How to Store, Warm & Cook with Breast Milk

How you store and warm excess breast milk is important.  A few easy methods for storing and re-heating excess breast/human milk will ensure safe preservation and feeding.

The most important thing to keep in mind when storing breast milk is avoiding cross-contamination with other foods—all containers for collection and storage of breast milk should be kept clean. When possible, pump directly into storage containers.

It is acceptable to store breast/human milk for up to 4 days in the refrigerator (preferably the back of the refrigerator to prevent intermittent warming from the door opening). If you plan to freeze breast/human milk, try to freeze within 24 hours as the beneficial enzymes begin to change at approximately 25 hours. This doesn’t have to be a determining factor in how quickly expressed milk is frozen but consider storing as soon as possible. If not used within 96 hours (4 days), fresh breast/human milk should be transferred to the freezer in a clean, freezer-safe container and dated.

It is acceptable to store breast/human milk in a freezer with an attached refrigerator (0°F or −18°C) for up to 6 months and in a deep freezer (−4°F or −20°C) for up to 9-12 months; however, the sooner it is used, the better. Frozen breast/human milk safely lasts in the freezer for 1 month while preserving most of the nutrients; after 3 months in the freezer, there is a noteworthy decline in concentrations of fats, calories and other macronutrients.

Additionally, research suggests that nutrition in breast/human milk varies based on mother’s and a suckling baby’s changing needs—another phenomenon of nature supported by the immune-boosting elements and probiotic bacteria of breast/human milk. In short, fresh breastmilk is the most beneficial, but when storage is necessary, use the most recent breast/human milk first rather than older milk stored in the freezer. Have a surplus? Consider donating excess milk.

In summary:

Correction to: ABM Clinical Protocol #8: Human Milk Storage Information for Home Use for Full-Term Infants, Revised 2017, by Eglash A, Simon L, and The Academy of Breastfeeding Medicine Breastfeed Med 2017;12(7):390-395. DOI: 10.1089/dna.2017.29047.aje. (2018). Breastfeeding medicine : the official journal of the Academy of Breastfeeding Medicine, 13(6), 459. https://doi.org/10.1089/bfm.2017.29047.aje.correx

I’ve heard it’s safe to add freshly expressed breast/human milk to a container of refrigerated breast/human milk. Is that true?

To date, one study has demonstrated that adding freshly expressed breast/human milk to refrigerated breast/human milk is safe. However, no official AAP guidelines or otherwise have been modified. It’s prudent to await more studies documenting this practice as safe before we see updated guidelines.

How to properly thaw frozen breast milk

To thaw frozen breast milk, plan ahead and defrost overnight in the refrigerator, and never on the counter. And because heating to excessive temperatures can greatly alter the nutrient quality, refrain from defrosting breast milk in the microwave or on the stove. Once breast milk is completely thawed, you have 24 hours to use it. And remember: breast milk does not have to be heated at all! Many babies will happily drink room temperature—or even cold—breast milk.

Can you cook with breast milk?

We know adding fresh breast milk to your baby’s food is beneficial. But what about cooking with breast milk? Does heat destroy the exquisite properties that Mother Nature intends for us to deliver to our babies?

Upon a close look, heat does change the structure, quality, and nutrient density of breast milk. But before we write off cooking with breast milk, let’s look more closely. Scientific research provides insight, but often doesn’t always apply in the real world.

Some studies have suggested that when breast milk is heated to just 100.4°F (38°C)—slightly above body temperature—its proteins begin to break down. This means that even when we heat stored breast milk it can lose important immunologically “active” and digestive components that benefit babies. For example, enzyme activity (amylase, which breaks down carbohydrates and lipase, which breaks down fats) begins to decrease at 104 degrees F (40 C). These enzymes are important because they help infants with immature digestion to break down nutrients the milk itself, so that nutrients can be absorbed and utilized for growth.

So do you lose nutrients in the cooking process? Yes. That said, breast milk still offers amazing nutritional value, so if you have excess milk, you should absolutely feel good about incorporating it into other foods. Just know it would be better just to add some fresh breast milk stirred into food after it has been cooked. Read on for our suggestions for using excess milk!

Tips for using breast milk in solid food

If you are able to produce excess breast milk there are a number of ways it can be incorporated into your baby’s food. We know, however, that heating breast milk can alter the nutritional profile. When possible, look for ways to incorporate fresh breast milk into your baby’s foods. Additional ideas:

Fresh breast milk (still quite nutrient-dense):

Thawed breast milk (fewer nutrients):

Frozen breast milk (especially older milk that you don’t want to waste):

Recipe: Breast Milk Hibiscus Smoothie (12 mos+)

Blend ingredients and serve.

Reviewed by:

Jamie Truppi, MSN, CNS for Solid Starts

Rachel Ruiz, MD for Solid Starts

Source: Bransburg-Zabary, S., Virozub, A., & Mimouni, F. B. (2015). Human Milk Warming Temperatures Using a Simulation of Currently Available Storage and Warming Methods. PloS one, 10(6), e0128806