Brewing Coffee

Coffee is brewed by exposing ground coffee to hot water. The hot water dissolves from the ground coffee the substances that give coffee its characteristic flavor, aroma, and color. The matter that remains—the grounds—is usually discarded.

Coffee can be brewed simply by boiling or steeping ground coffee in water. However, when made in this way, coffee tends to be stronger and more bitter than when the brewed coffee is kept separate from the grounds. In the United States, coffee is commonly brewed by the drip method. Typically, the ground beans are placed in a paper filter fitted into a receptacle with a hole at the bottom. Boiling water is poured onto the ground beans and coffee drips into a container below. In percolating, another common method, the ground coffee is put in a perforated basket at the top of a container in which water is heated. As the water boils, it bubbles upward through a hollow tube and then trickles back down through the ground coffee. As the process continues, the coffee in the container gradually becomes stronger.

A very thick, sweet coffee, called Turkish coffee, is made by bringing to a boil a mixture of water, sugar, and very finely ground coffee beans. Espresso is a strong coffee made by exposing ground, highly roasted coffee to steam. Cappuccino is an espresso coffee to which frothy cream or frothy milk has been added. Coffee is sometimes flavored with chicory, cinnamon, vanilla, chocolate, almond, or other additives.