Roasting Costa Rica

Roasting Costa Rica

Brothers; Mauricio, Marvin, and Greving Corella, have been growing coffee their entire lives. They own a total of 50 hectares dedicated to producing varietals of Caturra and Catuai. Since 1989 it has been illegal to grow any other type of coffee than Arabica, Prohibiting the growing of lower-grade coffee and encouraging farmers to strive for excellence. Through the months of December till April, the population in the area triples with people returning to work on the farms for the harvest. For this lot all of the coffee is hand-harvested, meticulously picking only ripe cherries. They are delivered on the same day to the Palmichal Mill, to be processed. This lot is fully washed and dried mechanically at temperatures not exceeding 37.5ºC. The cup is well-balanced, with bright stone fruit acidity. Flavour notes of peach, honey and black. Perfect for filter or espresso.

Costa Rica’s many microclimates and varying soil types result in striking differences from region to region. This lot, grown in the subregion of Naranjo de Dota in Tarrazu, which is renowned for its acidity and heavy aroma can attribute a lot of its defining characteristics to the High altitude which allows for a slow cherry development, This slower development mixed with the culture of hand picking and striving for quality is one of the reasons Costa Rican coffee is highly regarded.

Anita's Costa Rica Aillio Bullet Roast

Costa Rica Naranjo de Dota, Tarrazu – Medium Omniroast
Duration: 9:41min
Charge Temp: 160
Colour Change: 4:21 min, 140
First Crack: 7:43, 180
Weight Loss: 14.5%
Flavour Notes: Peach, mandarin, black tea, honey.

Moisture Content: 10.7%
Water Activity Reading: 0.59aw
Density: 645g/l

Heading into this roast I really wanted to preserve light floral notes, so I opted for a smaller batch size of 400g.  At this size I find we get a good amount of control and can keep the roast momentum rather fluid.  The Costa Rica lot is super versatile, so I went for an Omni roast, which is somewhere in between a filter and an espresso roast. The main obstacle I find when trying to get a versatile roast is preserving enough of the acidity while creating something that is still easily drinkable as an espresso. Balance is hard and can take a bit of practice, we found that the acidity held up relatively well when brewed through a drip filter. The stone fruit acidity was gentler and more balanced, not as nippy, and bright as a cupping roast.  The sweetness was more highlighted, as was the body in the cup from the extra time spent developing the roast. The screen sizes were relatively large, with a 74% majority sitting above Sc17 and about 22% on Sc15/16.  This makes it easier for the coffee to take on the heat, creating a more even colour distribution once roasted because they crack at the same time.

The Aillio bullet is quite responsive and as the drum isn’t a big heavy piece of iron I have had good results with lower charge temperatures. For this batch I charged 400g at 160°C, allowing for a 1 min soak on P1.  It was increased to P9 after a minute this achieved a good ramp up, reaching a high of 17.3 Rate of rise (ROR)/Min.  for a Costa Rican, this coffee is not super dense, however, this density tells me to take an easier approach heading into the first crack.  We didn’t want the roast to take off, so I applied plenty of heat at the start, but once there was a good momentum through the coffee I eased back relatively quickly as we go into the first colour change.

I started with lower airflow with settings at F2 but moved the fan to F3 hoping to increase the ROR through the drying phase. The Costa Rica had other plans, with the colour change holding out until 4:20min mark. For this coffee I found, it is best to let the coffee roast itself. This approach lets the coffee roast organically, and sometimes it will end up a more balanced roast. You can’t always bend it to your will.

I spent 33%, 3:22min of the duration in Maillard phase, to help create those sweet honey notes and drive it gently into first crack, still maintaining a 10°C ROR before crack. Note the fan increases slightly, as the power decreases towards crack.  This helps create a steady ascent in slope on the ROR.

Power was on P4, fan on F5 before crack. The crack was popping and consistent at a ROR of 9.7-10 degrees. It decreased steadily, without any changes to power or fan, though the fan was increased to F6 to remove the smoke from the chamber towards the end of the roast. The coffee spent about 2min, 20% in development. It increased in development by 11°C, cracking at 180°C and ending on 191-192°C.