Espresso is an Italian tradition of coffee brewing, traced back to the early 20th century in Milan. Espresso is Italian for express and refers to the coffee being drunk quickly.
In 1901, Luigi Bezzera patented a machine where steam pressure pressed water through grinded coffee. In 1903, the patent was sold to Desidero Pavoni, which, as the first, put the idea into production, starting a tradition that would later become a cornerstone of Italian bark culture - the (La Pavoni espresso machines).
The grinded coffee is stamped and maintained between two filters and 90 degrees hot water pressed with 9 bars pressure through the coffee. It is important that the coffee is grinded well and stamped, so that a suitable back pressure occurs so that the run-through time is about 25 sec. and the amount of coffee in the cup will be approx. 25 ml.
Traditional Italian espresso coffee is typically a mixture of up to 7 different kinds of raw-coffee.
Robusta is about 10% in the vast majority of mixtures as this is cheaper and additionally provides crema.
Many believe that Italian coffee is something particularly refined, but the truth is that Italy, statistically speaking, belongs among the countries that import the cheapest qualities in Europe.
This is in part a result of great competition among Italian coffee shops, but must also be seen in the light of the traditional Italian brewing method. It is the most volatile flavors that are the best. That is, it's the first drops that are pulled out of the coffee that are the best.
As a classic espresso is very small and concentrated and is consumed with large amounts of sugar, there are not as much demands on high quality as with e.g. Danish coffee. Most people only have good coffee experiences from Italy, which is due to the more detailed operation of the coffee machine (cleaning, setting of grinder, preheating of cups, etc.) than the actual coffee-quality.