Roasting coffee with "evenness" as the goal - Page 4
- Almico (original poster)
- Posts: 3612
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Tell that to my feet and back!jammin wrote:Almico, that's awesome! You're live'n the dream:)
Do you have a write up anywhere on your story or a blog?
Practically every step of the journey is spread throughout H-B.
- drgary
- Team HB
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Christopher,archipelago wrote:Another thing I see mentioned here is about how "high airflow strips moisture". <snip> I reckon that the issue with too high airflow has less to do with wicking of surface moisture (there isn't much) and more to do with the amount of BTUs you have to shovel into a roasting environment to compensate for the lack of radiant heat. You'll have a lower ET in a high airflow situation, with higher BTU at the burners (and thus likely a hotter drum) than if you have a lower or more balanced airflow settting (requiring lower flame while maintaining higher ET)
I've worked with higher airflow and lower temperature on my perforated drum roaster and wound up with undrinkably tasteless, papery coffee. I don't think my drum was hotter. I had cranked up the airflow to maximize heat exchange from the burners, so more BTU's must have been transferred to the coffee. If the effect is not the wicking of moisture on the surface, what changes in the bean typify the roast defect?
Gary
LMWDP#308
What I WOULD do for a good cup of coffee!
LMWDP#308
What I WOULD do for a good cup of coffee!
- aecletec
- Posts: 1997
- Joined: 13 years ago
Roasting on a FZ-94 I use much higher airflow than the lighter test, but it's electric so must have lower BTU than DrGary's perforated gas roaster... no trouble with papery tasteless coffee.
I think it's important to stay away from assuming that surface moisture wicking is the default position, given it's a guess - unless someone has direct evidence for it?
I think it's important to stay away from assuming that surface moisture wicking is the default position, given it's a guess - unless someone has direct evidence for it?
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- Posts: 138
- Joined: 8 years ago
Definitely a worthy inquiry, I absolutely believe you - my guess is that it's actually baked... that the bean pile experiences a drop in temperature due to the airflow, rather than allowing a pillow of radiant heat in a lower airflow environment to continue the cooking at the endothermic flash eventdrgary wrote:Christopher,
I've worked with higher airflow and lower temperature on my perforated drum roaster and wound up with undrinkably tasteless, papery coffee. I don't think my drum was hotter. I had cranked up the airflow to maximize heat exchange from the burners, so more BTU's must have been transferred to the coffee. If the effect is not the wicking of moisture on the surface, what changes in the bean typify the roast defect?
- drgary
- Team HB
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- Joined: 14 years ago
Thank you. I doubted at first that there is less heat to the beans. Even though airflow was set to reach 1C fastest with a burner on high, setting that airflow constant with a lower burner would bring more air to the beans to get the heat to the surface, which might heat the surface but not penetrate. To not hijack this thread I've started another to explore this question.
How does high airflow strip flavor from the bean?
How does high airflow strip flavor from the bean?
Gary
LMWDP#308
What I WOULD do for a good cup of coffee!
LMWDP#308
What I WOULD do for a good cup of coffee!
- jammin
- Posts: 753
- Joined: 14 years ago
TL;DRAlmico wrote: Practically every step of the journey is spread throughout H-B.
- farmroast
- Posts: 1623
- Joined: 17 years ago
Just saw this thread.
Evenness of roast I think is a huge problem with drum roasters. Poor agitation and a mix of uneven heat transfer, Especially with a really clean single variety, screened lot. Fluid beds have evenness issues too, along with the high volume of oxygen washing. That was why I designed my homebuilt hybrid in '06 with the high speed mechanical agitation, thin ss pot. Still roasting on it, have no interest in roasting on anything else
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Evenness of roast I think is a huge problem with drum roasters. Poor agitation and a mix of uneven heat transfer, Especially with a really clean single variety, screened lot. Fluid beds have evenness issues too, along with the high volume of oxygen washing. That was why I designed my homebuilt hybrid in '06 with the high speed mechanical agitation, thin ss pot. Still roasting on it, have no interest in roasting on anything else
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LMWDP #167 "with coffee we create with wine we celebrate"
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Same conclusions here after explored all available roasters build.
Mechanical agitation, average airflow, and all three heating methods combined, not equally balanced, the most IR, then convection, and the least conduction. Somewhat resembling a Stronghold S7, with other airflow path.
Mechanical agitation, average airflow, and all three heating methods combined, not equally balanced, the most IR, then convection, and the least conduction. Somewhat resembling a Stronghold S7, with other airflow path.
- Almico (original poster)
- Posts: 3612
- Joined: 10 years ago
The Stronghold S9 is something to behold...
Any pricing out on this puppy?
Any pricing out on this puppy?
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- Posts: 15
- Joined: 9 years ago
Pursuing eveness in coffee is a hard goal to follow. Unless you have new high tech system such as loring it will be hard to attain it in classic drum system as there's still some conduction heat transfer. Attaining eveness is easier in convection type of heat method.