coffee.sucks / THE LAB

Turn the dials.
Read the roast.

Six starting points. Endless decisions. Shape a roast, play with heat and airflow, and discover how the next move changes the curve.

FREE MEMBERSHIP · INVITATION ONLY

Your next roast starts with a seat.

Record your burner and air decisions, adjust the three phases, save private profiles and explore the advanced studies inside coffee.sucks. Each member has just two invitations.

I have an invitation ↗Join the waitlist

No invitation yet? John releases a limited number of waiting-list seats each month, in signup order.

FROM THE NOTEBOOK

Curve studies.

Explore saved time and temperature samples with calculated RoR and labelled roast phases.

FROM CURVE TO CUP INTERACTIVE NOTES

A balanced progression

Follow an illustrative roast from charge through turning point, colour change, first crack and drop. Temperatures are example probe readings, not targets.

ROAST TIME00:00 / 10:00
BEAN TEMPERATURE205.0 °C
ROR · SMOOTHED— °C/min
Ready to explore

RoR uses the trailing 15 seconds; shown after charge recovery. Select a curve dot to read its note.

BEAN TEMPERATURE · °CROR · °C/MIN
A balanced progression: bean temperature and smoothed rate of rise over roast timeAn illustrative roasting profile lasting 10:00. Bean temperature uses the left axis in degrees Celsius. Mint RoR uses its own adaptive right axis in degrees Celsius per minute and a trailing 15-second average, hidden until 15 seconds after the turning point. Press play for a compressed educational playback, or use the time slider and stage buttons to explore the observations.
ROAST TIME · MIN:SEC
Bean temperature · left axisSmoothed RoR · right axisEducational playback · time compressed
Drying
50.0%05:00
Maillard
30.0%03:00
Development
20.0%02:00

Share of total roast time, from marked events.

Drag to explore the roast
10:00 roast · approximately 24s playback at 1×
AT THIS STAGE00:00

Charge

Coffee enters the roaster. The probe reading falls as the beans absorb heat.

JUMP TO AN OBSERVATION

COLOUR IS ANOTHER CLUE

Recommended bean colour

Agtron Gourmet · whole bean

55–65
20 · darker100 · lighter

An editorial starting target, not a measured result. The simulator does not calculate Agtron from temperature. Confirm colour on your actual coffee and cup it.

How to compare colour

Higher numbers are lighter. Keep the instrument, scale, sample preparation, temperature and time after roasting consistent. Whole-bean and ground readings describe different samples; do not substitute one for the other.

The SCA cupping roast target of 63 on the Gourmet scale is for ground coffee. These whole-bean ranges are learning suggestions, not SCA roast classifications or origin-specific standards.

Illustrative sample · not a roast recipe

These are educational simulations and curve studies. Probe readings, airflow response and first crack vary with the coffee, machine and measurement setup. Taste and physical observations are needed to assess a roast.

Explore the upcoming roasting class ↗