Our roasting community here in Denmark is exploring a new approach on the Bullet R1 roaster.
15 of us were on a roasting course with Michael de Renouard from The Factory Roast Lab Copenhagen. He is a roasting consultant and travels the world teaching coffee roasting. In his own roastery he is roasting on a Loring. He roast quite light.
Michael tried out the Bullet roaster. He thought it did well; no burned or smoked taste in the beans. And its possible to get the beans heated quickly. He likes that you can control heat and airflow separately.
He found that you could start out with high heat without the beans got scorched/burned. Preheat 200°C for a 700 grams batch and then P8 – leaving room to step up to P9 at then end of the ROR peak.
But this was for high density beans (high grown). Be aware that lower density beans, like brasil, need a lower preheat temperature. Steffen got a Costa Rica bean which gets burned if the preheat is more than 170°C.
The high heat makes a fast start on the roast. But if it doesn’t scorch the beans, then no problem. Michael focus on the lenght of the phase from yellow until First Crack start. Here he aims at 3 minutes and at the same time aim to bring ROR below 5 for the First Crack phase. To do this the heat must be turned down markedly.
Exploring the difference
Here Thomas Villars used the strategy on a etiopean bean. He thought it tasted better than earlier roasts of the same bean. Despite FC starts as early as 5:23 min.
In general a fast roast like this gives more “clarity” in the taste – and less body. Here the “middle phase” – from yellow to FC start – is 2:15 minutes long. It should give more body to prolong this phase.
Earlier Thomas roasted the same bean like this:
Update 2 months later:
Thomas has continued this new strategy. He like his coffees better now.
There are many approaches in coffee roasting. Don’t take this website as the only way to do it. Just take it as inspiration – and explore for your self what suits your taste.