For espresso, the coffee grounds are compressed into a dense “puck” of coffee, and hot water (about 195-200 degrees Fahrenheit, but not boiling) is forced through the puck under high pressure (between 9 and 15 bars), to produce an extraction which we call “espresso.” The extraction should take at least 25 seconds (to allow sufficient time for the water to be in contact with the coffee), but it should not take more than 30 seconds. The grind needs to be fine enough to create a dense puck so that the pressure can be maintained during the extraction. An espresso machine maintains the water at the right temperature, and controls the pressure and the duration of the extraction. This cannot be accomplished on the stove.

The resulting extraction, espresso, has a much more intense flavor than regular coffee. This is why espresso cups are tiny. The normal serving of espresso is about an ounce and a half – the same as a shot. A 2.5 ounce serving is called a double serving, or a doppio (which is Italian for “double”). Milk or cream is never poured into espresso (except when making other drinks, which are no longer called “espresso”), although espresso can be sweetened with sugar if desired.

Ristretto (also called a “corto”) is a very “short” shot of espresso coffee. Originally this meant pulling a hand press (shown at right) faster than usual using the same amount of water as a regular shot of espresso. Since the water came in contact with the grinds for a much shorter time the caffeine extracted in reduced ratio to the flavorful coffee oils. The resultant shot could be described as bolder, fuller, with more body and less bitterness. All of these flavors are usually attributed to espresso in general, but are more pronounced in ristretto. Because of this exaggerated flavor, ristretto is often preferred by espresso coffee lovers. Today, with the hand press out of favor and modern automated machines generally less controllable, ristretto usually just means less water; a normal (double) espresso shot is typically around 60 ml (2 fl oz), while a (double) ristretto is typically 45 ml (1–1.5 fl oz).

One modern method of “pulling” a ristretto shot is to grind the coffee finer than that used for normal espresso, and pull the shot for the same amount of time as a normal shot. The smaller spaces between the particles of finer-ground coffee allow less water to pass through, resulting in a shorter shot. However, this can also lead to a gritty taste, if the coffee is ground fine enough that the insoluble components can pass through the filter-basket. This is often a problem in poorer grinders, where the grind is not as even.

Another modern method for pulling a ristretto is to simply stop the extraction early, so less water has time to pass through the ground coffee. This produces a slightly different taste than the fine-grinding, equal-time method, and is often preferred because it does not require the barista to change the settings on the coffee grinder.

A third modern method, that serves as a compromise between the previous two, is to prepare the shot without adjusting the grind but to use the tamp more firmly. The firmer tamp will compact the grinds in the filter basket allowing for a shot time comparable to a regular espresso. This method has the added benefit that adjusting the coffee grinder is not necessary while keeping much of the body and flavor of the fine-grinding, equal-time method.

As the amount of water is increased or decreased relative to a normal shot, the composition of the shot changes, because not all components of coffee dissolve at the same rate. For this reason, an excessively 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 twice as weak.

I hope you like this… I am getting hooked on Espresso