Justin Carabello from Carabello Coffee in the Cincinnati area answered the call to talk about roasting, sending me a number of different shrub coffees roasted on his Primo 5K, including the Corazon Del Robot blend and a blend of his own using some shrub coffees which I was stoked to see. I love single origin coffees, but as you may have read in my Make Friends with Blends post - http://coffeeshrub.com/shrub/blog/make-friends-blends - I feel like the art of blending is something that has really been overlooked lately.
Justin was also kind enough to share his full profiles for his coffees. One thing we talked about in relation to his profiles was trying to trim just a bit of the total roast time down in order to get some of the characteristics of the coffees to pop out more particularly in the dry processed Ethiopia Kochere, without estranging his clientele in the area with going too light on the roasts. I was really into his roast of the Sumatra Toba Batak PB, with the longer roast time taking some of the edge off of the more herbaceous aspects of the cup and really pushing the green grape tartaric character in this coffee in a really nice way.
The Roaster Walk, in Justin's words:
I am roasting on a Primo 5 kilo. At present, I have no way to adjust airflow, so it is always the same. I have two burners, one high (HB) and one low (LB). The lower burner is the larger of the two. When I roast I am able to control when these burners go on or off, but when they are on they are on at 100% their BTU output. You probably already know all this, but I am telling you just in case you don't. You will also noticed that I list a coast time. This is how long I wait from the time when the coffee is dropped into the drum before I turn on the burners. The temperatures I list for the burners are the temperatures that my bean probe reads when they are set to turn off.
All that said, the man who trained me on this roaster had a roasting business and used it for 8 years. He had developed a 15 minutes roast profile that he modified from coffee to coffee. He trained me to aim to bring coffees to the point of first crack between 10:30 and 11:00 and to aim to finish the roast at 15:00. Since he roasted all of his coffees into (and many times beyond) second crack (Vienna and Roasted Coffee Pictorial Guide. ">Light French), his profile did a good job of getting some nice post first crack development before gradually entering into second crack.
I have been using this machine now for nearly two years and have gradually lightened up all of our coffees. Presently I am roasting most of our coffees in what I perceive to be the CIty+ to Full City range with the exception of one dark roasted coffee we offer (the SM French Roast). I really like the flavor profiles of most of what I get in this range, and I am getting really good feedback from our growing customer base as well.
That said, our customer base is mostly what I would call Midwest people who want to enjoy a really good cup of coffee, but they are not yet ready to weigh out their beans on a scale before grinding them - albeit I do have some of those. For many, the fact that we offer them fresh roasted coffee and that we are local and also a philanthropic roaster that is taking our profits and putting them ito some projects in Nicaragua and Kenya, makes us a good choice since we give them some really nice coffee as well as an opportunity for them to shop their conscience and be a part of a bigger story.
So... with these coffees, I think that I am still not getting the most I can get out of them as far as flavors I can. I am going to guess that, once you taste them, you may tell me that I am overdeveloping them. My goal is to get them to a point where they have the best balance of sweetness and body. I don't mind a little roast influence, and I guess I may be a little scared of going too light and having people find the coffee tart or too bright for their palettes.
I am largely self taught, so, I am very open to any and all criticisms and suggestions. I am looking for the best way to grow in my understanding so that I can improve what I am doing. Our business is growing at a very solid pace and we are beginning to take on some nice wholesale clients in the Cincinnati area. we have a fiercy loyal and growing customer base. I believe we are in a great position, and that anything I can do to help improve my roasting and ability to connect people more meaningfully to the coffee will be well worth my time and energy.
Here we go on the coffees:
1. La Corazon del Robot Espresso
Weight - 10.5lbs
Drum Temp at Charge - 360
Coast Time - 1.5 minutes
HB Temp - 320
LB Temp - 370
First Crack occured at 368 degrees at 10:30 into roast and lasted until 13:00
At 12:30 I turned the LB back on for 10 seconds (398 Degrees), and again for 10 more seconds at 13:00 (400 degrees)
Dropped roast at 410 degrees at 15:00
2. Sumatra Toba Batak Peaberry
Weight - 5.0lbs
Drum Temp at Charge - 330
Coast Time - 3.25 minutes
HB Temp - 160
LB Temp - 363
First Crack occured at 370 degrees at 10:25 into roast and lasted until 12:00
Dropped roast at 417 degrees at 15:00
3. Ethiopia Grade One Kochere Dry Process
Weight - 7.0lbs
Drum Temp at Charge - 350
Coast Time - 3.5 minutes
HB Temp - 190
LB Temp - 363
First Crack occured at 375 degrees at 11:00 into roast and there was still a few cracks when the roast was dropped.
At 13:30 I turned the LB back on for 15 seconds (405 Degrees).
Dropped roast at 412 degrees at 14:45
4. Winter Blend
This is a post roast 50-50 blend of the Sumatra and the Ethiopia.
5. Colombia Pedregal Lot 172
As I do not have a sample roaster, this was the second of two one pound roasts that I did of this new coffee. During the first I was really surprised at how FC seemed to stall nearly right away. So, you will notice that I added some heat at FC on this roast to help guard against that.
Weight - 1.0lbs
Drum Temp at Charge - 307
Coast Time - 5.5 minutes
HB Temp - 160
LB Temp - 352
First Crack occured at 385 degrees at 11:00 into roast. I did not note when it stopped.
At 11:00 I turned the LB back on for 10 seconds (385 Degrees), and then again for 5 seconds at 12:00 (396 Degrees) and for 10 seconds at 12:30 (399 Degrees).
Dropped roast at 413 degrees at 14:30
As you can see, when I am roasting I am trying to cut the LB off at a point that gets the coffee moving well into first crack, but also early enough in the roast so that the coffee does not rush through first crack. I am trying to get a good 2+ minute first crack time. This is really a challenge as it then also causes me to need to manually turn the burner back on to help keep the roast moving along at times.
- and here is Justin's follow up after he was able to reduce the roast times a little bit
Since your last feedback I have gone ahead with shortening my roast times to 14 minutes and have been very pleased. I am going to be sending you a sample of the change to the Ethiopia Kochere so that you can taste it. Generally speaking, it really has resulted in a cleaner, more complex experience on all of the coffees. And the Kochere was one of the coffees where those changes were most notable, not only to me but also to others.
It has been good to work through some of the nuts and bolts of how to arrive at the same finished degree of roast, but with starting at a slightly higher temperature and ending one minute earlier. I have been slowly training a young man to roast and this has been a really good experience for us to work through. Especially since many of our roasts vary in weight, which only adds to the fun!
Thanks again so much for sharing Justin, both your roasted coffees and your experiences with them. So excited to get get to share these experiences with others in hopes that it might help someone else get their heads around any problems they might be having.