Why Your Breast Milk Smells Like Vinegar (Explained)

Why does breast milk smell like vinegar? Could it be a fact? Or is our psychology playing pranks with us? Questions like this usually question any woman who just discovered that her breast milk smells sour would ask.

Biologically, only nursing mothers should produce breast milk, and every nursing mother deals with breast milk daily.

And during such dealing, you might have noticed that your breast milk smells like vinegar, so why does my breast milk smell like vinegar?

Sometimes the smell becomes more pronounced when the pumped breast milk is left for some hours, and you may become jittery that it smells awful.

This article will answer your questions on breast milk smelling like vinegar and other questions you might be dealing with concerning breast milk.

Breast Milk: Everything You Need To Know

Breast milk is the fluid produced by the mammary gland in female vertebrates.

It is produced by the mammary glands, stored in the breast, and flows through the nipples, especially when sensitized by a baby’s mouth or by gentle touch.

The breast’s possession helps differentiate between the male and the female mammal in the vertebrate phylum. Breast development is one of the characteristic signs in female humans during puberty.

Pregnant women undergo some noticeable physical changes in their body, which could be hormonal. They include signs like swelling of the feet, enlargement of the uterus causing the bulging of the stomach, and formation of breast milk through the help of the hormone oxytocin.

The hormone prolactin is in charge of the flow of breast milk and sometimes needs to be stimulated by the sucking activity of the baby on the mother’s nipple, which helps trigger breast milk flow.

Most mothers’ especially first-time moms, get scared and worried when they experience a low milk supply or if their breast milk isn’t flowing well.

This is usually a source of concern because of how big the breast milk laden in the breast is and how it causes general discomfort.

Read Also: How To Deal With No Breast Milk After Delivery

Breast Milk Smells Like Vinegar: Here’s Why

grainy breast milk

Wondering what causes the smell of vinegar, you perceive from your breast milk? The answer is due to the excessive production of the enzyme Lipase.

Enzymes are biological catalysts that speed up the rate of metabolic reactions in the human system. These enzymes are specific; they have a specified substrate or substance they act on.

The enzyme lipase is one of the human system’s biological catalysts that aids digestion.

It also aids in the breakdown of lipids or fats and oil to the end products fatty acids, and in the case of your baby who still feeds on breast milk, Lipase breaks down the breast milk fats so the baby can easily digest them.

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If you notice that your breast smells or tastes sour or feels soapy, do understand that it could result from excessive Lipase production that causes it, so they shouldn’t be jittery.

Breast milk contains excessive Lipase doesn’t make it unsafe for consumption; it can be consumed.

Some babies who are extremely sensitive to taste and smell may reject it because of the smell, while some wouldn’t even mind. So if your baby is comfortable drinking it, there is no course for alarm.

Read Also: Why Your Thawed Breast Milk Looks Grainy

What You Can Do To Prevent And Fix Excessive Lipase Production in Breast Milk

If you notice that your baby refuses to drink your breast milk due to the smell or taste due to the excessive production of Lipase, then there are ways that you can use to prevent or fix the Lipase reaction in your breast milk.

1. Test before freezing

When you are about to freeze your pumped breast milk, especially when the quantity is high, before freezing, taste the breast to see if there is any change in taste due to the action of Lipase, observe the milk for the color change, and then see if there is a change in smell.

After doing this, collect and freeze1-2 bags or small containers of breast milk for at least five days, assess the odor and then see if your baby will drink it.

2. Eliminate lipase-induced milk changes during freezing 

If test freezing proves that your breast milk was influenced by Lipase causing a change in smell or taste, and you’ve tried it on your baby, and you discovered that your baby is rejecting it, you should scald your fresh milk before freezing is carried out.

Scalding must be carried out before freezing; if not, the effects of the Lipase won’t be reversed.

  • To scald fresh milk: Put your breast milk in a pot and then apply heat to the breast milk; allow it to heat until tiny bubbles form around the edges of the pan (approximately 180° F). Ensure that boiling doesn’t take place. After scalding, remove the milk from the stove and allow it to cool before freezing.

Scalding is quite effective because it will prevent the enzymes from breaking down breast milk, but it comes with its disadvantage as it affects the amount of the beneficial component of the milk.

Read Also: What Happens If Baby Drinks Spoiled Breast Milk

What Are The Other Things That Can Change the Taste or Smell of Milk

Many factors can influence the smell and taste of breast milk apart from the enzyme lipase in the breast milk, and they are

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1. Food and Medications

Research has proven that sometimes what one eats influences breast milk, and milk can start the flavor based on the meal.

Breastfed babies tend to savor flavors and a greater variety of food when they begin taking solid food, unlike formula-based babies that may be selective with food.

Also, certain medications can affect the way breast milk smells and tastes.

2. Storage Techniques

Storage techniques have a way of influencing the smell, taste, and appearance of milk.

When you store milk either by standing at room temperature or in the refrigerator, you will notice separation into layers, with the creamy part staying on top. When it’s time to use the milk, swirl the container gently to mix the milk.

To avoid changes in the taste and smell of the milk, make sure that the storage aligns with the standard and current storage guidelines.

3. Freezing Habits

Freezing and thawing your breast milk also affect the taste and smell of the breast. Sometimes after defrosting milk, some women notice that the smell of their milk becomes unpleasant, and sometimes the taste is affected too.

4. Stress and Anxiety

Research has shown that postpartum anxiety can affect breast milk production. Stress and anxiety tend to increase the adrenaline level in the mother’s body, which hinders the natural milk ejection reflex.

This situation is usually common in first-time moms as they are often overwhelmed by breastfeeding and other baby-related issues.

5. Smoking

Smoking can also reduce the volume of your milk, as it stops the release of prolactin and oxytocin hormones in the body. Prolactin is needed for the optimal growth of breast and milk production.

Research on rats found that nicotine or tobacco fumes can reduce prolactin release and reduce milk supply. Nicotine fume was also found to hinder a baby’s growth and development.

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We hope this article has given in-depth knowledge to answer the question of breast milk smells like vinegar.

As mentioned earlier, we believe it could be as a result of the excessive production of the enzyme lipase in your breast milk which aids in the digestion of breast milk fats.

It could also be as a result of the food or medication ingested, or as a result of the storage techniques and freezing, habits used when dealing with excess milk.