The Three Phases of Roasting (and Why We Stretch the Middle One)

Every roast, on every machine, in every roastery on earth moves through the same three phases. Where roasters differ — where the house style lives — is in how long they linger in each one. Here's the map, and then our favorite detour.

Phase one: drying

Green coffee arrives with around 11% moisture locked in its cells, and none of the fun chemistry can start until that water steams off. For the first several minutes the bean just absorbs energy — color barely changes, nothing smells like coffee yet. Rush this phase with too much heat and you scorch the outside while the inside stays raw; drag it out and the bean's energy fizzles before the flavors build.

Phase two: Maillard

Once the bean dries and passes roughly 300°F, the Maillard reaction begins — amino acids and sugars colliding into hundreds of new aromatic compounds. It's the same chemistry that browns bread crust and seared steak, and in coffee it builds sweetness, body, and complexity. The bean turns yellow, then tan, then cinnamon, and the roastery starts smelling like baking bread.

Phase three: development

Eventually steam pressure wins and the bean audibly pops — first crack — the doorbell announcing the final phase. Everything from first crack until we drop the batch is development time, when roasty flavors form and acidity softens. Development time as a percentage of the total roast is the development time ratio (DTR) — one of the numbers we log on every single batch.

The house move

Our signature is simple to describe and fussy to execute: we stretch the Maillard phase — giving those sweetness-building reactions extra minutes to work — and keep development short, usually under a 20% DTR. Long middle, quick finish. The result is the thread running through almost everything we roast: rounder, sweeter cups that keep their origin character instead of trading it for generic “roast” flavor. It's how a bright, young-tree coffee like our Primer Paso gets described around the shop as “grapefruit with sugar on it” — the grapefruit came from Colombia; the sugar came from the Maillard phase.

Curious how the roast connects to brewing? Start with extraction basics — the sugars we build here are the ones you're pulling out there.