is buttermilk supposed to smell sour

Is buttermilk supposed to smell sour? Buttermilk is a dairy product that is made from cow’s milk. It is used in baking and has a sour smell to it.

Some people wonder if buttermilk is supposed to smell sour or if there is something wrong with it.

Lactose is consumed by the bacteria that ferment the lactose in milk, giving buttermilk its distinct sour flavor. This produces lactic acid, which lowers the pH of the dairy.

Even though buttermilk has an acidic and sour odor, it should not be very sour unless it has gone bad.

This blog post will discuss the smell of buttermilk and what it means if your buttermilk smells sour.

What’s Buttermilk?

the buttermilk

Buttermilk is produced from the liquid that is discarded after the production of butter.

People often use a separator device to extract the cream from the remainder of the liquid milk after they have pushed the milk through it.

This cream is then placed into a churner and spun over and over again until the butter and buttermilk are completely separated from one another.

Is Buttermilk Supposed To Smell Sour?

Buttermilk is a dairy product that has been around for centuries. It is made by adding bacteria to milk and allowing it to ferment.

This gives buttermilk a sour smell. We use buttermilk a lot in our daily lives.

It can be drunk straight or used as an ingredient in cooking. It goes well with fried salads, foods, and smoothies, among other things.

However, buttermilk is not made from milk but from the liquid leftover after making butter.

Note: It turns into a thick, bitter cream because it ferments. The smell and taste of the finished product are both powerful.

What Does Buttermilk Smell Like?

what does it smell

The buttermilk process gives buttermilk its distinct sour smell. But what does this sour smell mean?

Is it safe to drink? Let’s look at the science behind buttermilk’s signature scent.

1. The Milk’s Fat Content

Buttermilks with a lower fat percentage will have a more muted aroma because fatty acids have a lower volatility threshold and are more susceptible to oxidation.

In contrast, buttermilks with a higher fat content would have a stronger odor.

2. The Level of Lactic Acid in the Buttermilk

The sour flavor of buttermilk may be attributed, in part, to lactic acid, which is a byproduct of the fermentation process.

In addition, it has a sharp odor that is especially noticeable in buttermilks that have a more significant proportion of lactic acid in their composition.

3. The Presence of Other Bacteria

presence of bacteria

Buttermilk may take on a variety of smells due to the presence of several types of bacteria.

For instance, the bacteria Lactococcus lactis generate a smell similar to butter.

However, it may be a touch sourer than Leuconostoc cremoris’s fragrance, which is a sour smell.

4. The Type of Culture Used

Buttermilk may have a range of smells according to the present cultures.

For example, the bacterium Butyrivibrio fibrisolvens provides a fruity scent, but the bacteria Streptococcus lactis gives a cheesy smell.

5. The Storage Conditions

Bacteria proliferate and emit more smells at higher temperatures.

So, buttermilk that is kept at a higher temperature will have a greater sour smell than buttermilk stored at a lower temperature.

Does Buttermilk Go Bad?

buttermilk go bad

Buttermilk goes bad, just like any other kind of dairy.

Bacteria keep fermenting as time goes on, and they can reach levels that are dangerous enough to make you sick.

So, it’s best to eat your carton of milk within three weeks of opening it. Dates of expiration should also be looked at.

Signs That You Should Throw Away Your Product


Buttermilk usually smells sourer and stronger than milk. If buttermilk smells sour, you’ll know it’s gone bad.

If the buttermilk has been bad for a few days, the sour smell will probably be strong enough to make you want to pour it out right away.


the texture

Bad buttermilk may be identified by its texture. Rancid buttermilk resembles milk.

It becomes thick and chunky instead of typical. It’s thick and cottage cheese-like.

Once buttermilk becomes thick and chunky, it must be discarded. Do not worry if you notice lumps in your freshly opened buttermilk carton.

Buttermilk separates them. Buttermilk lumps won’t.


It is most likely bad if the buttermilk lacks this creamy, buttery flavor.

It may also have a sour flavor to it. If the buttermilk tastes sour, it should not be used.

Expiration Date

the expiration date

It is usually a good idea to check the expiration date on buttermilk before using it. Buttermilk is often purchased fresh since it is a dairy product.

If the buttermilk is over its expiry date, it should be discarded. Although it may seem and smell fine, fresh food has an expiration date.

Note: Foodborne illness is more prevalent if you ingest food beyond its expiry date.

How to Make Buttermilk Last Longer.

Here are some tips for extending the life of your buttermilk,


be refrigerated

Buttermilk should be refrigerated and not left out at room temperature.

If you do not use the buttermilk right away, keep it unopened since an opened carton of buttermilk will not survive as long as an unopened one.

While using buttermilk, keep your fingers away from the lid when pouring.

Never consume buttermilk straight from the carton, since this might introduce bacteria and hasten the deterioration of the product.

Buttermilk Powder

If you’re weary of your buttermilk spoiling before you’ve finished it, try powdered buttermilk.

It has a relatively long shelf life at room temperature, and there is no waste since you can make just what you need.

Rather than being ingested, powdered buttermilk is widely used in baked goods, and replacements for buttermilk may also be used.

Keeping Buttermilk Clean

keep clean

We suggest against mixing anything with your buttermilk since this might shorten its shelf life.

To prevent introducing germs into your buttermilk, always pour it with clean hands.


You may also freeze buttermilk to extend its shelf life even more.

Because freezing changes the consistency and may cause the buttermilk to clump and separate, it is recommended not to use frozen buttermilk for drinking or uncooked dishes.

However, frozen buttermilk will retain its acidity level, which most people want when using it for baking since it aids in the rising of baked goods.

Buttermilk may be stored in the freezer for up to two months; however, the quality will quickly decline.

You may marinate meat in frozen buttermilk to make it softer, either overnight or for a few hours.

I’d also recommend storing your buttermilk in an airtight container to extend its shelf life.

FAQs About Is Buttermilk Supposed To Smell Sour

popular questions about buttermilk

Do you have any other questions about does buttermilk smell sour? Please keep us informed.

Here are some of the most commonly asked questions about buttermilk.

How Long Can Buttermilk Be Stored?

Buttermilk should always be kept refrigerated as a precaution. It should never be left out for more than two hours at room temperature.

If the temperature exceeds 90 degrees F, this time is reduced to one hour.

You don’t want to consume or prepare a spoiled product. Food poisoning is an unpleasant experience.

Is It Possible to Freeze Buttermilk?

Freezing leftover buttermilk is an excellent technique to prevent food waste while saving money.

If properly frozen, it may survive up to three months. You may use ice cube trays or muffin pans that you already have at home.

Is It Normal for Buttermilk To Be Lumpy?

Buttermilk normally has some little lumps and clumps that may be whisked away, but don’t use it if it gets excessively thick and impossible to pour.

Final Verdict

So, is buttermilk supposed to smell sour? The answer is yes!

Buttermilk is a fermented dairy product, and the sour smell is simply the result of the fermentation process.

However, if your buttermilk starts to smell particularly strong or unpleasant, it may be past its expiration date, and you should discard it.

Otherwise, enjoy your sour-smelling buttermilk in all of your favorite recipes!

Thanks for reading!