Most espresso coffee makers whether steam boiler or pump enabled, usually come with a built in steam wand, for frothing milk to make a creamy cappuccino. The steam wand is a small solid metal pipe about 5 centimeters in length and is part of the machine design, usually sticking out from one end near the coffee shower head or group head.
The steam wand is internally connected to the boiler by a flexible pipe and forms a path for the flow of steam generated in the boiler. A valve connected between the wand and the flexible pipe provides the possibility to regulate the flow of steam. This valve is mechanical and can be controlled by hand, usually a simple knob built on the side of the machine.
These wands are similar to the ones you see in larger commercial machines in coffee shops where the barista steams up the milk in a jug to pour over an espresso shot. These commercial machines have a large boiler, therefore capable of producing larger quantities of steam needed for commercial operations. These commercial boilers are the best in terms of power to consistently provide steam for the micro-foaming of milk.
At the end of the steam wand is a small metal tip which can be unscrewed from the solid metal pipe (wand). This tip has a small hole or a few micro holes to convert the flow of steam to a sharp powerful gush. All wands whether commercial or domestic are equipped with this tip.
Froth Assisted Steam Wand
Espresso makers for homes are usually provided with froth assist steam wands. The simple version of this is an additional pipe either of metal or plastic which slides over the wand like a sheath and has a micro hole at one end to assist in the creation of air bubbles for more generous frothing.
These wands are used to compensate for the lack of large quantity of steam in commercial boilers.
Some home espresso makers also have specially designed wands with a complex tip, usually an arrangement of small holes all designed to maximize the use of steam available from the smaller boilers in these machines.
Given the smaller capacity of the boilers in home espresso machines, these wands nevertheless serve the purpose very well of frothing the milk for your creamy cappuccino. Armed with a milk frothing pitcher and some practice, these home machines are good enough for you to indulge in Latte art.
You must have noticed baristas in coffee shops always releasing some steam after frothing milk. This is to clean the steam wand of it’s internal paths to eliminate any milk that might have been sucked into the pipe immediately after frothing. Once the valve is shut, a vacuum is created in the steam wand which sucks in a small quantity of milk. This should be immediately cleaned by simply releasing some steam and wiping the wand itself with a damp cloth.
Also, periodically, descale your espresso maker with some simple household vinegar. Also, the tip can be unscrewed and the micro hole cleaned with a pin to release any milk solids that might have collected over use