Ever had a latte? Then you have experienced thick, creamy steamed milk firsthand. Ever had a cappuccino? Of course you have — you know what frothed milk looks like and how it sticks to your upper lip, perhaps creating the type of semi-embarrassing situation you’d expect to find in one of those sappy movies with Meg Ryan and Tom Hanks.
So how does one steam and froth (or "foam") milk? And more importantly, how can you? That’s what I’m going to attempt to answer here. Now I’m focusing on using a steam wand, which is a part of an espresso machine. It’s also possible to use other devices for steaming and frothing, such as a battery powered wand, or a device that looks sort of like a French press, or even a saucepan. I’m not going to explain how to use those, because I figure most of us have espresso machines that we’d rather use.
Frothing Milk (aka Foaming Milk)
Put your milk into a small pitcher, preferably a metal one. (If you’re not sure how much milk to use for the concoction you’re making, check out Cafe favorites in the recipe section.) Time to froth!
Start with the tip of the steam wand just below the surface of the milk. You want to have it low enough that it doesn’t splatter the milk too much and high enough that it creates a thick froth.
As you do this, you’ll want to keep the pitcher in motion. Move the pitcher horizontally so that the entire layer of milk gets (somewhat) evenly frothed. If you’re doing this correctly, you should hear a deep hissing sound and the froth should rise up. The resulting foam is much less dense than liquid milk because it’s full of air.
Once you’ve got the froth started, there’s no turning back, you must keep going! Well, at least until you’ve got enough froth for whatever you’re making. Once you’ve got a layer of froth in your pitcher, raise the pitcher a bit, keeping the steam wand submerged. As the froth rises up you’ll want to move down the pitcher so you don’t burn your precious foam. The process of moving the pitcher down to froth the next layer is called “stretching” (don’t ask.)
Once you’ve got your froth going, it’s time to steam. Hold the milk pitcher so that the steam wand is completely submersed. You want to open the valve enough so it creates bubbles in the milk, and use the steam wand to stir the milk at the same time. Hold the pitcher at a slight angle so the milk spins around. Don’t steam too close to the top or you’ll spray milk everywhere. Yuck.
Some people like to use thermometers for their steaming and frothing. If you’ve recently been diagnosed with obsessive-compulsive disorder, you'll definitely want to buy a thermometer for this purpose. If you don’t have a specialized milk steaming thermometer with the proper temperatures already marked on it, the milk should reach a max of 40 C (100 F) while frothing, and about 70 C (150 F) while steaming. Regardless, make sure it all stays below 80 C (175 F) to avoid burning the milk. This brings us to our next important point:
The Milk Itself
You can froth pretty much any type of milk, including soy milk, rice milk, etc. Do be warned that rice milk probably won’t froth very much. (If you have tried frothing oat milk or something, please contact me. I’m curious about the results.) Reader Chrissy wrote in to inform us that almond milk works great… who knew? All kinds of non-diary milk could work. Be warned that different brands of soy milk seem to froth differently.
In general, milk with a lower fat content is easier to deal with because it won’t burn as easily, and cold milk typically responds more easily to steam. Although milk with too little fat may not steam or foam at all! So use whatever milk you want; do what thou wilt.
One clarification on that last point — don’t try to re-use your milk. Once it’s been steamed or frothed, you’re going to have to use it or lose it. Any attempt to re-steam or re-froth will result in burned milk. Nasty.