Diedrich IR-5 Analysis by Chris Kornman
After a few recent excursions with Geshas from Guatemala and Panama, I brought a similar approach to this macerated honey coffee from Colombia. The basic recipe is this: a moderate charge temperature with a reasonably long low-burner soak, followed by a big increase in heat to power through into the color change. The idea is to get about a 50-35-15% ratio, slowing the pace mid-Maillard to coast gently through crack at a low rate of rise and end with a light color but decent amount of development time.
In this case, I ramped up my burners all the way to 100% by minute 2, giving me enough momentum to start dropping the burners by 5 minutes, when color change was observed. I also followed an early-standard airflow profile: closed at the charge, halfway at the turning point, and open by color change. The roast proceeded easily according to plan the coffee seemed happy to absorb heat when it was given, but not overly prone to crashing when gas decreased and airflow increased.
First crack rolled in slowly, which I should’ve taken as an indication that a little push might’ve been needed at this point. Post crack development here lasted a little longer than 90 seconds; I kept holding on for just a little more color development. This might be the one area to really pay attention to your rate of rise. I usually like to let these types of roasts, for these types of beans, drop to nearly zero right as I open the drum door. In this case, the roast plan was followed but the coffee seems to need just a little more heat towards the end of the roast, so use caution when dropping those burners as you approach first crack.
Colortrack indicated that the roast came out in spec on the light side (I prefer to try and preserve those floral notes in Geshas with light color readings). Taking the coffee to the cupping table, Sandra and Doris joined me to evaluate – I always appreciate additional perspective tasting my own roasts, it’s just terribly hard to be objective. In this case, I brought a little concern about underdevelopment to the table and felt the coffee tasted a hint grassy at first.
Sandra noted a strong rose-like and carnation fragrance with a lot of sweetness as the coffee cooled, and Doris found complex, sweet citrus notes in the cup like mandarin orange and Meyer lemon. Softer fruit notes were present as the cups extracted: some hints of apricot and cantaloupe, and a distinct vanilla-like creaminess.
Looking back, this was a really solid first attempt at roasting the coffee. Given a second chance, I’d probably look to enter first crack with a little additional momentum and a slightly higher drop temperature, perhaps in exchange for a slightly shorter development time to see if a bit of extra caramelization would benefit the intensity of the brew.
