Espresso is essentially a concentrated coffee drink extracted by an Espresso machine under tremendous pressure, creating a layer of foam (Crema) on the surface. Espresso has a thicker consistency than coffee prepared by other methods. It has a higher concentration of suspended solids, dissolved substances, and Crema.

The Specialty Coffee Association (SCA) defines Espresso coffee as:
“… A 25-35ml beverage is made from 7 to 9 grams of coffee (14 to 18 grams for Double shot ); Accordingly, hot water from 90.5 – 96.1 o C is pressed at a pressure of 9 – 10 atm through ground coffee so that the brewing time is 20-30 seconds. While brewing, the Espresso line will have the viscosity of warm honey and the resulting coffee will have a thick, dark yellow crema. Espresso should be prepared and served immediately to the consumer.”
However, also according to a survey by SCA, the concept of Espresso is not a standard. A cup of Espresso coffee 36.5 grams starts with a dosage of 18 – 20 grams (using basket18 grams), extracted in 25 – 30 seconds, with hot water 93°C, at a pressure of 9 bar, which is popular in the world. most modern coffee shops
Origin of Espresso
Espresso coffee originated in Italy, and the invention of the first espresso machine was recorded by Angelo Moriondo from Turin, Italy, in 1884 (according to the Smithsonian ) with the name “instantaneous confection of coffee beverage.” The initial prototype was not famous until 1903 when Luigi Bezzera made a few improvements over the original and invented the Espresso newly called Crema Caffè, due to the presence for the first time the class Crema together. Espresso eventually replaced the term.
There is some confusion surrounding the correct spelling of this noun. The most common spelling is ” Espresso, “although ” Expresso ” is an accepted variant.