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Between The Cracks
Ringo
Top  #26 Print Post
Posted on 02/02/2012 3:47 PM
On my home built drum roaster 1st crack can be tricky. I need a boost of heat right before 1st crack to make sure it happens. After 1 st crack starts rolling I really drop the heat input to control rise in Bean Temp. The reaction is almost self sustaining for 40 seconds or so as the beans make heat. As I see the rate of rise on the bean temp slowing I have to come back on some heat to keep the beans moving. Its a tough little balancing act sometimes and can keep you on your toes. After 1st crack I watch Environmental Temps, they drop for the first 40 second but bean temp keeps going up as bean temp ROR starts slowing I come back on the heat till the environmental temp start a slow rise, bean temp always follows. It great when it works but if you come into 1st crack with too many or too few BTUs in the drum its hard to catch up. I would love to run a commercial drum for the day to see how they run.
All you need in life is ignorance and confidence, and then success is sure. Mark Twain
 
jedovaty
Top  #27 Print Post
Posted on 02/02/2012 5:06 PM

Quote

freshbeans wrote:
...I can't speak to drum-roasting..but on my machine, RoR will begin to flatten out at 1C . At that point, I continue dropping velocity and fuel to maintain my desired inlet temp.... while not allowing beans to fly all over the place.
Would RoR start climbing again all by itself? I don't know for sure anymore, due to my adjustments.
However I do recall the 'stall' you are referring to . I always assumed it was from evaporational cooling (moisture leaving the beans), and yes, RoR would pick up again after this 'stall'
Have you encountered this 'stall' yourself? -Scott



Scott, was directed to my question? If so, I didn't have a specific type of roaster in mind, just based on what I've read people ramp up heat during first crack then right at the end dial down, and it seems to correlate with the beans. I was asking the question because my roaster seems to be acting a little different, as the ROR on mine slows down once I'm into FC, not before.

Yes, I get the "stall" on my kkto, much less so now that I've made a few changes. Based on what I've read by farmroast/Ed, you can fine-tune the "evaporational cooling" --> faster agitation should, in theory, help get through the decreasing ROR.
 
JETROASTER
Top  #28 Print Post
Posted on 02/03/2012 8:51 AM

Quote

jedovaty wrote:

Quote

freshbeans wrote:

However I do recall the 'stall' you are referring to . I always assumed it was from evaporational cooling (moisture leaving the beans), and yes, RoR would pick up again after this 'stall'
Have you encountered this 'stall' yourself? -Scott



Scott, was directed to my question?>>>> ROR on mine slows down once I'm into FC, not before.



Yes Sir....directed to you. I'm still not sure how much of the stall is attributed to the bean mass loosening up... or moisture leaving the beans. This is why I'm curious about your experience.
As it happens during 1C, it makes it more of a mystery...at least to me.

I run with the assumption that 1C is a point at which expanding moisture is quickly leaving the bean...which could slow RoR.

It's also a point where the bean mass seriously loosens up....perhaps slowing RoR.


Is it one...or the other...or both...or something else??? -Scott
 
jedovaty
Top  #29 Print Post
Posted on 02/03/2012 11:45 AM
Scott, I wish I knew the answer for you, but I have no idea. Based on my observations and experiences (despite being a total newbie to both roasting and drinking coffee), all I can say is that my roaster needs heat to make it through 1C/FC, which I think is what others experience, but mine was a bit to the extreme.

It's very plausible the evaporation causes the the slowing ROR, think sweating and exercise. Expansion probably slows it down, too, but allows the stall to complete more quickly by making greater surface area.. ? *shrug*
 
John Despres
Top  #30 Print Post
Posted on 09/15/2012 4:08 PM

Quote

mk1 wrote:

Wow, thanks for the Ruling the Roast Link John. That has answered many questions and is quite a jumping off point for me... into the deep end of the roasting pool. I have a lot to try, and now with a much better idea of what to look for.

Mark


Unfortunately, that link is now dead... Sigh. At least I have them all in print in Roast Magazine.

John
Respect the bean.
John Despres
Fresh Roast 8, Gene Cafe, JYTT 1k, Quest M3, Mazzer Mini, Technivorm, various size presses and many more brewers.
 
Web
JETROASTER
Top  #31 Print Post
Posted on 10/31/2012 8:15 AM
I was just looking at Allens post on a quick finish drum profile.

http://forum.home...ad_id=2985
It is likely too bright for espresso....but why?
I usually stretch between 1C and 2nd for an espresso...it tastes better.

Is the stretch beneficial because I'm waiting for something to develop, or am I cooking away something I don't want?
-Scott
 
erik82
Top  #32 Print Post
Posted on 10/31/2012 8:47 AM
Hi john,

Got a question here. You quoted that you aim for 4 minutes from the end of 1C to EOR for development of the flavours. From what I've read on HB (Ken Fox especially writes a lot about this) and the articles from Boot, they state that it should be 4 minutes from the beginning of 1C to EOR.

What are your thoughts about this? I've got about 120 batches now on my Gene and really love it but always aim for 4 minutes between beginning of 1C and EOR.
Olympia Cremina 2013, HG one 83mm #0083, Gene Cafe.
Also Zassenhaus grinder, Chemex, Abid Clever Dripper, Kalita Wave, Aeropress, Hario Buono, Bodum Cafetiere and Bialetti Mokapot
 
John Despres
Top  #33 Print Post
Posted on 10/31/2012 1:03 PM

Quote

erik82 wrote:

Hi john,

Got a question here. You quoted that you aim for 4 minutes from the end of 1C to EOR for development of the flavours. From what I've read on HB (Ken Fox especially writes a lot about this) and the articles from Boot, they state that it should be 4 minutes from the beginning of 1C to EOR.

What are your thoughts about this? I've got about 120 batches now on my Gene and really love it but always aim for 4 minutes between beginning of 1C and EOR.


Well, that's embarrassing. I misspoke and I've corrected the error. Thank you for the head's up!

Mea Culpa
Mea Culpa
Mea Culpa

John
Respect the bean.
John Despres
Fresh Roast 8, Gene Cafe, JYTT 1k, Quest M3, Mazzer Mini, Technivorm, various size presses and many more brewers.
 
Web
erik82
Top  #34 Print Post
Posted on 11/01/2012 6:03 AM
You're welcome. Did you gave up on drying or do you still think it is of any use for the whole chemistry of roasting?
Olympia Cremina 2013, HG one 83mm #0083, Gene Cafe.
Also Zassenhaus grinder, Chemex, Abid Clever Dripper, Kalita Wave, Aeropress, Hario Buono, Bodum Cafetiere and Bialetti Mokapot
 
cody
Top  #35 Print Post
Posted on 01/02/2014 5:00 PM

Quote

John Despres wrote:

Quote

mk1 wrote:

Wow, thanks for the Ruling the Roast Link John. That has answered many questions and is quite a jumping off point for me... into the deep end of the roasting pool. I have a lot to try, and now with a much better idea of what to look for.

Mark


Unfortunately, that link is now dead... Sigh. At least I have them all in print in Roast Magazine.

John


To anyone reading through this thread, the fantastic Willem Boot article being discussed is actually still available here, in pdf form:

http://bootcoffee..._Mar04.pdf
 
Cheekius Geekus
Top  #36 Print Post
Posted on 08/03/2016 4:17 PM
All of the Willem Boot articles referred to on the first page of this thread are still available at the Wayback Machine: https://web.archi...icles.html

I'd recommend right-clicking and Save File As... to save yourself local copies of the PDFs and Word documents.
 
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