Roasting it: three landmarks that jump all at once
A decaf in the drum: color, probe and crack all go off
Three landmarks go off together: the color of the bean, the needle of the probe and the sound of the first crack. Follow the needle. Start the scene or choose a step.
Swelling and drying have caramelized some of the surface sugars: color, the roaster's main landmark, is no longer of use. Rely on time, the probe and smell.
Read the stages without animation
- It starts out already brownSwelling and drying have caramelized some of the surface sugars: color, the roaster's main landmark, is no longer of use. Rely on time, the probe and smell.
- It heats fasterLess residual moisture, so less water to evaporate, so less thermal brake. Charge cooler, rise slowly and watch the rate of rise.
- The first crack is timidThe weakened cell releases its steam gradually instead of bursting all at once. It is smelled rather than heard: the smell changes before the noise arrives.
- After the crack, everything speeds upDegraded structure and lighter bean: development flies by in a few seconds. Lower the gas steadily during development rather than all at once.
- It goes rancid fasterThe oils migrate earlier to a more porous surface and oxidize there: smaller lots, faster turnover, a valve bag.
To remember: On a decaf, what you see, what you hear and what the probe says all go off at the same time.
In history: A separate profile calls for a separate lot: many craft roasters instead push decaf darker.
Read the full article and its sources ↓A roaster works with three instruments: what is seen, what is heard, what the probe says. On a decaf, all three go off at the same time. That is why a coffee that promises to be hard to roast is almost never an exotic bean, but an ordinary decaf.
| What changes | Why | What is done |
|---|---|---|
| The bean starts out already brown | Swelling and drying have caramelized some of the surface sugars | Give up color as a landmark and rely on time, the probe and smell |
| It heats faster | Less residual moisture, so less water to evaporate, so less thermal brake | Charge cooler, rise slowly, and watch the rate of rise |
| The first crack is timid | The weakened cell releases its steam gradually instead of bursting all at once | Smell it rather than hear it: the smell changes before the noise arrives |
| After the crack, everything speeds up | Degraded structure and lighter bean: development flies by in a few seconds | Lower the gas steadily during development rather than all at once |
| It goes rancid faster | The oils migrate earlier to a more porous surface and oxidize there | Smaller lots, faster turnover, valve bag |
There is an economic consequence to this list, and it explains a good part of what is found on the shelf. A decaf needs a separate profile, so a separate heating, so a separate lot. For a craft roaster who sells ten bags of decaf a year against a thousand of regular coffee, that means devoting machine time and test material to a marginal line.
Many do not do it and simply push the decaf darker, which hides the defects under the roast. Hence the ash taste that so many people associate with the word. The process has nothing to do with it, the commercial trade-off does. See roasting.
In this plateThe 14 sections
- 01The problem comes down to one sentence of chemistry
- 02Decaf: from Bremen to Sanka
- 03What caffeine-free coffee built in Bremen
- 04Why decaf coffeepots are orange
- 05The processes, one by one
- 06The processes specialty coffee is inventing
- 07The methylene chloride quarrel
- 08What the bean really loses, and what is attributed to it
- 09Roasting it: three landmarks that jump all at once
- 10Who decaffeinates, and where: a handful of plants worldwide
- 11What it costs, and why decaf is more expensive
- 12The extracted caffeine: which of the two is the by-product?
- 13The other route: coffee plants that make none
- 14The questions people ask most often
The table of contents, with the first sentence of each section