I want to thank Logan Collinge of Mojo The Beanery for spending several weekends roasting to order for me, and being such a mine of information.
The first experiment was to take one single origin green bean, and have Logan roast it to common roast levels across the roast spectrum.
The selected Green Bean was a Guatemalan – El Coygoyal, with the following roast levels:
Light City
Half City
Cinnamon
Medium
City
American
Breakfast
Dark
Full City
Vienna
Darker than dark
This enabled me to test, extend and refine the computer model.
Testing was making two cups of coffee at a time, A/B. One using the predicted model settings, the other cup shifted up or down the SSDI scale, or varying one parameter e.g ratio. Taste testing used my partner, and various long suffering work colleges, to gain opinions other than my own. Both espresso and filter methods were tested. Testing also was done over the period of a couple of months, to determine the optimum age after roasting for each roast point.
The experiment had to be repeated a second time. This time using specific drop points to fill in some data gaps. A different Single Origin Coffee, a Brazillian – Sito Pedra Menina was used.
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205
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The results formed the Rules of Thumb, which is the 150 data point scaffold of the full 5000 data point SSDI.