Cappuccinos, lattes, macchiatos, flat whites—milk-based coffee is just that: milk and coffee. But the microfoam varies significantly from cup to cup.
What is microfoam?
Microfoam is the finely textured, heated milk used to make espresso-based coffee drinks like cappuccinos and flat whites, and is particularly used in latte art.
It is usually made with hot steam from a Barista espresso machine, which pumps steam into a milk jug.
Good microfoam is like wet paint. It's velvety and silky, making it the perfect milk to pour into a cup and create great latte art.
How to make microfoam with a steam wand?
- Lower the tip of the steam wand just below the surface of the milk. This will shield you from the sound and also ensure you create a rippling current in the milk. This helps break up the air and create a beautiful, creamy microfoam.
- Add air to the milk. You can do this by bringing the tip of the steam wand to the surface until you hear a ripping sound. The goal is to create a latex-like consistency and texture throughout the foam. Warning: Don't lift the wand too far from the pitcher. You may create bubbles on the surface of the milk or cause it to splatter.
- Get the milk moving. At this point, when you've added enough air, lower the tip of the whisk just below the surface of the milk again and get the milk moving. Find a stable spot and be patient. Movement is essential, as it helps break up large bubbles and gives the foam a nice, even mix.
- Don't overheat the milk. Be careful not to burn it. When you're done, pour the velvety foam over the espresso and enjoy.
The temperature of the milk
Milk temperature is complicated and there are many factors involved, but it's arguably the most important factor to consider when steaming milk. If it's too hot, it will result in a smooth, velvety texture. If it's too cold, the foam won't have a good consistency.
Understanding the correct milk temperature depends on the brand and quality of the milk you use. Whole milk will contain more fat and, consequently, require a longer period of time to heat, but there are some guidelines to keep in mind.
For example, regular cow's milk consists of two types of proteins: casein (which accounts for approximately 80 percent of the milk) and whey protein (which makes up the remaining 20 percent). Coffee experts suggest that steaming milk should ideally be between 140 and 160 degrees Fahrenheit.
However, many specialty coffee shops will steam milk at a lower temperature to preserve texture and flavor.
Microfoam at home
There are three ways to do this. The quickest and easiest way to create a good microfoam is to invest in an automatic milk frother.
This device not only warms the milk for you, but also creates the desired level of foam in minutes. A cheaper alternative to achieve similar results at a fraction of the cost is to extract warm milk in a French press.
Finally, you can use a handheld steamer to froth the milk by hand. This is a last resort option, as it's difficult to achieve any fine bubbles with this device.
As you can see, there are several rules to follow to produce good microfoam. Many coffee shops don't really understand how to make it, and as a result, they end up sacrificing the quality of the coffee they offer.
While microfoam requires a great deal of precision to perfect and is an art, the reward far outweighs the risk of error, because there's nothing like a velvety smooth cup of coffee.