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Espresso types

Types of espresso (click to enlarge)

Espresso is the name of a highly concentrated, bittersweet coffee originating in Italy in the early 20th century. Translated from Italian, the word espresso refers to the speed and single-serve nature of the coffee compared with slower and more communal methods of brewing coffee[1]. Each shot of espresso is made to order upon customer request, as opposed to being brewed in anticipation of demand. Typically served in a demitasse cup or used with other ingredients to create another beverage such as a cappuccino or a caffè corretto, espresso has become representative of coffee culture in many coffee-consuming regions.

Characteristics[]

While the taste of espresso will vary widely depending on the coffee (including the roast), the quality of grind, and technique used to brew it, a well-made espresso will generally have a heavy body, rich texture, and a bittersweet taste. Each shot should have a layer of crema (foam) on the surface, generally golden to dark tan in color. A single shot of espresso is generally made with seven to eight grams of ground coffee and results in between one to one and a half ounces of coffee. This ratio represents a highly concentrated coffee, containing more caffeine per volume and generally considered to be stronger than drip brewed coffee.

Making Espresso[]

There are several types of espresso-based beverages, but all are based on one or more shots of pure espresso. Espresso is brewed in some sort of espresso machine which "presses" hot water through a dense puck of finely ground medium to dark roasted coffee.

Espresso-0

Preheat your cups, it makes a big difference, particularly if you drink doubles or if you're making for several people. By the time you hit the bottom of your cup, or finished making the coffee for the last person, the first shot can be very cold. Boiling water usually makes the cups too hot to hold, but filling them with hot water from the tap works well. If you put hot tap water in your cups before starting to brew coffee they will be ready by the time you get everything ready. You will also want to warm the brew head before starting. If you do not do this the heat of the water will be dissipated by warming the brew head. If you are making multiple cups leaving the brew head in the machine between cups should keep it warm.

Make sure the coffee is ground for an espresso machine. If the coffee is too coarse the water will go through too fast and will not extract the nectar from the coffee. If the coffee is ground too fine the water will not be able to travel through the grounds properly and may lead to over extraction. Think of salt as a general rule. The best, of course, is to grind your own, but you can tell your coffee supplier to grind for an espresso machine. Until you get the knack of exactly how fine is fine enough you might want to buy pre-ground coffee to get an idea of what is correct. Espresso is definitely one place that a whirly blade grinder will not work.

Make sure the filter basket is full, and tamped correctly. This is another one of those places that a little experimentations is in order. If the coffee is tamped too hard water will not flow through. If it is not tamped hard enough the water will run through the grounds too quickly. Every machine is a little different. Experimentation is the key. So be sure that the coffee is level. If it is not you will be providing a path of least resistance for the water to go through.

Turn off the machine or move the cup away as soon as you see the streams of coffee coming out of the machine have become thin. If you keep going after this point, you're just pumping bitter over extracted garbage into your cup. The more you run out, the worse it will taste (more information on this method). If you want a longer drink, make a double, or add hot water to your espresso (an Americano).

Espresso should be served immediately. Ideally, the crema on an espresso should be all one color and preferably a very light honey color. If the crema has dark streaks, then the beans you have may have been burnt too much in the roasting process. Alternatively, the temperature on the machine itself could be set too high, and the coffee's being burnt by the water there. If there's uneven crema, then either the coffee has been left sitting too long after being ground, or the dose in the handle hasn't been tamped down firmly enough.

History[]

Kaffeemaschine

An early style of espresso machine.

The rise of espresso as a popular coffee has paralleled technological advances to the espresso machine during the 20th century. Still, earlier forms of coffee brewing gave rise to the modern espresso. Much like espresso, coffee brewed in an Ibrik (or related brewer) was dark roasted, unfiltered, thick, and bittersweet. Additionally, when brewed correctly, this coffee has a layer of foam much like the crema of espresso. Traditionally served strong and sweet, coffee in the Middle East and Southeastern Europe was a natural step toward the technicalogical developments which would give rise to modern espresso[2].

In 1901, Luigi Bezzera patented what is considered to be the design for the first espresso machine. It was based on the principle of earlier coffee makers (similar to a moka pot) which used steam pressure to push water into an area from which it would be pressed by the force of gravity through the coffee and into a reservoir. Bezzera's system, however, would use the pressure from the steam to force the hot water directly through the coffee and into the cup. His design allowed for serving freshly brewed coffee to customers on demand. Bezzera would sell this patent to Desiderio Pavoni, who, in 1905, would begin manufacturing the espresso machines for sale. Other Italian manufactures would soon follow suit[3].

Early espresso machines were large and ornate, using gas as their heat source. They consisted of large, cylindrical reservoirs turned on their end, with several spouts, valves, and gauges protruding from the front and sides. Finally, the espresso machines were topped with an ornate figurehead, most often an eagle[4].

These early machines were limited to the amount of pressure that could be produced by the steam alone--around one and a half atmospheres (meaning one and half times the pressure exerted by the earth's atmosphere), not high enough to allow for full extraction of the coffee oils or use a heavily packed puck of coffee. Higher steam pressure could be generated from using more heat, but the hotter water caused the coffee grounds to become overheated as well, damaging the taste of the resulting cup.

In 1947, Achille Gaggia developed a modification to espresso machines which, instead of using steam pressure to drive the water through the coffee, used a manually pulled lever to cause a piston to press the hot water through the coffee. The higher pressure generated through this method allowed for a much tighter packed puck of coffee and a more full extraction of the coffee's flavors. Additionally, through this method, the signature crema that floats at the top of a properly prepared espresso was first born[5]. Despite continuing improvements, modern espresso makers are still mostly based upon Gaggia's model[6].

One of the drawbacks to the Gaggia machine was that both the water for the espresso and the steam were heated in the same tank. The water would heat slowly, and would become stale over time, affecting the quality of the resulting espresso. In 1961, the FAEMA company (Fabbrica Apparecchiature Elettromeccaniche e Affini or, in English, factory producing electrical and mechanical equipment and similar) developed the E61, a machine which would heat water for use in brewing the espresso by passing it through the tank of older water before it got to the brew head. The fresh water would never interact with the older water, which would be reserved for use only in the production of steam. Other improvements in the E61 included an electric-driven pump, a mechanism for decalcifying water (so as to not to contaminate the machine with deposits), and the ability to circulate water through the group head so that it would reach a warm temperature prior to brewing without having to run water through it first[7].

References[]

  1. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 3. ISBN 0312246668.
  2. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 11-12. ISBN 0312246668.
  3. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 16. ISBN 0312246668.
  4. Kenneth Davids (2001). Coffee: A Guide to Buying, Brewing & Enjoying, Fifth Edition, 148. ISBN 031224665X.
  5. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 17-19. ISBN 0312246668.
  6. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 17-19. ISBN 0312246668.
  7. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 20-21. ISBN 0312246668.
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