Knowing how to use the steam wand is key to getting that creamy foam on your coffee, and giving that thick paint-like texture to your milk for latte art. It’s tempting to plunge the steam wand into the milk from the start. Don’t make this mistake. Keep the tip of the wand on the surface of the milk and let the steam do the rest. Be sure to use cold milk and check the fat content. Heavier milks make a better foam. Remember to chill your steam jug, too. You want everything to be as cold as possible before you start steaming.
To begin, surf the surface of the milk with the tip of the wand until you see the milk expanding. This is the air bubbles at work. And you want small bubbles, not big ones. You want a shaving foam effect, that creamy, consistent white foam that spreads nicely. You want to avoid a porous, sponge-like effect. Pay attention to the sound. You want a sharp hissing sound, not a high pitched shriek. Remember all the while you may have to also adjust the flow of steam for lesser or greater flow to get that hissing sound right. Once you’ve been able to place the tip just at that point into the milk on the surface when you get a hissing sound, hold it there. Keep at it a count of 15 and you will notice the milk expanding in the form of tiny bubbles. Now, keeping this position, move the cup in all directions to let the surf spread.
When you have the amount of foam you need for your coffee, only then you should bury the wand in the milk to heat it up to the temperature you require. Now you should get a soft rumbling sound.
That done, all that’s left now is to pour the milk into your coffee, saving the foam till last. And, if you’re so inclined, this is where the artist in you gets room to play. A tip: It’s best if your steam jug has a pointed spout as it makes pouring the froth much more accurate.