Coffee is brown or black before drinking, but this is because the green beans are roasted and then burnt.
This process of roasting the beans is called roasting, and the roasting process affects the coffee's taste.
Some coffee shops and cafes roast their own beans, while others purchase them from roasters.
Mass-production roasters are capable of roasting over 100 kg in a single roast.
Most roasters use drum-type roasters, either city gas or propane.
Drum-type roasters come in three types: (1) direct-under type, (2) hot air type, and (3) semi-hot air type.