Espresso & Cappuccino Machines

An espresso machine is used to produce the traditional Italian coffee beverage called espresso. more...

Generally, espresso is produced by forcing 90°C (200°F) water through 7-10 grams of finely ground coffee, which has been compressed with approximately 30 lbf (130 N) of force into a densely packed puck, at a pressure of 900 kPa (9 bars) or greater.

Types of espresso machines

Since their invention in 1901, multiple machine designs have been created to produce espresso. They generally share some common elements. The portafilter (or group handle) contains a metal filter-basket and holds the ground coffee. It is locked under the group head's diffusion block.

An ideal double shot of espresso should take 20-25 seconds to arrive, timed from when the machine's pump is first turned on. Varying the fineness of the grind, the amount of pressure used to tamp the grinds, or the pump pressure itself can be used to bring the extraction time into this ideal zone. Most prefer to pull espresso shots directly right into a pre-heated demitasse cup or shot glass, to maintain the ideal temperature of the espresso.

An espresso machine may also have a steam wand which is used to steam and froth milk for beverages such as the cappuccino and latte.

Steam-driven

A steam-driven unit operates by forcing water through the coffee by using steam or steam pressure. The first espresso machines were steam types, produced when a common boiler was piped to four group heads so that multiple types of coffee could be made at the same time. The design is still used today in low-cost consumer machines, as it does not need to contain moving parts.

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