Espresso is a concentrated beverage, 1 to 2 oz. shot of pressure-brewed coffee using between 6.5 and 7.5 grams (about 1 Tablespoon) of finely ground coffee. Brewing takes about 25 to 30 seconds. Properly brewed, an espresso will feature a layer of rich dark golden cream, called crema on the surface. This crema is one 

indictor of a quality espresso. Making a great espresso is truly an art as well as a science. As a result of the pressurized brewing process, the flavors and chemicals in a typical cup of espresso are very concentrated; so it is the base for other drinks.

Espresso is a coffee beverage and brewing method, it is not a specific bean, bean blend, or roast level. Drinking an Espresso Coffee can also be an art. In an Italian café, you might witness patrons breathing in the aroma as they hold the cup and saucer, and then drinking the entire beverage in 3 or 4 quick gulps. The ritual is finished by firmly but gently tapping the cup back onto the saucer. Adding sugar to the espresso is an accepted practice in Italy, and there is no shame in adding sugar to your beverage. But a truly great espresso is a joy to drink without any additives. You can then taste and appreciate the essence of the espresso more completely.

Any bean or roasting level can be used to produce authentic espresso. For example, in southern Italy, a darker roast is generally preferred; but farther north, the trend moves toward slightly lighter roasts. Outside of Italy a wide range of roasts are popular

 

Light or Full City Roast - A light or full city roast is achieved when the natural sugars have caramelized. The beans have a rich brown color. 

Medium or Vienna Roast - At this point the natural sugars in the bean have begun to burn. They are just at the edge of darkness. The oils in the beans are just beginning to surface and the beans are a darker brown than light roast. This level of roasting produces a very full, rich flavor          

French Roast - Once the natural sugars are burning, we have a French roast. The coffee oils have come to the surface and the beans are dark brown. With this roast the character of the burning sugars starts to compete with the regional character.   

Italian Roast - We've burnt the sugars here! The result is a very dark brown oily bean. The bittersweet flavor is a result of the dark roast.