All About the Classic Drum Roaster
Coffee roasting is basically the process of breaking down green coffee beans physically and chemically, using heat, resulting in the bold, robust flavors that we all know and love. Different roasting methods will have different impacts on how the roasted coffee beans develop and the final taste that you get in your cup. The two main roasting methods used to transform coffee beans are the drum roasting method and the hot air method. In this blog, we will focus on the classic drum roaster, what coffee characteristics we can expect to get from a drum roaster, the pros and cons, and tips on how to choose the right drum roaster for your business.
What Happens When Coffee Beans Are Roasted?
The coffee roasting process is complex and involves a lot of changes. The green coffee beans change to pale yellow and then darken to brown when the Maillard reaction takes place. At this point, the reduced sugar and amino acids react to form aroma and flavor, transforming the bitter, rock-hard seed into virtually everyone’s favorite beverage.
As the roasting progresses, moisture inside the beans evaporates, causing an outwards explosion from the energy buildup known as the First Crack. From this point, the beans double in size but lose up to 20% of their weight as they shed a layer of skin called Chaff. Past the first crack, the roasting process continues to develop a variety of flavors and taste notes depending on how far the coffee roaster wants to take them.
Roasting Coffee Using a Classic Drum Roaster
In this method, the green coffee beans are put in a cylinder-shaped compartment known in the industry as a drum. Once the beans are placed inside, the drum rotates so they are evenly spaced and roasted above an open flame, fired by wood, or powered by gas or electricity. This method ensures that each coffee bean has an equal and even chance of getting roasted.
Classic drum roasters are also equipped with a fan that pulls hot air from the burner through the drum and out of the roaster. In addition, professional roasters can alter and manipulate many elements of the roast, such as drum speed, air speed, and heat application to experiment with each stage of the roast.
To understand the heat transfer inside a coffee roaster machine, read more here.
The Pros and Cons of A Drum Roaster
Drum roasting will always hold a soft spot for traditionalists. It roasts more gradually like a DIY manual method, with the roast time ranging from 10 to 20 minutes. For this reason, it offers great control over the time, temperature, and roasting profiles. Drum roasters tend to develop the body of a coffee while maintaining brightness. They are also known to be more affordable and durable than hot air roasters, due to their minimal need for the high-capacity fans that are typically required in hot air roasters. They are usually easy to maintain and replacement parts are readily available from the manufacturer.
Tips On Choosing The Right Drum Roaster
A classic drum roaster offers the opportunity for coffee roasters to create a unique flavor profile and get the most out of their coffee beans.
Since coffee roasting is ultimately the transfer of heat over time when choosing a classic drum roaster for your coffee business, it’s also important to opt for one with a burner that provides sufficient heat, and a double-walled drum to prevent excessive direct contact between the beans and fire.
Coffee roasters who wish to obtain a superior quality usually choose drum roasters that offer the versatility to play around with drum speed and airflow.
Berto Roaster machine offers smart drum roaster machines with all the right features designed for you to control, manipulate, experiment, and maintain your desired roast profile. From the compact-sized Berto Essential to the medium-sized Berto Type D-Roaster, achieving consistent quality has never been this easy. Berto Roaster elevates the classic drum roaster and brings it to great new heights, so your business can grow too. The sky’s the limit!