Roasting · 5 min read

First Crack – How Roasting Works

Roasting turns hard, grassy-smelling green beans into fragrant coffee. The most important moment has a sound: the «first crack».

Roasting over time

DRYINGgreen → yellow

BROWNINGMaillard, aromas

FIRST CRACKdrinkable from here

From green to brown

Green beans hold a lot of water. In the drum or hot-air roaster they first dry out, turn yellowish and then begin to brown. In this phase the Maillard reaction creates hundreds of aroma compounds – the same reaction as in baking bread.

First and second crack

At around 196 °C the beans audibly pop open: the first crack. From here the coffee is basically drinkable – light roasts are stopped shortly after. Roast on and the quieter second crack follows; now oils emerge, and the coffee turns dark and roasty.

The art of the curve

Roasting is a craft: how fast the temperature rises and when you stop decides acidity, sweetness and bitterness. Good roasters find the right «curve» for each bean – and taste the result afterwards in cupping.

In short: While roasting, the beans dry and brown until they burst open at first crack – from there coffee is drinkable. When you stop determines the roast level.

Taste it

Where roasting happens in-house

Nº 01Die Quartier-RöstereiIn-house roastery Nº 08Die KaffeewerkstattFilter of the week Nº 20Der GeheimtippSaturday filter