How to froth milk with an espresso machine? – For as long as we can remember, coffee and milk have gone hand in hand. Across different cultures, different forms of milk have been used to accompany coffee, one of the world’s most popular beverages. One of the most notable coffee cultures is that of Italian coffee culture, where some of our favourite espresso drinks like Lattes and Cappuccinos are now part of our everyday routine. Although many of us know how to enjoy these beverages, not all of us know how milk frothing works, and how exactly our favourite speciality coffee shops create that rich and creamy texture in the steamed milk used for Latte Art. In theory, the concept is simple – Using the steam wand on the espresso machine, the jet of steam swirls the milk and breaks the surface of the milk in the frothing pitcher, incorporating air into the milk and increasing its volume, while simultaneously heating the milk. However, each step of the process presents its own set of considerations.
Preparing to froth milk – Choosing the right milk
The first step to frothing milk with an espresso machine is to choose the appropriate type of milk. In most speciality coffee shops and gourmet cafes around the world, fresh milk is used. This is also known as full cream milk. Usually, the fat content of the fresh milk sits at between 3.2% to 3.5% and possesses a good amount of fat and milk solids to adequately create the rich and creamy texture desired in espresso-based milk drinks. For this reason, fresh milk or full cream milk is recommended for this process. If low-fat milk or skim milk is preferred to full cream milk, it is also possible to create froth milk. However, do note that because of the lower fat and protein content, the milk frothing process might take a slightly longer time, and may not produce as rich or as creamy a texture as full cream milk.
Preparing to froth milk – Tools and equipment
Once you have decided on the type of milk you wish to use for the milk frothing process. You should dispense the milk into a milk pitcher that is designed for milk frothing and milk steaming. These are typically made of metal, and may or may not be powder coated with colour. For milk frothing purposes, metal is preferable to other materials, as you will want to keep watch over the temperature of the milk during the frothing process. While you may use a thermometer to do so, it is common for baristas to use their hands, placed against the metal pitcher as a gauge of temperature – Thus the preference for metal milk frothing pitcher. On the espresso machine itself, you will want to purge the steam wand before placing it into your milk pitcher. This is because, after a where the steam wand is not used, water will start to build up within the steam wand. The purging of the steam wand is meant to get rid of this excess water so that it does not enter your milk pitcher and dilute the milk unnecessarily. When purging the steam wand, it is a good idea to point the tip of the steam wand into the drip tray, so that the hot water and steam exiting the steam wand does not scald you.
Frothing the milk with an espresso machine
Once you have purged the steam wand of any excess water, it is time to steam your milk. Position the steam wand at a comfortable angle for you, and raise your milk frothing pitcher into the steam wand so that the steam wand sits at a 45-degree angle. Turn on the steam wand fully to allow for an unobstructed flow of steam to travel from the boiler of the espresso machine, through the steam wand, and into the cold milk.
At this point, the steam passing into the milk should start to swirl the milk – this is an important step. When the milk starts to swirl, the surface of the milk is broken and the air is being incorporated into the milk, increasing its volume. At the same time, the milk is also being heated up from the steam that is entering the milk. While doing this, place your free hand around the milk frothing pitcher – stop steaming the milk when the temperature of the pitcher just becomes unbearable to touch. During the process, if there is no swirl happening at the surface of the milk, it may be because your steam wand is inserted too deep into the milk frothing pitcher.
On the flip side, if you hear an excessive amount of “hissing” from the steam wand, it is indicative that your steam wand is catching too much air into the milk, which will make the frothed milk too airy and undesirable. Once done, remove the milk pitcher from the steam wand, and wipe down the steam wand with a damp cloth. Also, purge the steam wand to get rid of any excess milk that might be left in the steam wand nozzle. If done correctly, you should notice that your cold milk is now hot, and has increased in volume. You might also notice that it now has a thicker consistency than before, and develop a sheen on the surface. On occasion, you might find that above the smooth sheen on the milk surface, there are still some larger bubbles. A quick and easy way to get rid of these bubbles would be to swirl the steamed milk inside the pitcher, and also tap the bottom of the pitcher onto your workstation counter or surface. This should help to break apart the air bubbles to get you a smooth and creamy consistency for your steamed milk. Combine with your espresso shot for your favourite milk-based espresso drinks.