What is an espresso?
An espresso is an Italian coffee specialty called caffè espresso.
How do you make espresso?
An espresso is prepared with water at 89 +/- 5 degrees Celsius, which is pressed through the finely ground coffee in just 30 +/- 5 seconds at 9 bar pressure. The typical volume of an espresso is 25 to milliliters.
Latin expresso means to express. When making espresso, hot water is forced through the coffee. This used to be done by hand, with a hand lever. Such espresso machines still exist today.
Hand lever espresso machine
Hand levers are the original espresso machines. A steel spring is tensioned with the lever. The piston then pushes the hot water through the coffee at 9 bar.
With a hand lever espresso machine, both the bitterness and the acidity become slightly less strong. The hand lever espresso machine was invented in 1938 by the Milanese Giovanni Achille Gaggia invented.
The special thing is that making coffee in this way only takes a few moments and the typical process is created by extracting the coffee under pressure Crema.
The hand lever espresso machine has been replaced by espresso machines that produce the required pressure using an electric pump. A hand lever espresso machine does not require electricity. The water can be heated with gas and the espresso can be tapped by hand.