Lungo

Lungo (Italian for "long") is a coffee beverage made by using an espresso machine to make an Italian-style coffee – short black (single or double dose or shot) with much more water (generally twice as much), resulting in a larger coffee, a lungo.

A normal serving of espresso takes from 18 to 30 seconds to pull, and fills 25 to 60 millilitres, while a lungo may take up to a minute to pull, and might fill 130 to 170 millilitres. Extraction time of the dose is determined by the variety of coffee beans (usually a blend of Arabica and Robusta), their grind and the pressure of the machine. The optimum is obtained with 9–12 bars 130–150 ml.

In French it is called café allongé.

A caffè lungo should not be mistaken for a caffè americano, which is an espresso with hot water added to it, or a long black, which is hot water with a short black added to it (inverse order to Americano; done so to preserve the crema).

In the lungo, all the water is brewed, and the lungo is generally shorter than an Americano or a long black.

A significantly longer drink, comparable in size to an Americano or long black, rare in the English-speaking world, is the caffè crema, which, like the lungo, is all brewed water, but is about twice as long as a lungo.

A lungo is less strong, but more bitter, than an espresso, because the additional hot water passing through the ground coffee extracts components that would normally remain undissolved. The more water is passed through the coffee grounds, the more bitter and watery the shot tastes. Conversely, using less water than normal produces a stronger, richer shot known as a ristretto.

As the amount of water is increased or decreased relative to a normal shot, the composition of the shot changes due to the fact that the flavour components of coffee dissolve at varying rates. For this reason, a long or short shot will not contain the same ratio of components that a normal shot contains. Therefore, a ristretto is not simply twice as "strong" as a regular shot, nor is a lungo simply half the strength. Moreover, since espresso is brewed under pressure, a lungo does not have the same taste or composition as coffee produced by other methods, even when made with the same ratio of water and ground coffee.

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Wikipedia