Espresso
Espresso is a concentrated coffee brewing method that forces hot water through a tightly packed bed of finely ground coffee at approximately 9 bars of pressure. The result is a small, intense shot — typically 25 to 35 milliliters — topped with a layer of golden crema formed by emulsified oils and CO2 released from freshly roasted beans.
What distinguishes espresso from other methods is the combination of pressure, fine grind, and short contact time. A well-pulled shot extracts in 25 to 30 seconds, dissolving sugars, acids, and aromatic compounds in a balanced ratio. The high pressure also creates the syrupy body and crema that cannot be achieved through gravity-fed brewing.
Making espresso requires an espresso machine with a pump or lever mechanism, a portafilter, and a grinder capable of producing a consistently fine grind. Variables that affect shot quality include dose (the weight of dry coffee, usually 18–20 grams for a double), yield (the weight of liquid espresso, typically 36–40 grams), brew temperature (usually 195–204°F), and pre-infusion time.
Espresso serves as the foundation for milk-based café drinks including lattes, cappuccinos, flat whites, and macchiatos. It can also be enjoyed straight as a single or double shot, or diluted with hot water to make an americano. The pursuit of the perfect espresso shot is often described as equal parts science and craft.