Frequent Asked Questions about Coffee:
What Is Espresso?
Espresso Coffee: Espresso (Italian) is a concentrated coffee beverage brewed by forcing very hot, but not boiling, water under high pressure through coffee that has been ground to a consistency between extremely fine and powder.
It was invented and has undergone development in Milan, Italy, since the beginning of the 20th century, but up until the mid 1940s it was a beverage produced solely with steam pressure. The invention of the spring piston lever machine and its subsequent commercial success changed espresso into the beverage we know today, produced with between 9 and 10 atmospheres, or Bars, of pressure.
The qualitative definition of espresso includes a thicker consistency than drip coffee, a higher amount of dissolved solids than drip coffee per relative volume, and a serving size that is usually measured in shots, which is about 1 - 2 ounces in size. Espresso is chemically complex and volatile, with many of its chemical components degrading from oxidation or loss of temperature. Properly brewed espresso has three major parts: the heart, body and, the most distinguishing factor, the presence of crema, which is a reddish-brown foam which floats on the surface of the espresso. It is composed of vegetable oils, proteins and sugars. Crema has elements of both emulsion and foam colloid.
As a result of the high-pressure brewing process, all of the flavors and chemicals in a typical cup of coffee are concentrated. Some people prefer a single or double shot of espresso instead of one or two cups of coffee to get a quick shot of caffeine. Because of its intense and highly concentrated ingredients (including caffeine) espresso lends itself to mixing into other coffee based drinks, such as lattes, cappuccini, macchiati and mochas, without being overly diluted in the resulting drink.
