Espresso ( Austro roasters ) is a native of Milan Kaffeezubereitungsart is pressed in the hot water at high pressure through very finely ground coffee made ​​from dark roasted coffee beans.

The procedure yields a concentrated coffee on which a dense hazel foam layer - the crema - is that contributes to its flavor . Due to the strong roast and a typical serving size of 25 ml of the caffeine content of a cup of espresso in total , although low in concentration but higher than that of a cup of filter coffee (typically 125 ml). Espresso is usually served in small, thick-walled and pre-warmed cups with about 40 ml capacity and sweetened or unsweetened drink . It is often served with a glass of water.

Espresso is now the most common way of preparation for coffee in southern Europe , particularly in Italy , Spain, Portugal (where it simply café is, in Lisbon bica sl ) and France (where it is called expresso or petit noir ) . In these countries obtained for tourists often surprising , an espresso, if you coffee ( Italian: caffè, French , Spanish: and Portuguese: café , gr : καφές , Bulg : kaфe , Croat . Kava ​​) ordered. In Switzerland, espresso is usually prepared in German Switzerland as the most common espresso lungo (German : café crème or just coffee) , in western Switzerland as a normal espresso [ 1].

Ultimately depends on the quality of an espresso not only on the mixing ratio. For the preparation of a good espresso are traditionally five criteria be met ( the 5 -M - formula [4 ] ) :

The mixture - the selection of the coffee beans ,
Quality of the beans
Careful and appropriate to the beans roasting
Freshness of the beans used
The amount - the right amount of powder (usually 7 g) ,
The grind - the right , not too coarse , not too fine grinding of beans,
The machine - a good machine ,
Temperature of the water
Pressure of the water
Quality (including hardness ) of the water
The man - the maker of the drink.
Soulful Tampern according to the degree of grinding ( = pressing of coffee grounds into the filter )
Properly chosen ( thick-walled and preheated ) cup, because the espresso cools fast otherwise
Coordination of all factors to each

A simple to carry out quality test is the so-called " island test ": When sprinkling of sugar in the espresso itself must form only gradually goes down a " Sugar Island " . This is not the case, the coffee has a little cream or crema to low consistency . In general, an espresso , which is the island sample , obtained only from traditional espresso coffee machines , are therefore rarely used in Italy fully automatic .

Also important for the quality of the pressing, the pressing of the ground coffee in the filter holder by means of a plunger-like " coffee tamper " ( Pressino ) . About the pressure there are different opinions : While many experts a pressure of 20 kg as the optimal and thus considered setpoint is , in many Italian bars, the coffee is only lightly pressed . So that the processing time in the above-mentioned approximate 25 seconds is , however, the grind needs to be coarsened at greater pressure , more finely adjusted with less pressure.
Typical amounts , temperatures, pressures, etc. [edit ]

The Istituto Nazionale Espresso Italiano (German : National Institute of Italian Espresso ) has established the following criteria: [6 ]

necessary amount of ground coffee = 7 g ± 0,5 g
Water temperature at the outlet of the unit = 88 ° C ± 2 ° C
Beverage temperature in the cup = 67 ° C ± 3 ° C
Pressure water input = 9 bar ± 1 bar [5 ]
Cycle time = 25 seconds ± 2.5 seconds
Viscosity at 45 ° C> 1.5 mPa s
Total fats > 2 mg / ml
Caffeine <100 mg / cup
Volume in the cup (including crema ) = 25 ml ± 2,5 ml

A laboratory is the ideal preparation to as :

Amount of coffee beans : 6.95 g
Water temperature: 92 ° C
Pressure water input: 9.3 bar
Cycle time: 25 seconds

Source: Wikipedia