What does frothing milk do?

In this brief article we will answer the question what does frothing milk do and three benefits of frothing milk

What does frothing milk do?

Frothing a milk makes it sweeter and better in taste by making it stable. When milk is heated the lactose in it dissolves more readily and gives it a sweeter taste. It also impacts the fat percentage making the milk more stable than skimmed milk

What is the frothing of milk?

Frothing of milk is aerating the milk with the help of a frother. A frother is a utensil which is typically used when frothing milk for coffee. In the process of frothing, heated milk is whisked and mixed.

The process of frothing aerates the milk and creates a thick foam like structure. There are tiny bubbles on the surface of milk after frothing, these bubbles make the texture of milk lighter and increases its volume

Effects of frothing on milk:

Frothing of milk has a significant effect on the ingredients of milk including fats and proteins. It affects the ingredients as:

Effect on fat:

In case of skim milk the fat content is reduced to almost non-existent. But in the case of 1% or 2% milk there are amounts of fat present in them. In milk the fatter, the richer and creamier milk becomes. When milk is frothed the fat content are effected and milk become more voluminous. A 5% milk is most stable, frothier, thick and voluminous in nature

Effects on Protein:

There are two types of proteins in milk called whey and Casein. Both of these proteins interact with water when milk is frothed. The structural change in milk after frothing happens because of the change in structure of these proteins. Heat denatures the protein and they interact with surroundings which make the milk more stable and improves the texture

Effects on Lactose:

Lactose is the sugar of milk and is present in milk at all temperatures. But it is less soluble with milk at low temperature and rarely imparts a taste when milk is cold. But when milk is heated in frothing it affects the solubility of lactose. This effect on lactose makes the milk sweeter once it is heated.

Benefits of frothing:

Makes milk stable:

The foam is made by water vapors and air particles in milk. The protein of milk creates a sphere around the air particles and stabilizes the bubble. Hence giving milk the stability, as proteins have chains in milk which are polar. The bond created between the hydrophilic part of protein and water is strong. Similarly, the bond between the hydrophobic part of protein and milk particles is strong. This increases the stability of milk and produces a foamy structure

Better taste for espresso:

Espresso is made of coffee and milk mixed together and sometimes sugar is added per need. Espresso has a creamy, rich, sweet mouthfeel to it which is a major reason for its liking among people. But this creamy texture is not because of the grinded coffee but frothy milk.

A frothy milk is preferred over skim milk when baristas are choosing milk for espresso. Frothy milk has a rich taste to it, is lighter and has air bubbles in it. All of these properties a cup of espresso tasty and foamy.

Enhances the flavor:

Another benefit of frothing heated milk is that it makes the milk tasty. The formation of small bubbles of water vapors and air in the milk increases the volume. These air bubbles are formed when milk is aerated with the help of a frother.

Another advantage of tiny bubbles is increasing the surface area of the bubbles. With increase in volume, the surface area of milk’s sip increases. This increase ensures that there is maximum surface tension between mixtures in liquid beverages. It also increases the surface contact between taste buds and beverage hence increasing the flavor of milk

These are some of the benefits of heating the milk and frothing it when making coffee. Frothing of milk also improves the lactose interaction in milk and exposes it to the milk surface. This makes the milk taste sweeter and better. That’s why frothing of milk is preferred over ordinary heating of milk

Frothing vs Steaming:

Frothed milk has a voluminous look and is lighter in nature, on the other hand steamed milk is heated but very little aerated. The difference in the degree of aeration effects greatly on quality especially if you are using the milk for coffee.

In steamed milk the milk is heated to a high temperature but not aerated so a small amount of micro foams is formed. In case of frothing of the milk the air bubbles ensure a large amount of micro foams. That’s why frothy milk is chosen when making coffee but some varieties of coffees are also made of steamed milk.


In this brief article we have answered the question what does frothing milk do and three benefits of frothing milk





Hi, I am Charlotte, I love cooking and in my previous life, I was a chef. I bring some of my experience to the recipes on this hub and answer your food questions.

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