How to Steam Milk on a Home Espresso Machine


Photo by nixcreative
Tl;dr: Ever wondered how baristas create that perfectly steamed milk for your favorite latte or cappuccino? Learn how to steam milk at home with these simple steps and photos to guide you.
One of the biggest differences between grabbing a milk-based drink from a coffee shop versus making one at home is the quality of the milk steaming. A specialty cafe will often serve your latte brimming with a silky smooth texture on the milk's surface and even some latte art on top. So how do they do that? And can you do it at home? Well, if you've ever wondered how baristas create perfectly steamed milk, we have a guide for you. Learn to froth and steam milk (even plant-based milk) at home with these simple steps.
Note: This article assumes the use of a steaming wand from a home espresso machine. While you can create frothy milk with a milk frother, saucepan, whisk, or blender, this is for those who want to steam milk.
At its most basic, steaming milk involves inserting the steam wand of your espresso machine into a pitcher of milk and introducing air pressure (and thereby heat) until the liquid reaches the desired temperature and viscosity. This creates a frothy or creamy texture on the surface of the milk. In order to create latte art, the milk needs to be of a certain consistency. Too little aeration and not enough air, and you'll be left with a watery texture. Too much aeration, and you'll have milk with too much foam and too many microbubbles for quality latte art.
Step 1: Aeration
Photo by Anna Tarazevich
Creating perfectly steamed milk starts with aeration (or the amount of air you introduce into the milk pitcher), then a nice whirlpool, finished with a good temperature.
- The first step is to purge the steam wand of any leftover milk or debris from the last steaming. Take a clean kitchen towel or bar towel from your counter and hold it over the steam wand so as not to burn yourself. Gently turn on the steam wand for 1-2 seconds for a quick "purge." This ensures no old milk making it into the fresh drink.
- Next, insert the tip of the steam wand into the top left corner of the pitcher. The pitcher should be appropriately dosed with the right amount of cold milk for the size of the drink. The tip of the wand should be just below the surface, approximately 1/2 inch. If it's all the way to the bottom of the pitcher, the air pressure will rocket off the bottom of the stainless steel pitcher and create an unpleasant grinding sound. It will sound like metal on metal (I'm sure we've all heard the sound).
- Next, turn your espresso knob on or flip the steam wand button and immediately begin aerating the milk at the surface. This initial aeration should be 1-3 seconds for a latte, mocha, cortado, or other milk-based drink and 5-6 seconds for a cappuccino. That's all. It doesn't take much time. After the initial aeration, move the pitcher up the steam wand so the wand is approximately one inch below the surface. A cappuccino needs more aeration to create milk with a slightly foamier texture. (As a reminder, a true cappuccino is made up of ⅓ espresso, ⅓ steamed milk, and ⅓ foam. If you steam a cappuccino right, the layers will unfold automatically without needing to spoon the foam on top.)
- After the pitcher moves up the steam wand, there should be a swirling motion that spins the milk around the pitcher in a whirlpool. This will be more obvious with larger drinks and hard to see with smaller drinks. As the milk swirls, slowly move the pitcher up and down the steam wand to eat up tiny microbubbles in the vortex that were created in the initial aeration. Stop when the milk reaches the desired temperature.
- Wipe the wand clean and stamp the pitcher on the counter to get rid of any large bubbles.
Step 2: Temperature
Photo by tum3123
The ideal milk temperature for a coffee beverage should be between 130-160°F. 130°F is on the low end, and 160°F is on the high end. You can use a thermometer at first, but a general rule is to steam the milk until the side of the pitcher is too hot to touch. Some people prefer extra-hot drinks and will specify a certain temperature, but it's important to know that the sweet spot for dairy milk is between 140 and 150°F; this is when the milk will taste sweeter as it heats. If the milk is steamed too hot, it will taste burnt.
Another tip is to make sure the steam valve pressure is high enough to heat and swirl the drink, especially if using a heat exchanger.
Step 3: Pouring
Latte art. Tilt the cup and move closer to the surface to make latte art. Photo by Chevanon Photography
Hold the espresso cup with one hand and the milk steaming pitcher in the other. Slowly pour from higher above the cup to start (six inches or so), as this will create our first layer of contrast. The white milk will bury itself under the brown espresso until we want it to emerge. Tilt the cup as the coffee fills to halfway up and then move slowly toward the surface.
From here, what you do will depend on what kind of latte art design you want. If you're looking to pour a rosetta, slowly start to shake the pitcher from side to side and move backward. This is overly simplistic, of course, so be sure to check out other articles on how to pour latte art! Then, strikethrough with a slow but deliberate forward motion. Then move on to tulips, hearts, and even swans!
Tips & Tricks
Plant Based Milks
Photo by Rimma Bondarenko
The best milk for espresso-based drinks has traditionally been whole milk. Whole milk has the right fat content to create sweet and creamy frothed milk. Yet, pretty much all of the above will apply to alternative or plant-based milks. The consensus today is that oat milk can steam just as well as other barista-based plant options. For better art, make sure to let oat milk rest for 10-20 seconds before pouring. Almond and Soy milk have a tendency to get a little too foamy, so watch aeration and steam for less time overall. Skim milk and coconut tend to be on the watery side.
Steaming Pitcher
Photo by Nopphadon Jantranapaporn
Important note. A steaming pitcher needs to have a certain angle of spout in order to latte art. If there’s hardly any notch where you pour, the milk will have a tendency to splash out of the pitcher. Think of it like the difference between a gooseneck water kettle and a basic water kettle with no flow.
Reach Out to a Curated Expert
The entire milk steaming process takes less than twenty seconds, so it can be hard to get right at first, but with a little practice, you'll get better each time.
If you have any questions about the process or anything espresso-related, reach out to a Curated Coffee & Espresso Expert!