.
This knowledge has been adapted by JWP into an easy-to-read guide from the Academy of Breastfeeding Medicine: Human milk storage protocol.