The Secrets of Steamed Milk

Posted: Sep 28, 2016

The Secrets of Steamed Milk

Espresso, water, and milk form the foundation for every espresso drink out there, from the cubano to the peppermint mocha. Espresso is typically the focus, its complexity and sensitivity makes for a delicious line of questioning, but milk has it’s own subtleties that are rarely explored.

If you’re sipping on a hot drink, chances are it’s made with steamed milk – milk that has been both heated and filled with tiny air bubbles to give it a thick, velvety texture.It’s a gorgeous way to enjoy espresso, and the experience changes with the type of milk used, yielding a variety of options.

Today, we’re delving into the science of milk, steaming vs. heating, and the best ways to achieve the effect at home. Buckle up!

Milk is a solution – it’s made up of various types of fats, proteins, and sugarsfloating around in water. Each of these three groups play a part in trapping and sustaining microfoam bubbles. Milk is typically steamed with a steam wand – a narrow pipe with tiny holes at the tip that releases, well, steam. These tiny jets of super-hot H2O are held against the surface of the milk, so air is caught and pushed into the liquid. After a few seconds – or when the milk hits 95℉ or so – the tip of the steam wand is submerged fully, forcing the milk to whirlpool, and heating it to between 130℉ and 160℉. (Anything above 160℉ scalds the milk.)

Several things happen all at once.

The proteins unravel and form shells around the new air bubbles

The fats become more soluble and reinforce the protein shells

And the sugars – particularly lactose – break down into simple sugars, which are sweeter to the taste.

The result is called microfoam – a dense cloud of tiny bubbles suspended in milk.

The more air added to the milk, the bigger the bubbles, and the stiffer the foam, but for most espresso drinks, the goal is a silky texture and smooth, glossy pour.

Some home espresso machine have a steam wand included, but for most of us, the precision and power available to baristas doesn’t follow up home.

Thankfully, there are some options out there! Here are our two favorites:

Stovetop Method

You’ll need:

• saucepan
• milk
• milk frother (This one is a great option)

Instructions:

1. Portion out enough milk for your purposes, and heat over a low setting in a saucepan.
2. When it starts to steam – but before it bubbles – submerge the milk frother in the milk, turn it on, and create a whirlpool until you’ve hit the desired amount of foam.

French Press Method

You’ll need:

• a French Press
• milk

Instructions:

1. Heat milk over the stove or in microwave until steaming.
2. Pour into a clean french press, and vigorously pump the top up and down for about twenty seconds.

You’re one step closer to being a fully fledged home barista! Share your favorite milk techniques with us this week!