Does Breastmilk Really Never Expire? Here’s What You Need to Know

January 27, 2025

There's nothing worse than throwing out your breastmilk when it's gone bad... except, throwing out breastmilk when it's still perfectly good! If you were told that breastmilk "expires" or "goes bad" after 6-12 months... read on.

Let's start this off with an experiment. Go to your freezer and grab a bag of frozen veggies - let's say, peas. Turn it around and you'll see the "best before" date is probably within 3 years of purchase.

Breastmilk is the perfect nutrition for your babe, packed with antibodies, enzymes, and hormones that support growth and development. For mamas who pump and store breastmilk, questions about safety and longevity are top of mind. A common concern is whether breastmilk expires in the freezer... spoiler alert - it does not.

Breastmilk Storage Guidelines

According to the FDA, USDA, Centers for Disease Control and Prevention (CDC) and other sources like the Library of Congress, frozen breastmilk is safe indefinitely as long as it remains frozen at a consistent temperature. You know how much I love research, so I've included direct links to these sources at the bottom of the page.

So what's the deal with the 6-12 months guideline? These guidelines are for best quality, NOT because it’s unsafe to use. Think about it, the 3-year-old peas you just took out of your freezer are safe, nutritious and recommended as one of the first foods for your babe, but the freshly expressed superfood you’ve just made a few months ago and stored in the freezer is dead? I think not.

This distinction is crucial: while breastmilk may lose some of its nutritional value over time, it does not become unsafe to consume if stored correctly.

The truth of the matter is, that breastmilk research is not a money maker - continuing to breastfeed your babe after 12 months doesn't benefit big corp or big pharma, so there's not much interest in researching older breastmilk - but it does profound things for the health and development of your babe, and improves YOUR health as the breastfeeding mama. Continuing to give breastmilk past 12 months whether that be direct, bottle or added to foods improves IQ, and reduces the risk of serious diseases long term. Not to mention the cost savings over time of lowered healthcare costs, lost work and childcare because of your babe’s improved health status.

Here’s what the CDC advises:

Breastmilk stored in a deep freezer (-4°F/-20°C) can maintain optimal quality for up to 12 months or longer.

If you scroll down on the CDC's website on Breastmilk Storage, you'll see references to the USDA's food safety. This is the "fine print" where you'll see the heavy research on frozen food safety. Again, because there is more research on 3-year-old frozen peas (a big business money maker) than 12-month-old frozen breastmilk.

Over time, the fat in breastmilk starts to oxidize (like a browning avocado or apple in the fridge). This is what's affecting the taste and if you have high lipase, it’s the breakdown of fat that’s making the breastmilk smell a little different. But like an avocado or apple that’s browned in the fridge, it’s still safe to eat. When looking at the CDC guidelines, they specifically talk about the differences in breastmilk storage guidelines in their FAQs section. But how often does one venture to the FAQs section of the CDC website?

"Why do I see different breast milk storage recommendations?

Many factors can affect how long and where breast milk can be stored. These factors include storage temperature, rising and falling of the temperature, and cleanliness while expressing and handling breast milk. Therefore, it is difficult to recommend exact times for storing breast milk in various locations."

-CDC's FAQs Section

Freezing and Food Safety: USDA Research

The USDA’s guidelines on frozen food safety provide a solid foundation for understanding why breastmilk remains safe over time. According to the USDA:

"Food stored constantly at 0° will always be safe. Only the quality suffers with lengthy freezer storage."
Freezing protects food by slowing the movement of molecules and causing microbes to enter a sleep stage. This halts the growth of microorganisms that cause both food spoilage and foodborne illness.

This means that as long as your breastmilk remains frozen at a constant 0° or lower, it is safe for your baby to consume, regardless of how long it has been stored.

Nutritional Quality Over Time

While frozen breastmilk remains safe indefinitely, it’s important to note that prolonged storage may impact its nutritional content. For instance:

Some of the beneficial enzymes and antibodies may degrade slightly over time.
Fat separation might occur, which can make your breastmilk appear grainy or speckled, but does not affect its safety. Gently swirling the milk or letting it warm longer in a bottle warmer can help the fat blend back in.

Even breastmilk that has been frozen for a year or more still provides excellent nutrition and is superior to formula. If you’re concerned about nutrient loss, use older milk for mixing with solid foods or in smaller amounts alongside freshly expressed milk.

Can I Feed a New Baby Older Breastmilk?

Most of the guidelines you see are to protect the vulnerable, new babies who require the highest form of nutrition - they apply less to your 15-month-old who takes turns putting the dog toy in their mouth. Now, this isn't to say that you should feed a new baby breastmilk that's 2 years old regularly (but there isn't actual research on 2-year-old frozen breastmilk, so guidelines are there to err on the side of caution). For new babies, yes it's best to feed breastmilk that is under 12 months for optimal nutrition - but if you're in a pinch, have a dip in supply or circumstances don't allow for breastmilk available for your babe (emergency scenarios) then using older milk is still safe - just not as nutritious as more freshly expressed.

Freezer Burn and Breastmilk

Freezer burn is another concern many mamas have when storing breastmilk for extended periods. The USDA explains that freezer burn does not make food unsafe; it merely affects the taste and texture. Freezer burn occurs when air comes into contact with the surface of the food, causing a dry, rough area to appear on your frozen breastmilk. Freezer burn does not compromise the safety of breastmilk.

To prevent freezer burn, ensure that breastmilk storage bags are sealed tightly, and remove as much air as possible before freezing. Proper sealing minimizes air exposure and helps maintain the milk’s quality over time.

High Lipase and Breastmilk

Some mamas notice that their breastmilk develops a soapy or metallic smell after being frozen for long periods, which is often attributed to high lipase activity. Lipase is an enzyme naturally present in all breastmilk that helps babies digest fats. While high lipase activity can change the taste or smell of breastmilk, it does not make the milk unsafe for your baby. There is no evidence that breastmilk affected by high lipase is harmful to babies, and most babies will still accept it without issue.

If your baby shows more preference for “fresh from the tap” milk vs. thawed milk, you can try mixing fresh milk with previously frozen milk to gradually introduce it. Another option is scalding milk before freezing to deactivate lipase, though this process may reduce some of the milk’s beneficial properties. Many experts, including the Academy of Breastfeeding Medicine, advise against scalding unless absolutely necessary, as it can destroy important enzymes and immunological factors.

This is where freeze-drying your breastmilk comes in to save the day!

Freeze-Drying Breastmilk: The Reassuring Option

For mamas seeking even longer-term storage solutions, freeze-drying breastmilk offers an innovative option. According to a study published in the Journal of Food Composition and Analysis, freeze-drying preserves the nutrient composition of breastmilk and maintains its microbiological safety even after 12 months of storage at room temperature. This process involves freezing the milk and then removing the water content through sublimation, creating a shelf-stable product that doesn’t require refrigeration.

Benefits of Freeze-Drying Your Breastmilk Include:

Nutritional Retention:

The study found no significant changes in the levels of fats, proteins, or carbohydrates during the freeze-drying process or after storage.

Extended Shelf Life:

Freeze-dried breastmilk can be stored without refrigeration, making it an ideal option for emergencies or travel. No more panicking about lost breastmilk when your freezer fails - because it’s a shelf-stable powder sitting on your pantry shelf now!

Convenience:

Reconstituting freeze-dried milk with warm water restores it to its original state, allowing mamas to provide their babies with all the benefits of breastmilk without the need for freezer space.

No more worrying about thawing, melting or losing nutrients 12 months later!

Now Back to Those Guidelines...

Just because the research says properly stored frozen breastmilk will not harm your baby - every mother's comfort level will be different. The fresher your breastmilk, the most nutritious of course, but even 18-month-old breastmilk will still give your babe life-long health benefits.

#Momlife can be scary and when you want the best for your babe, it’s easy to overthink things or take advice for face value - especially for breastmilk storage guidelines when they seem so concrete. But when you dig deeper, you find out what the research says and tend to look at the “guidelines” as… a guide - not an expiration schedule. Hopefully, this helped save your stash from being thrown away and you can keep giving the original superfood to your babe for as long as possible!

Remember:

You don’t need to toss milk that has been frozen for over 12 months unless it shows signs of spoilage after thawing.
Your effort in pumping and freezing provides your baby with invaluable nutrition, no matter how long it’s been stored.

Now, imagine finding a stash of breastmilk in your freezer from eight months ago, you know... behind the bag of peas. Instead of worrying about its safety, you can feel confident knowing it’s still perfectly good. Whether you’re using it for bottles, blending it into your toddler’s smoothies, or sending it to Booby Food for freeze-drying that milk is still liquid gold.