I was so excited to get a roast of the Ethiopia Deri Kochoha from Mark Michaelson of Onyx Coffee Labs in Fayetteville, Arkansas. It was a lovely roast of the coffee with so much of the honey sweetness paired with ginger and citrus that popped out in the brew. Mark reached out to me to ask how the coffee was, and so I turned it around on him and barraged him with questions about his approach to roasting.
Mark M: what did you think of it?
Chris S: Yeah man! It's great. Real sweet and brews nice. The brightness is nicely balanced. Get a lot of that honey ginger in the cup. What was your approach to roasting it?
MM: thanks a lot. I'm stoked that you liked it. I approached the coffee with a traditional Diedrich method; air at 50% at around 265-70 and air at 100% at around 365-370. I stretched out the carmalization stage to highlight the sweetness. development is between 1:45-2:00mins after 1st crack. stopping the roast at 405 degress
CS: Nice. How does this differ from how you approach other coffees, or does it?
MM: I have found that most Ethiopians roast well within that range, at least on our IR12. It took me a while to figure a Diedrich machine does not roast within the timeframe that a Probat does.
Though, with all African coffees presenting different challenges, the end result differs greatly, as you are well aware
CS: Did you learn on a Probat?
MM: No I did not learn on a Probat, but all the blogs I read, people I talked to, and instructors Iearned from all taught with a Probat style roaster in mind. As you know, one cannot roast on a Diedrich the same. I constantly thought I was failing as a roaster because I could not roast within the timeframe of a Probat type roaster. It wasn't until Charles Babinski used our coffee for both of his runs last year, when he won his division and placed second in the country, that I realized I was doing something right. He and his team thought our Gesha was the best they had tasted all year
CS: Rad! That's such a great answer too, and you're right. Don't get me wrong I love a Probat, but I do totally get your point. Did you home roast?
MM: No I actually started on the IR12. I then started roasting on a Quest. Now I also roast on a old school IR40
CS: Oh wow! Not a lot of those around. They don't build IR's past the 24 anymore. How does the 40 differ from the 12?
MM: I found that the 12 is more powerful. I can safely roast a dark roast at 23lbs and still be fully in control. The 40 cannot do that. I thought the 40 would be a lot more powerful. But the max btu is only 180,000. So the biggest batch size I can roast on it, with full control is around 55lbs. I guess that is understandable though, given that 55lbs is around 70% capacity. Also, the 40 has a separate blower for just cooling the beans, which is awesome. And we modified the 40 to use the new school cooling tray arms that are on the 12. I really hated the wire brushes it had on it previously
CS: Oh man, wire brushes are the worst! So many finger pokes. Yeah, I believe that's why they stopped going that big with the IR technology, just couldn't get enough umph at that size. How about working with the Quest? Do you feel it allows you to play with profiles before trying to execute on the production roaster? Do you still have both prod roasters?
Face the 40
MM: Yeah i use the 40 for our house, all our espressos, our euro shade and decaf. The 12 is used for all our single origins. The Quest allows us to decide on whether to purchase the coffee or not. I have not been able to translate what I do on the quest to the 12 or 40. Do you have any suggestions?
CS: Well, it's definitely a scale issue, but I would also add that the elements on the quest are actually much more responsive then a traditional electric or IR burner.
I would say that the "moves" might not be the same, but as far as looking at a coffee and shortening or stretching different parts of the roast it can give you a pretty clear picture, and also I feel like with the controllability in general and the dynamic with the air flow that the cup itself can taste pretty close to the IR.
Brothers in the jungle, cousins on a Quest