A stove top espresso machine is probably the most inexpensive mechanism for which to make
an espresso. Costing around US$25 for a cheap model they can effectively make a real
coffee in your house or while camping.
Made of Aluminium or stainless steel (this is better, but more expensive), they come in many shapes and sizes but the principle behind their operation is
\ ____ / |
\ / | /_____ Handle
\finished| | / | \
\product| | / /________ Top Part
\ | | / \
\_____| |_____/ /____________ Filter
/|coffee grind|\ \
/ |____ _____| \_
/ | | \ Safety valve
/ | | \
/ water | | \ /_________ Bottom Part
The machine is put on an element or flame.
As the heat increases, the water vaporises increasing the pressure. This forces the
water through the receptacle holding the coffee grind, through the
filter and into the top part. Vala! espresso.
Although the theory of operation is relatively simple, using one of these things requires
unscrew the top part from the bottom part.
Put the correct amount of grind in the reciprocal, then tap it down (most instructions say
not to, but phooey to them).
Fill the bottom part with cold water up to the valve, BUT NOT OVER
IT. It is there so the thing doesn't explode if something goes wrong.
Reassemble the machine, and set the element or flame to high and place the machine on
Nothing much will happen for a few minutes, until all of a sudden you will hear gurgling.
Look into the top part and you will see dark coffee filling pouring from
the top of the tube in the middle. Wait until just less the desired amount of coffee as
flown in and take the machine off the heat.
Pour into a cup and drink immediately.
Before you run off, buy and operate a stove top espresso, a few safety tips:
Make sure the valve is not impaired, if it is, throw the machine away. Seriously, there is a
lot of pressure in these babies and the valve is there to stop it exploding.
Don't clean and reuse it until it has cooled down. This will take a while
The last one is really for the machine's safety as opposed to yours, but don't let it boil
Albert Herring says: You don't need to thow a basic Moka Express away if the valve blows - you can just replace it. Ditto rubber rings, filter funnels, filter screens, handles and the plastic knob to lift up the lid.
Also you need to fill the coffee space *completely*, since otherwise the pressure will force the coffee to one side and let the hot water mostly pass through without contacting it.
sneff says: The single best thing I have ever done to improve stovetop espresso is to fill the bottom chamber with hot water, not cold. The reasoning is that the water will take less time to get to pressure (boiling) temperature, and results in less flavour/aroma loss as a result. Have a try - I'm sure you will be impressed.