- $5 for three Groupons, each good for $10 worth of cafe drinks (a $10 total value)
Espresso: Coffee Under Pressure
If mochas and lattes send your head spinning, then you can always boil it down to basics with a simple espresso shot. Groupon's study of the small but complex brew explains why the tiny cup packs a big flavor punch.
The espresso machine is the hulking, huffing beast of the coffee-shop counter, laboring loudly to produce a comically disproportionate product: a doll-sized serving of thick, reddish-brown liquid. It's this machine, more than the type of beans used or how they're roasted, that sets espresso apart from drip-brewed coffee. Espresso machines force pressurized water for 25–30 seconds through a tightly compacted heap of coffee ground to a powdery consistency, a process known as extraction. The resulting shot contains a high concentration of dark, robust flavors and is topped with a frothy layer known as crema. The latter isn’t quite what it sounds like: the attractive caramel-colored foam is created solely by the intense water pressure during the brewing process, no dairy needed.
In Italy, espresso's home turf, shots are often drunk quickly in three or four gulps or one long crazy-straw sip. Some Italians add sugar to their shot, although great espresso presents a bouquet of rich flavors all by itself. Espresso shots are also the essential building blocks of most other classic coffee-shop drinks, including the cappuccino (espresso with steamed and foamed milk) and the americano (espresso and crema poured over hot water).