What is what in the world of espresso coffee...
A professional espresso machine operator.
The part of the espresso machine where the grouphead, portafilter and filter baskets are located.
Crema is a thick layer of aromatic, reddish brown foam which results from passing hot water under pressure through finely ground coffee. It consists mostly of carbon dioxide that has been liberated from the plant fibers.
To some extent the presence of crema is a gauge as to the quality of an espresso machine. Steam-based espresso machines won't produce much of a crema, if any. Espresso without the crema is just strong coffee.
The part of the brew group which dispenses water into the portafilter and filter basket.
Espresso, often mistakenly pronounced or spelled as "expresso", is simply another method of brewing coffee.
It is made by extracting the best parts of the coffee, using water which is not quite boiling and under intense pressure. This brewing process is timed so that the aromatic oils are extracted from the coffee and not the bitter components. The result is a full-flavored, strong but not bitter, concentrated shot of coffee.
There are many variables in the process of making a shot of espresso, including the water temperature, water pressure, the fineness of the ground coffee and how tightly the coffee is packed.
A metal sieve that fits inside the portafilter to hold the ground coffee.
The part of the brew group that contains the connector for the portafilter and the dispersion screen.
Over-extracted espresso results from exposing the coffee grounds to the brewing water for too long. It often tastes either burnt or bitter.
The portafilter is the removable "handle" that holds the filter basket containing the ground coffee. On better quality espresso machines they are made of chrome-plated copper or brass.
The coffee grounds that remain after brewing a shot of espresso.
The act of producing a shot of espresso is known as pulling a shot. It comes from the time when espresso was prepared by pulling a lever on an espresso machine.
Tamp or tamping is the act of compacting the ground coffee after it has been put into the filter basket. To produce consistently excellent shots of espresso, ground coffee should be evenly tamped at 30 lbs of pressure.
The device used to tamp (compact) the ground coffee.
Under-extracted espresso results from not exposing the coffee grounds to enough brewing water. This is often due to overly coarse coffee grounds, uneven tamp or insufficient tamp pressure. The resulting espresso tends to taste weak and thin-bodied.
The tank or container that holds water used by the machine to brew espresso and produce steam.