There are three major steps needed to prepare the green coffee beans for consumption.

Roasting:

Coffee roasting is a chemical process by which aromatics, acids, and other flavor components are either created, balanced, or altered in a way that should augment the flavor, acidity, aftertaste and body of the coffee as desired by the roaster.

The first stage is endothermic. The green beans are slowly dried to a yellowish color and it will give out a toasty aroma like popcorn.

The second step, often called the first crack, occurs at approximately 205 °C (400 °F) in which the bean doubles in size, becomes a light brown color, and experiences a weight loss of approximately 5%.

In the next step the temperature rises from 205 °C to approximately 220 °C, the color changes from light brown to medium brown, and a weight loss of approximately 13% occurs. The resulting chemical process is called pyrolysis and is characterized by a change in the chemical composition of the bean as well as a release of CO2.

Grinding

For proper extraction, it is essential to grind coffee properly. Grinding the freshly roasted beans before brewing is one of the most important steps for achieving a quality cup of coffee. Coffee should not be ground more than 2 minutes before brewing or major staling (oxidation) begins to take place.

Brewing

Brewing coffee is as much of an art as it is a science. Coffee should be brewed for 4.5-5 minutes using a ratio of 55 grams of ground coffee per liter of filtered water (195-205°F). It is convenient to use 2 tablespoons of coffee per 6 ounces of filtered water. Filtered water and spring water are recommended. Tap water imparts off flavors to the coffee and some minerals are essential to coffee flavor. Distilled water is not recommended for brewing coffee as it lacks the minerals to bring out the natural flavors of the coffee.