Does your espresso machine froth milk well?
It’s important to start with very cold milk, and a very cold frothing pitcher. This will allow you to froth it for enough time to produce a thick foam. The milk should not be frothed past the point at which the milk hits 160 degrees Fahrenheit. If you froth the milk beyond this, it will be slightly acrid, and the bubbles won’t be consistent. This is why it’s so important to start with very cold milk and a very cold frothing pitcher – it gives you more time to blow hot air into it before it hits 165 degrees. Use a thermometer to do this until you have experience.
Don’t fill the frothing pitcher more than 1/3 of the way with cold milk. Note that a full froth (as for cappuccino) doubles the original volume of the milk. Steaming the milk (as for latte) will not add much volume to the milk, but you should have a little froth to top your drink off. For Latte Art, there should be about a half-inch (or less) of froth on top of the latte.
It’s important to drain residual water from the steam wand before frothing the milk. When your espresso machine cools down (the last time you turned it off), steam from the boiler will condense inside the steam wand. When you first turn on the steam next time you use the machine, you’ll get a spurt of hot water before you get steam. You don’t want this water in your milk. The way to do this is with a barista cloth (or old dishtowel). Hold the towel under the wand, and turn the steam on. Water will spurt out. When the steam starts, turn it off and remove the towel. Now you can froth your milk.
While the points above might be “obvious,” and are easy to do in a large coffee shop that froths lots of milk, they are more difficult to do in small quantities, at home for yourself. In particular, commercial frothing pitchers (in which thermometers work, and in which the temperature changes slowly) are big. But when you steam 4 ounces of milk to put into a 2 ounce espresso, the temperatures change quickly, and the frothing wand barely fits – this is harder to do right.
So the first point at home is to use a SMALL frothing pitcher. Our small 12 ounce pitcher is about 2 ¼ inches in diameter, and a little less than 4 inches tall. For this pitcher, 4 ounces of milk will be about 1 ¼ inches deep – this is deep enough to completely submerge the tip of the steam wand, as we would for latte.
Note that the inside height of this frothing pitcher is only 3 ½ inches. So a frothing thermometer with a 5” stem will seem way too big for it. It isn’t. What you’ll need to do is to slide the clip about half-way down the thermometer’s stem, and clip it into the frothing pitcher right next to the handle. This will put about 3 inches of the stem into the pitcher, and it will keep the stem against the wall of the pitcher so that the milk can circulate easily, and so that you can move the pitcher relative to the steam wand as needed to get a nice “swirl.”
It’s important to note that 4 ounces of milk will heat very quickly relative to the response time of the thermometer’s reading. Many frothing thermometers have a red band spanning 140-160 degrees. For large pitchers of milk (as in a commercial shop), this band alerts you to stop frothing when the thermometer drifts above 140 degrees. The thermometer’s reading will continue to climb somewhat; it shouldn’t go beyond 160 degrees.
IMPORTANT: When using a 12 ounce frothing pitcher and 4 ounces of milk, you should stop frothing when the thermometer shows 120 degrees. You’ll see a much faster response time in a 12 ounce pitcher. If you stop at 120 degrees, you’ll see the temperature continue to rise to 160. This is exactly what you want to get professional quality froth and foam.