The objective of milk steaming and foaming is to
produce a firm, semi-liquid velvety milk foam, ideal for
cappuccinos and lattes. This is achieved by the use of heat and
air, by way of steam.
Always use a stainless steel straight sided or bell-bottomed jug
for your milk frothing. Never use plastic, glass or china jugs.
Stainless steel offers good heat transfer which is an essential
part of the process. Always use chilled fresh milk – milk will take
in air easier if it is cold. Full fat milk produces a denser,
longer lasting foam than low fat milk, but this is personal
preference. Make sure the jug is half full or less, as the volume
of milk will double during the frothing process.
The first thing to do is to purge the steam wand of any water
residue, making sure that none of the steam jets are blocked and
position the wand so that it will allow the jug to easily pass
under the tip. Centre the tip of the steam wand of your espresso
machine on the milk surface and submerge it by 1 cm (half an
Turn the steam valve fully on. Holding the jug in both hands,
gently adjust the depth of the wand tip until you hear a distinct
“tssss tssss” sound which indicates that air is being drawn into
the milk. The milk level should rise quickly as it expands or
stretches. As this happens, lower the jug slowly, keeping the tip
just below the surface at all times.
If the milk bubbles too fiercely and spits then the tip is too
high and you should raise the jug slightly, however if you hear a
screech then there is insufficient volume of steam so you should
lower the jug slightly. During this process try to avoid breaking
the surface of the milk with the tip as this can introduce large
bubbles into the mixture and spoil its texture.
To complete the process, lower the tip of the steam wand (by
raising the jug) towards the bottom of the jug and at the same time
move the wand to one side of the jug. The milk should start to
swirl and you should hear a high pitched growl. This adds texture
to the mixture as many tiny bubbles are formed.
Continue to swirl the milk in this way until the side of the jug
is too hot to touch comfortably and the growl becomes a low purr.
Turn off the steam quickly with the wand tip still submerged.
Remove the wand and wipe clean immediately. Tap the jug on the
counter and swirl the jug around gently. You should have a jug of
firm, velvety foam over hot steamed milk.
Pour the mixture over an espresso by gently rocking the jug from
side to side to ensure the right combination of hot milk and foam
is delivered into the cup. Enjoy.
Written by Fenton Wayne - (Fenton Wayne is an independent advisor
in the coffee and vending trade where he has over 25 years
experience. This article has been submitted to and distributed