Why does my freshly pumped breast milk smell sour?

Understanding the Sour Smell of Freshly Pumped Breast Milk
For many mothers, the experience of pumping breast milk is often accompanied by a range of sensory observations, including the smell of the milk. While most mothers describe breast milk as having a sweet or neutral scent, some may notice a sour odor that raises concerns. Understanding the reasons behind this phenomenon can help alleviate worries and ensure that both mother and baby are healthy.
The Role of Lipase
One of the primary culprits behind the sour smell in freshly pumped breast milk is lipase, an enzyme naturally present in human milk. Lipase plays a crucial role in breaking down milk fats, making them easier for infants to digest. However, in some cases, particularly when milk is stored, excess lipase can lead to a noticeable change in odor. Mothers have reported that their milk can smell soapy, sour, or even reminiscent of parmesan cheese due to this enzyme’s activity.
When breast milk is refrigerated or frozen, the lipase can continue to break down fats, which may result in a stronger sour smell over time. This is particularly true if the milk is stored for an extended period. The longer the milk is kept, the more pronounced the sour odor can become.
Distinguishing Between Normal and Spoiled Milk
It’s important to differentiate between milk that has a sour smell due to lipase activity and milk that has genuinely spoiled. Freshly pumped breast milk that smells sour but does not taste rancid is typically safe for consumption. In contrast, milk that has truly soured will have a distinct odor and taste similar to spoiled cow’s milk. If the milk smells off and has a rancid taste, it may indicate spoilage due to bacterial growth, which can occur if the milk was not stored properly.
What Can Mothers Do?
For mothers who are concerned about the sour smell of their breast milk, there are a few strategies to consider. One option is to scald the milk before storing it. This process involves heating the milk to a temperature that inactivates lipase, thereby preventing it from altering the milk’s smell and taste over time. However, this method may also reduce some of the beneficial properties of breast milk, so it’s essential to weigh the pros and cons.
Additionally, mothers can experiment with different storage methods. Using glass containers instead of plastic, or ensuring that the milk is cooled quickly after pumping, can help maintain its freshness.
Conclusion
In summary, a sour smell in freshly pumped breast milk is often linked to the presence of lipase, an enzyme that aids in fat digestion. While this can be concerning for mothers, it is usually not a sign of spoilage. By understanding the factors that contribute to this odor and taking appropriate measures, mothers can feel more confident in the quality of their breast milk and its suitability for their babies.

What happens if my baby drinks sour breast milk?

If your baby has had spoiled breast milk, they’ll likely let you know. They may throw up, or have an upset stomach, diarrhea or fever. It’s important to call your pediatrician if you think your baby may be sick from having spoiled breast milk.

Why does my newborn smell like sour milk?

Milk or formula residue
Between milk dribbling out the side of your baby’s mouth during feeds and spit-ups that occur frequently after you feed your baby, it shouldn’t come as a surprise that you might get a whiff of some sour milk smell occasionally.

How do I stop my breast milk from being sour?

Once the milk becomes sour or rancid smelling/tasting, there is no known way to salvage it. However, newly expressed milk can be stored by heating the milk to a scald to inactivate the lipase and stop the process of fat digestion. Scald the milk as soon after expression as possible.

Can breast milk get sour in the breast?

Results: The transition from colostrum to mature milk was accompanied by changes in the taste of the milk, such as decreased saltiness and umami and increased bitterness and sourness. Umami and saltiness increased in milk from inflamed breasts.

How do you neutralize sour milk smell?

Baking soda
For years, one of the simplest, least expensive, and most adaptable methods for used to remove milk smell has been baking soda.

What causes breast milk to be sour?

The true cause of the sour smell and taste isn’t necessarily the amount of lipase in your milk, but the rate of lipase activity. While some moms can store milk in the refrigerator or freezer for a while with no change in smell, others notice a change after just 24 hours.

How to know if breastmilk is spoiled?

It will also smell bad, much like spoiled cow’s milk. And, like spoiled cow’s milk, breast milk that’s old will taste sour. (It’s fine to taste your breast milk to check!) Always label your pumped milk with a time and date so you can tell how old it is.

Why does my breast milk smell sour right after pumping?

Your milk may have excess lipase in it, which can cause stored breastmilk to smell sour or soapy. Lipase is a beneficial enzyme found in breast milk that helps break down milk fat. If your breastmilk has excess lipase, the longer the milk is stored, the stronger the smell becomes.

Why does my new milk smell sour?

Smell: If milk has a bad smell, it may indicate spoilage. Fresh milk should have a mild, pleasant aroma. A sour or off smell usually means that bacteria have started to grow, and it’s best not to consume it.

Why does my breast smell sour?

While sweat itself doesn’t smell, you may develop body odor when there is the presence of bacteria on your skin. This is particularly why sweaty breasts smell sour or musky. Body odor comes from bacteria on the skin, which breaks down sweat produced by the apocrine glands.