turning green coffee beans into delightful cups of coffee

Which is better: roasting at 420 degrees for two minutes, or 440 degrees for 1 1/2 minutes. Which is best? Which provides most heat to the coffee beans?

I DUNNO! But maybe it helps our understanding of the process if we think about "heat units", which would be temperature multiplied by time.

And it would also help if we could picture it. The labeling system on this website creates a graphical display of time and temperature. Hopefully it helps us understand what's happening during the different phases of the coffee roasting process.

"Heat units" are shown for each phase, and also the total "heat units" for the entire roast process.

The best way to understand this is to print a sample label.