When roasting coffee, carbon dioxide (CO2) naturally builds up within the beans. Allowing the beans to rest lets this CO2 escape, resulting in a balanced flavor. This is true for all roasting methods, but the rules around roasted coffee management change with air roasters. In drum roasting, latent energy builds up and reacts on the bean. Roasting techniques like decreasing Rate of Rise (ROR) and managing airflow and heat at specific stages are used to control this buildup and influence the coffee bean's development. The goal is to minimize conductivity and maximize convection energy application, ensuring the roast progresses at the right pace. However, with the latent energy buildup, this process becomes challenging. The introduction of air roasters, such as the Kaffelogic Nano7, changes this dynamic. With air roasting, the heated air surrounding the coffee in the chamber performs the roasting work. The roaster can adjust this heat and intensity through its fan, driving heat to develop flavor. The minimal latent energy buildup in air roasting provides a cleaner mouthfeel in the finished coffee. A key adaptation in air roasting is the ROR curve during the Maillard phase. A short delay between application and result allows for precise control of the ROR curve, affecting CO2 buildup and the coffee's development.

By manipulating how CO2 is released during the Maillard phase with minimal risk to flavor, the resting process can be sped up from days to hours. This is achieved by applying more aggressive heat early in the Maillard phase, followed by a dramatic adjustment of ROR points every 10 to 30 seconds. This step-like, negative-looking arc in the ROR curve creates a CO2 vacuum. Transition phases between sharp decreases and decreasing plateaus are crucial for flavor development. Too slow, and not enough body develops, leaving too much CO2 in the bean; too fast, and sugars over-caramelize, leading to bitterness with insufficient CO2 and flat coffee. Balancing this process allows for developing a roasting profile that can be ground and brewed immediately. The key is to enjoy the coffee experience and push roasting boundaries with taste as your guide. These RTD profiles were developed on the Kaffelogic Nano7 with a 120g roasting capacity and the Kaffelogic Studio roasting profile software.