The Coffee Roasting Process

Have you ever wondered how your morning cup of coffee gets its wonderful flavor and aroma? For a coffee bean to go from green to brown, it first must go through the roasting process. The roasting process is the most important step in creating a quality coffee product. It takes a skilled roaster to bring out the best of flavor and aroma in the coffee bean.

There are no universal standards in coffee roasting. This is because roasters develop their own personal blend and roast combinations. There are light roasted to extremely dark roasted blends to meet the diverse tastes in coffee drinker preferences. A city roast is a dark roast, while a full city roast is slightly darker yet. A French roast is roasted until natural oil appears on the surface of the bean. An Italian roast is roasted until carbonized to allow it to be easily powdered.

A standard roasting method involves placing the beans in a vertical or horizontal rotating drum or cylinder. The beans are then baked at 450 degrees Celsius by hot gasses for eight to twelve minutes, depending on the roast.

During roasting, the coffee bean changes both physically and chemically. After it has been roasted for a short time the bean turns a yellowish brown color and then gradually darkens as it is roasted longer. As the coffee beans heat up, they shrivel up until reaching the halfway point in the roasting process. This halfway point is called the “developing” point. In this stage the beans begin to swell up again and pop open, which is called the ‘first pop’ or ‘first crack’. This increases their size by about fifty percent. At the developing point the heat is increased and roasting is completed as quickly as possible, usually until or just before the ‘second crack’ which occurs at a higher temperature. When the coffee reaches just the right level of roasting, the heat is turned off to stop the roasting and the temperature of the coffee beans is lowered as quickly as possible.

The cooling down of the beans is done with either a wet roast method of a dry roast method. In the wet roasting method the coffee is sprayed with water in the roasting cylinder to cool the beans and stop the roasting process. In the dry roasting method the beans are taken out of the roasting cylinder and put in a strainer basket where they are stirred while air blows through the beans to cool them as quickly as possible.

After the freshly roasted beans have cooled they are packaged. The packaging machine will remove all oxygen from the bag and replace it with nitrogen. The bag is then heat sealed to maintain freshness.

Roasting coffee to perfection takes a special skill. When you stop and think about everything that has gone in to your morning cup of coffee it will make you really want to savor all that wonderful aroma and flavor and appreciate the art of coffee roasting.