First crack

Definition

First crack is the popcorn-like sound when cells rupture and steam leaves the bean. Many roast profiles start “development” at the onset of first crack. Hitting it too hot or too fast bakes the roast; dragging it too long flattens acidity. Second crack is a later, oilier stage. Listen, log bean temperature, and do not treat a phone recording as a lab sensor.

Calculators that use this

• Coffee roasting

  Roast Development Time Ratio Calculator

  Compute development minutes and DTR percent from time to first crack and total roast time. A clock ratio, not a colour meter.

• Coffee roasting

  Roasting Rate of Rise Calculator

  Compute rate of rise between two bean temperatures over a time interval. RoR is the slope, not a flavour name.