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Symptoms of Baby Drinking Spoiled Breast Milk—3 Signs To Look For

symptoms of baby drinking spoiled breast milk

If you take a drink of spoiled milk that you purchased at the store, there is no confusing the fact that it’s gone bad. 

However, when you’re talking about expressed breast milk, it’s a far less exact science. Frozen breast milk that has thawed tastes different from mother to mother, and it’s more difficult to tell if the breast milk is now spoiled.

If you store breast milk, there’s a chance that it can go bad. Whether it’s forgetting to adhere to milk storage guidelines, not properly marking dates so that frozen breast milk has surpassed its date or some other issue, you have to be able to look for symptoms when you give baby spoiled milk.

Symptoms of baby drinking breast milk that is spoiled

If your baby drinks spoiled breast milk, you may wonder if you’ll be able to tell. 

Pumped breast milk that has been brought to room temperature or thawed breast milk that has been frozen may not taste exactly the same as when it was freshly expressed.

Changes in a mother’s diet can also alter how breast milk tastes.

You may wonder if you can be sure that you fed your baby spoiled breast milk or if they don’t like the fact that you had curry the night you pumped, and now the breast milk tastes different.

This article will help you understand how to tell if your baby has fed on breast milk that has gone sour.

It is important to note that feeding your baby drinks spoilt breast milk can lead to food poising, upset stomach, cramps, diarrhea and vomiting.

How to tell when baby drinks spoiled breast milk

How to know if breast milk is bad

There are specific ways to tell if expressed breast milk has gone bad or is spoiled breast milk. The following are some of the best indicators that human milk has soured.

1. Sour smell

When you are storing breast milk, small changes can occur in the milk that causes it to have a strange smell. 

For example, women with high lipase breast milk end up with milk that smells fishy, metallic, or soapy.

While this may seem odd, this milk is still OK to feed your baby. Scalding the milk can eliminate that smell if it seems to bother your little one, but there is nothing wrong with the breast milk. 

However, when you have spoiled breast milk, the smell of rancid fats or a sour smell is relatively tricky to confuse with anything else. Dumping this milk is for the best, as it’s not healthy for your baby to consume spoiled breast milk.

2. How it looks

It is usual for milk to separate when you store breast milk properly. Stored breast milk may have a fat separation so that you have a fat layer and a milk layer. Swirl the breast milk to combine it again after the frozen milk has thawed.

However, if the pumped milk seems chunky or the layers are still not combining after being swirled several times, it’s most likely expired breast milk and should be discarded.

Never shake the bottle

Whether you are using freshly expressed breast milk or frozen milk that has thawed, you should never shake a bottle of breast milk like you do with infant formula. 

Always swirl the milk, as breast milk has nutrients and components that are not similar to infant formula.

3. Taste test

In the same way that no two bottles of breast milk may smell the same, no two bottles may taste the same. High lipase breast milk may taste fishy, metallic, or soapy.

However, if you feel that your stored breast milk may be spoiled, you may want to conduct a taste test. If it tastes sour, it’s most likely spoiled breast milk and should not be fed to the baby.

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What happens if the baby drinks spoiled breast milk?

If your baby drinks spoiled breast milk, certain things may occur. Like when drinking spoiled cow’s milk, symptoms can appear almost immediately, indicating that the milk has gone bad.

1. Upset stomach

Expressed milk that has soured not only has a sour taste but also gives the baby an upset stomach. With only a few sips into a bottle, your little one may stop drinking milk and refuse the bottle.

Drinking spoiled milk will give most people a stomachache, and the discomfort becomes apparent quite quickly in infants. If your baby’s stomach is upset, and the bottle is still fed, other, more unpleasant symptoms may occur.

2. Baby vomits

Stored milk that has soured will often cause the infant to vomit the contents of the spoiled breast milk right back up. If your baby doesn’t have an issue with spitting up and suddenly pukes the breast milk, it may be spoiled breast milk.

3. Baby refusing to eat

If your breast milk has a bad taste, sour taste, or tastes off, your baby may refuse the bottle. If your baby drinks spoiled breast milk, it quickly kills their appetite. 

Think about it this way: If the first bite of your dinner tastes sour or spoiled, would you want to eat any more of it?

If your baby is thrashing their head to get away from the bottle, refusing to eat even though you know they are hungry, or spitting the breast milk back out at you; there is a good chance that the milk is spoiled. 

Don’t continue to force the bottle, as it could result in a tummy ache or worse.

How to prevent spoiled milk

Spoiled milk happens sometimes. Some women cannot lactate enough to keep weight on their baby, so they accept or purchase donor milk. 

Sometimes improperly labeled or stored breast milk can spoil without the mother’s knowledge. Other times, a babysitter or family member doesn’t understand how to thaw and prepare a bottle of breast milk, and it ends up spoiled.

Many things can cause your infant to be presented with spoiled milk. 

If it has happened to you or ever happens to you, try not to beat yourself up. It happens. 

Most of the time, there are no lasting and detrimental effects.

However, you can do a few things to help keep your breast milk from spoiling.

Symptoms of baby drinking spoiled breast milk and expired breast milk

1. Follow breast milk storage guidelines

Breast milk storage guidelines exist to keep breast milk from going bad and to retain the nutritional benefits as much as possible. 

While they may be confusing at first, learning the safe ways to store milk after a pumping session is of the utmost importance.

Even nursing mothers who do not pump should know them, as you never know when a pumping session may be necessary due to illness or other unforeseen circumstances.

Use proper storage containers

If you are wondering how to properly store breast milk and prevent it from spoiling, it is important to use sterilized glass or plastic storage containers. These containers should also have tight-fitting plastic lids. 

Glass containers should be cleaned regularly and sanitized with boiling water to keep milk from spoiling when frozen or refrigerated.

It is also important to also only use food-grade bottles.

Put the breast milk in the correct place

Fresh milk you want to save in the fridge for consumption at the next feeding should never be stored in the refrigerator door, where the temperature is inconsistent. 

Also, any breast milk you wish to keep for more than a few hours should be placed in a deep freezer.

2. Always swirl and smell the breast milk

As mentioned before, your milk may have a soapy or fishy smell, which is fine. However, remembering to sniff the breast milk you are preparing to feed your baby is your best course in preventing your little one from consuming bad milk.

If it smells sour at all, continue to investigate. Never dismiss an off smell.

Also, breast milk mixes easily when it’s fresh milk. Always give the bottle you are preparing for your baby a quick swirl to incorporate the layers. 

If it does not mix easily, it may be bad. If the thick fatty layer of the milk seems chunky, it’s probably not safe to feed your baby.

3. Keep an eye on it

Freshly pumped breast milk, or freshly expressed breast milk, is usually whiteish. New breast milk or breast milk with a lot of fat and nutrients that come in immediately after birth may look gold, yellow, or sometimes even orangish. Transitional milk can also look orange in color.

Mature milk can look blueish. There is nothing wrong with any of these colors. The mother’s diet can also affect the way that milk looks. 

However, if the milk looks like it has separated and hardened or looks clumpy, it’s most likely not safe for consumption and this is a large indicator of spoiled breast milk.

The color of your breast milk depends upon several factors, such as water intake, herbal consumption, how long you’ve been lactating, and your diet.

4. Clean pump parts regularly

Always clean pump parts between pumping sessions to prevent bacterial contamination in the milk or storage bag where the breast milk is kept. Also, be sure to use a food-grade storage bag. Refrain from reusing storage bags.

5. Thaw breast milk correctly

It can be painful to wait until your frozen milk bottle reaches room temperature. 

You may be tempted to put the breast milk under direct heat or use the microwave to warm it. Don’t do this, as it will cause spoiled breast milk.

If you are in a hurry and need to feed your baby, you can hold the bottle of breast milk under warm running water to help it to reach room temperature. Warm tap water can help it get the desired temperature for feeding without compromising the quality of the breast milk.

Remain diligent with breast milk

If you’ve wondered what happens if your baby drinks bad milk, hopefully, the answers have been provided. Like cow’s milk, drinking this bad milk can cause stomach pain, vomiting, and a refusal to eat.

Always store pumped breast milk carefully and properly. Likewise, let it warm to room temperature by sitting on a counter or running it under warm water.

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