What is air roasted coffee? And why do we use this method when roasting our coffee beans?
When we talk about air roasted coffee we are referring to the method by which the coffee beans have been prepared. The other, more traditional, way of roasting coffee beans involves a drum roaster. A drum roaster essentially works like a large enclosed roasting tray, continuously rotating the coffee to prevent it from burning.
The coffee is roasted by contact with the surface of the metal drum, thus it is essential to keep the drum rotating to prevent it from burning. This is where the main issue with drum roasting comes in – it is a common occurrence with drum roasted coffee that the beans are over roasted, producing an inconsistent blend and a bitter tasting coffee. This being said, there is an artistry to drum roasting and when done correctly it can produce fantastic tasting coffee. A skilled coffee roaster is so in tune with their drum roaster that burning of the coffee should in reality rarely happen.
Air roasting, on the other hand, as the name suggests, uses currents of hot air to evenly roast the coffee. Often, the air roasting method is also called ‘fluid bed roasting’ as the machine used to air roast the coffee is called a fluid bed roaster. Fluid bed roasting has nothing to do with liquid, it simply refers to the way in which the coffee is roasted – the beans remain ‘fluid’ within the machine by being constantly rotated by currents of hot air introduced underneath the coffee. By keeping the beans levitating on a fluidized bed of hot air, the beans keep moving, preventing them from scorching on the hot surfaces of the roasting machine. The constant movement of the coffee and hot air roasts the coffee evenly and allows for very precise roasting of the coffee.
Developed by engineer and coffee industry consultant Michael Sivetz in the early 1970’s, he believed this method of roasting offered several advantages over the traditional cylinder roasting. He was later approached by German firm Neo-Tech, who continue to produce many of the world’s top fluid bed roasting machines today.
View our range of air roasted coffee beans here.