One of the most common ways to roast coffee beans is by roasting the beans in a drum. Not a drum that you would find in a band, but a drum specifically made for roasting coffee.
In this type of roasting, coffee beans are placed in a cylinder-shaped chamber, known as a drum. As the drum spins, with the coffee beans inside, the coffee beans are evenly roasted. Using either an open flame underneath, gas, electricity, or wood, the beans become roasted on all sides. By turning the drum consistently, this ensures that all the coffee beans get roasted without having some roasted more than others.
WHAT DOES COFFEE ROASTING MEAN?
Since coffee beans cannot be consumed in their raw form, they need to be chemically and physically broken down before they are distributed to producers, a process known as coffee roasting. There are many different methods to roast coffee beans, (with drum roasting and hot-air roasting being the most common) and many different levels of roasted coffee as well (light, medium, and dark). The roasting process is what gives the coffee its bold and robust flavor.
Depending on the roasting method that was used, the flavor of the coffee can be altered drastically. For mild coffee, a light roast coffee should be used, whereas for strong coffee a dark roast should be used. Not only does coffee roasting change the flavor of the coffee, but it also changes the acidity, aroma, taste, and caffeine levels of the coffee. If you are unsure which type of roasted coffee is best for you, start with a light roast and make your way up if you find that it isn’t strong enough.
WHAT DOES A DRUM ROASTER DO FOR YOUR COFFEE?
The drum roaster is a way to turn the original coffee beans, from their green-like shell to the coffee beans we all know and love. This method helps bring the beans to their natural potent form, leaving the raw material behind.
The cylinder that is used for a drum roaster is placed horizontally so that the coffee beans can rotate easily and roast all around. In most cases of a drum roaster, the flame (or heat) is placed underneath the chamber so that it can roast the beans as they tumble over it. Very rarely will a drum roaster use a direct-fire roaster to roast the beans. A direct-fire roaster is where the flame comes in contact with the coffee beans themselves since it is placed inside the chamber itself. Being directly in the chamber allows the flame to roast the coffee beans almost immediately.