What is the "espresso extraction" process?

The "espresso extraction" process refers to the method of brewing espresso by forcing hot water through finely-ground coffee under pressure. This technique is unique to espresso and is fundamental in producing the rich, concentrated coffee beverage that characterizes it. During the extraction, the water interacts with the coffee grounds, extracting the oils, flavors, and aromas that give espresso its distinct taste and creamy texture. The high pressure also leads to the creation of a layer of crema on top of the espresso, which is a hallmark of a well-extracted shot.

The other methods listed, such as soaking coffee grounds in water, brewing with a filter, or integrating coffee with milk and flavors, do not reflect the specific characteristics of espresso extraction, which is defined primarily by the pressure applied during the brewing process and the grind size of the coffee used.