Buttermilk vs Milk – Difference and Comparison

Published Categorized as Ingredients

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Being given a glass of milk and a glass of buttermilk, it may be quite hard to distinguish which one is which. In fact, many people believe you can substitute one for the other quite easily without it creating any difference to what you are doing with the milk.

Both are often called for in recipes, both can be used to drink, both can be used in baking, but in most cases, the specification of which one is needed is actually due to a number of reasons.

Buttermilk and regular milk both hold individual qualities which make them better for different uses. Today I am going to look at what is the difference between milk and buttermilk and tell you just how to use each to their potential. Not only will your milk knowledge increase, but your cooking will too once you know these easy little facts!

Table of Contents

Where Does Milk Come From?

To firstly understand the differences between buttermilk and milk, it is useful to know where each product comes from, how it is processed, and how it is produced.

Buttermilk vs Milk_Alice Kitchen

How is Milk Produced?

Regular milk is a natural product that comes from the mammary glands of an animal – in most instances this is simply the udder of a cow. However, you do get milk from many animals that are used for human consumption, but today I am going to focus primarily on cow’s milk to keep things simple.

Once a cow has been milked, the milk has to undergo processing to not only make it taste better so that it is drinkable, but to also improve the shelf-life, texture, consistency and appearance. Although many people do drink milk that comes straight from the animal, this can put you at risk of getting a disease from the bacteria, such as e. coli and salmonella.

Raw milk also does not taste or have the same consistency of the milk we are used to. It is a lot fattier, creamier, and has a much stronger taste. Although this may seem appealing, milk goes through pasteurization before it is put on our shelves for both the safety of our health, and also so that it can come in a variety of fat levels, thickness and strength in taste.

Pasteurization is a process that heats the milk up for a long period of time. This heat kills the bacteria and helps extend the shelf life. It is then homogenized, which means that it is put under pressure to make the texture consistent and to stop the cream from separating – something can begin to happen as your milk goes out of date.

Certain milk can also go through centrifugal separation. This is done to separate the fat globules from the rest of the milk and is specifically used for skimmed, low-fat, or reduced-fat milk.

Once milk has gone through these various steps, it is packaged up and sold on the shelves of almost any grocery store you go into.

Buttermilk vs Milk_Alice Kitchen

How is Buttermilk Produced?

Traditionally, buttermilk is the liquid that remains after churning the butter out of cream, creating a fermented dairy drink. Buttermilk is a lot more common in warmer climates, as unrefrigerated milk will become sour more quickly.

Because buttermilk is the liquid leftover after the butter is scooped out, it has quite a rich flavor but is still very low in fat, as all of the fat ends up in the butter. It is full of healthy cultures (harmless lactic acid bacteria) that develop naturally when cream is left at room temperature.

However, as time has gone on, it is not as common for butter to be made in small quantities in churns, and so the rich tasting liquid that is buttermilk, is no longer developed. Instead, buttermilk is developed by most dairies these days by using regular, pasteurized milk like the milk mentioned above, and combining it with cultures.

This can then be bought in bottles and cartons in grocery stores. Store-bought buttermilk is often thicker and tangier than traditionally made buttermilk, so if a recipe calls for it then you should try to stick to store-bought to ensure it has the correct flavour and acidity. The acid in buttermilk helps with the leavening of the recipe, so many recipes will also require baking soda to help balance this out.

You can also buy powdered buttermilk which is just as good, and also lasts longer.

You can make your own buttermilk at home by adding lemon juice to regular, pasteurized milk.

Texture and Appearance

So, now that we know how both milks are produced, you would think it would be easy to tell the difference. In some instances, this is the case, however, in appearance and texture they are quite similar.

Once pasteurized, milk becomes quite thin, similar to buttermilk, and so they have an extremely similar texture. Both should be quite smooth, however in some cases, particularly if you are comparing low-fat milk with buttermilk, the buttermilk will be slightly denser.

Both are a regular, white color. Sometimes buttermilk can have a slight yellow tone to it, especially if you decide to make your own, but overall they are almost identical in color. However, buttermilk tends to leave a thicker residue on the glass or bottle of which it is in. Although milk leaves a slight residue on the glass, this is a lot more prominent with buttermilk.


Next up, and probably the best method to use when comparing them, is the taste test. Due to the cultures in buttermilk, it has quite a sour yet sweet flavor. The cultures give it an acidic taste that you may actually mistake for slightly off milk if you drink it by mistake.

Milk, whilst it varies in flavor depending on the fat levels, has quite a normal, creamy flavor that is loved by people across the globe. Buttermilk, on the other hand, is less popular and more a matter of preference.


Whilst it depends on what kind of pasteurized milk you have, the below comparisons are related to regular, whole milk vs buttermilk. Both milks weigh about the same, and so comparing them is quite easy.

One cup of whole milk contains the following:

  • Calories: 156
  • Protein: 8g
  • Fat: 9g
  • Carbohydrates: 11g

One cup of buttermilk contains the following:

  • Calories: 99
  • Protein: 8g
  • Fat: 2.2g
  • Carbohydrates: 12g

We can see that whilst both milks sit quite similar in protein and carbohydrates, they differ quite dramatically in terms of calories and fat content. This is because all of the fat goes into the butter when buttermilk is made, and so the buttermilk is what is leftover and does not hold much remaining fat.

Both are high in protein and carbohydrates. Because buttermilk is a lot lower in fat, it is often a popular choice for people dieting. However, the low-fat content makes it a useless alternative for people on a keto diet, so they usually would opt for something else.

Uses of Buttermilk and Milk

Having established some of the key differences between the production and performance of each milk, it makes sense to now compare their uses. This is where the two milks really do differentiate and why they both exist separately for different reasons.

Buttermilk vs Milk_Alice Kitchen

What is buttermilk used for?

Buttermilk is often enjoyed on its own, in a glass, as a drink. It is as simple as that. People like the unique flavor to it, and it has a lot less fat in it, making it a much healthier option for anyone who is watching their weight.

Buttermilk is also great in baking. This is because it has a longer shelf life than regular milk due to the acidity in it. This means that baking with buttermilk can help preserve what you are making as the milk does not go off as quickly.

The acidity in buttermilk also helps to break down gluten. This means it can be great to use in cakes, and certain breads, as it creates a much lighter, fluffier mix. Buttermilk is a popular choice in a lot of baking, and in products like pancakes – as we all like these as fluffy as possible!

The sour flavor of buttermilk can add a unique twist to your cooking and baking, but if used in small quantities it won’t change the taste too much. Some people like to use it in sauces in place of regular milk as it brings a tangy flavor.

What is Milk Used For?

Of course there is the obvious – drinking and acting as a great source of calcium and a perfect dip for your cookies. Milk is a really popular choice with kids as they grow up and then as we get older, we tend to drink it less on its own, and more in our drinks like tea and coffee. It works as a great neutralizer for stronger flavors.

Then we also have the use of milk being the base of much of our loved dairy products. From milk we then have cheese, yogurt, sour cream, butter – just about anything dairy is usually a product of milk.

Then we use milk to help moisten our foods. We use it on cereal or in sauces as it brings a slightly creamier texture and flavor to things and again, it can help neutralize the things we are cooking, particularly if they are spicy. In many instances though, people will tend to use cream instead of milk as it is richer in flavor and consistency.

Can I Replace Buttermilk with Milk?

Replacing one for the other will usually turn out fine. Of course they have slightly different flavors, but if used in cooking or baking this will not make much difference to the taste.

To have as a drink, buttermilk has that slightly more acidic taste, and so this is really a matter of preference. Of course it is important to keep in mind the difference in fat content and calories, particularly if you are sticking to a certain diet. In fact, their nutritional differences are important to keep in mind whenever you swap one for the other no matter what this is for.

Their similar texture means that they won’t alter recipes too much if replaced with each other. However, the acidity in buttermilk can work as a leavening agent in baking, and so this is definitely an important factor to consider. You will not gain the same gluten breakdown with regular milk, which means your final product may not be as light and fluffy.

Buttermilk vs Milk

So, in conclusion, they are pretty similar. Both are the product of a cow, and both are of the same consistency and appearance. Whilst you can make your own buttermilk using pasteurized milk, it is much more difficult to make your own milk.

They can be swapped for each other in most instances, however there are a few things to bear in mind if you are swapping your milk for buttermilk.

Buttermilk has a tangier flavor, and so if drinking alone, this may not be something you desire. Whilst it won’t impact your cooking and baking too much in flavor, it can shine through if you are using weaker flavors or if the milk is playing a large part in your recipe.

If you are comparing whole milk vs buttermilk in baking, then the acidity of buttermilk makes it a wonderful agent in baking, and so often people would prefer to stick to buttermilk over milk here. This will result in a much lighter and more enjoyable cake or bread.

The processes of creating both milks differ extremely. Whilst buttermilk is a byproduct of butter, milk is the starting point for almost all dairy foods. Pasteurized milk is a lot more common, due to its creamy and smooth consistency, however buttermilk does have its own benefits.

When looking at nutrition, buttermilk wins in the department for weight loss. The process of how buttermilk is made means that hardly any fat is left in it compared to regular milk. This is important to remember whenever you are considering substituting one for the other.

Overall, if you do use milk as a buttermilk substitute, it won’t make too much difference. If you are stuck with only one option, don’t worry! If you are baking, buttermilk usually works as a better alternative, but if you are drinking it or using it on your cereal, regular milk is the go-to. Whatever your preference, they both work perfectly well for just about anything!


Can I substitute buttermilk for milk?

Substituting buttermilk for milk will usually cause no problems. It is important to remember that buttermilk has a slightly sour flavor though, and also has a much lower fat content. If used in baking, the acidity of buttermilk helps break down the gluten more, and so swapping for regular milk may end up in your cakes or bread not having the same rise to them.

What happens if you use regular milk instead of buttermilk?

Usually this will not alter things too much. Using regular milk will increase the fat content of whatever you are making. It will also have a creamier, sweeter flavor than buttermilk. However, if you are working with gluten and decide to use regular milk instead of buttermilk, you will end up with a denser final product due to the lack of gluten breakdown.

Which is more nutritious milk or buttermilk?

Whilst both are rich in protein, milk is slightly higher in calcium (but not by very much), however it is also a lot higher in fat and calories. If looking at fat content, buttermilk would be considered more nutritious.