Almico wrote:Not sure I agree completely. If it were possible to have 2 roasts with the same Agtron roast levels for whole/ground, same time to yellow, same time to 1C and same DTR, and yet one roast has a big crash and flick, the two roasts would certainly taste different even though the milestone requirements were met. The destinations are important, but the routes to the destinations are as well.
Although I can't prove
it, which the article admonishes, there is support for Alan's point in the details of the article. At one point Rob worked hard to "trick" the Diedrich roaster into creating a similar profile to the others without introducing roast defects. In my amateur experience I can introduce an awful and consistent air baked roast defect on my perforated drum TJ-067 with an airflow that's too high.
Back on topic, here's the quote that sums it up for me:
"... despite large differences in design, style, thermocouple measurement/placement, and heat transfer controls, people cannot easily discern a difference between the same coffee roasted on multiple, different roasting systems, provided the aforementioned methodology of profile matching is followed.
And even more significantly ... those who did pick the "off/different" cup in the triangulation could not specifically/clearly identify which roasting system the "off/different" cup was from."
And, the implications for a roaster operator:
"... the roast profile is the primary driver of coffee flavor. Matching duration and timing of key chemical reactions (modulation phases) as well as the extent of sugar browning, pyrolytic reactions and matching end color (WB/GR) are the key elements to matching a flavor profile .... as a roaster operator, you are ultimately in control of the flavor outcomes of the coffee you are roasting. With thorough knowledge of your machine and your green beans, as well as any potential agricultural variations that may influence flavor, you can adapt to match any style of roasting you would like, provided that you know where you want a key chemical reaction related to a specific flavor to occur."
Which mimics what has often been said here. If you're not getting the results you want, the problem is often on the barista side of the handle.