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Between The Cracks
JETROASTER
Top  #1 Print Post
Posted on 09/07/2010 2:12 PM
I think I have alot to learn about this topic. My roaster is probably too fast for it's own good.
Question 1; What's generally considered best practice? (time between cracks)
Question 2; If I move too quickly between cracks, what's the chemical result?
Links are helpful, personal experience is even better. I'll take either!
Thanks, Scott
 
John Despres
Top  #2 Print Post
Posted on 09/07/2010 5:20 PM
Personal experience:

Stretch between the beginning of first and the beginning of 2nd - I shoot for 4 minutes.

"from the first crack to the second crack, coffee beans develop their specific aromas and flavors, which, as coffee tasters know, can produce a very complex taste profile. At the end of the second phase, all free moisture has evaporated. The length of the second phase depends on the roasting degree, which can vary from region to region and from product to product."

Excerpted from Ruling The Roast I by Willem Boot http://www.bootco...icles.html The other 3 articles are also assigned reading.

Boot knows his stuff and is incredibly helpful. His articles are valuable no matter what stage roaster one may be from novice to experienced.

John

Edit: Used to say "Stretch between the end of first and the beginning of 2nd - I shoot for 4 minutes." That is wrong.
Edited by John Despres on 10/31/2012 1:01 PM
Respect the bean.
John Despres
Fresh Roast 8, Gene Cafe, JYTT 1k, Quest M3, Mazzer Mini, Technivorm, various size presses and many more brewers.
 
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JETROASTER
Top  #3 Print Post
Posted on 09/07/2010 8:14 PM
That's dead on! Thanks John. How about bean density?
Does a hard bean (typically)get the longer stretch?
-Scott
 
John Despres
Top  #4 Print Post
Posted on 09/07/2010 8:26 PM
More dense beans should get more heat at the onset, during the drying stage.

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.
 
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allenb
Top  #5 Print Post
Posted on 09/07/2010 8:39 PM

Quote

freshbeans wrote:
I think I have alot to learn about this topic. My roaster is probably too fast for it's own good.
Question 1; What's generally considered best practice? (time between cracks)
Question 2; If I move too quickly between cracks, what's the chemical result?
Links are helpful, personal experience is even better. I'll take either!
Thanks, Scott


This post is timely with the Harrar swap upcoming. I've heard many claim they get better, more defined notes when shrinking up the 1C to 2C with a Harrar (less than 3 m), more like 2 m.

Wondering if this has been experienced by anyone else and if it holds true, why?

Allen
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
John Despres
Top  #6 Print Post
Posted on 09/08/2010 7:30 AM

Quote

freshbeans wrote:
That's dead on! Thanks John. How about bean density?
Does a hard bean (typically)get the longer stretch?
-Scott


Stretch and taste, keep meticulous records of roast and brew. I'm coming on nearly 450 pounds in a half-pound roaster and I still tweak and stretch and play and then I drink the roast, either with great satisfaction or not so much...

A very loose guideline
More dense beans need more heat throughout the roast - Look at altitude, SHG, SHB.
Mid growns get moderate to high heat at the onset, but moderate through the rest.
Low growns, softer beans get lighter heat at the onset and throughout.

These notes are the starting point for each new bean I roast and I keep records and adjust for my taste buds, as they are the boss.

If your roaster is too fast, I think you should have the possibility to slow it down with various controls or actions. Shoot, a Fresh Roast 8 can roast batch in 4 minutes, but by simply throttling, I can make the roast last 12 minutes.

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.
 
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seedlings
Top  #7 Print Post
Posted on 09/08/2010 7:45 AM
The other very important sidenote to stretching between cracks is that the beans should NEVER drop in temperature. The chemical reactions are like softening glass, and a drop in temperature shocks the beans and stops the reactions.


*I read something to this extent somwhere (home-barista?. I may not have quoted it properly.
CHAD
Edited by seedlings on 09/08/2010 7:47 AM
Roaster: CoffeeAir II 2# DIY air roaster
Grinder: Vintage Grindmaster 500
Brewers: Vintage Cory DCU DCL, Aeropress, Press, Osaka Titanium pourover
 
JETROASTER
Top  #8 Print Post
Posted on 09/08/2010 4:06 PM
I'm beginning to discover 2 big problems.
I can barely hear the cracks (closed exhaust).
The gauges are suggestive at best.
I have some work to do. I've got a good idea about how far off the gauges are. I used that idea this morning and stretched things out a bit.
It was past crop Honduran. The results were noticable,even
without a rest. I expect this bean to be a bit flat, but to my surprise!! a respectable cup of coffee.

So... going to fast simply doesn't allow flavors to develop?
or does it present 'off' flavors?
-Scott
 
ginny
Top  #9 Print Post
Posted on 09/08/2010 5:22 PM
Well Scott:

Quote

So... going to fast simply doesn't allow flavors to develop?
or does it present 'off' flavors?


Both are true but yet again it is YOUR taste buds at work.
For me a too fast roast has garbage flavor; I can air roast in the Fresh Roast 8 and while I can drink it asap it is not really good but I want something NOW after I have forgotten to roast my own coffee. My garbage is better then the local yokel He Brew's that buys coffee 6 months old.

I think the resting time may be one of the biggest factors in how the flavors come through.

While I have tried to write down dates and times it seems to my palate that a darker roast will have a flavor burst after 5 days plus. The lighter roasts seem to develop within 3 to 4 days.

I drink every roast I roast as a cafe crema (an espresso if you will) or serve as a tumbler for others (read macchiato) and they love it especially ice!~

taste buds, taste buds and more taste buds.

I think this September roast comparison will be really interesting with CHADS last offering.

have a great evening,

ginnyShock
 
JETROASTER
Top  #10 Print Post
Posted on 09/10/2010 4:00 PM
I ran 2 batches of the Harrar. (Sivetz heat gun)
Batch 1; fast, right thru 1stC stopped at the first sign of second. Start to finish 5min
Batch 2; fast into 1stC, slowed things down until the first sign of second. Start to finish 8min.
...including 3.5 minutes after 1st.
Both batches look identical in whole bean.
As ground coffee, you can see the dif. Batch 2 has no light flecks.

On day one you could taste the dif. On day 2, even more pronounced.
Batch 1 had none of the apricot. Batch 2 was noticably more complex.

Both batches are likely still be too fast. We'll see what happens Monday.
Thanks all for the input. I better figure this out before I ship.
.....tough crowd. Thanks All -Scott
 
John Despres
Top  #11 Print Post
Posted on 09/10/2010 7:56 PM
Hey, Scott, how much time from beginning to the start of first. That part may be too fast yet. 3.5 minutes after first to second is quite respectable.
:Clap:

You're right, an 8 min roast is still pretty fast, but it sounds like you're beginning to dial in your roaster!

John
Edited by John Despres on 09/10/2010 7:57 PM
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  #12 Print Post
Posted on 09/11/2010 8:26 AM
Beginning to first was way fast. I didn't expect that from a little heat-gun. Monday I'll try again, toggling right from the start.
As far as dialing in my primary machine; I think I'm getting closer. Without the visual, or accurate gauges,
it still seems too much like alchemy.
I've been walking past my new hopper (incomplete)
for months. I think it will solve alot of these issues...someday.
-Scott
 
Indiana Randy
Top  #13 Print Post
Posted on 03/10/2011 5:04 PM

Quote

John Despres wrote:

Quote

freshbeans wrote:
That's dead on! Thanks John. How about bean density?
Does a hard bean (typically)get the longer stretch?
-Scott


If your roaster is too fast, I think you should have the possibility to slow it down with various controls or actions. Shoot, a Fresh Roast 8 can roast batch in 4 minutes, but by simply throttling, I can make the roast last 12 minutes.

John


John, I know this post was eons ago, but I'm new and wonder: What is 'Throttling' a FreshRoaster?
 
John Despres
Top  #14 Print Post
Posted on 03/10/2011 8:09 PM
Hi, Randy. Welcome aboard!

"Throtling" is dialing the timer back to cool for a few seconds every 30 seconds or so, and then back up to heat.

The idea is to keep the cool stage very short so as to not drop the bean temperature thereby stalling the roast.

Throttling will stretch the length of the roast.

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
Jimbo
Top  #15 Print Post
Posted on 03/12/2011 8:52 AM
Great thread, with great info. I got a Behmor a few months ago, and initially was having a real rough time with it. I got no transition between first and second ... none! I've played with it and am still experimenting, but have gotten a better delay.

The initial roasts were less than promising. But selecting the right profiles, and cracking the door a bit after first crack have help to slow the transition.

On my Hottop (non-programmable model) I consistently get 1 - 2 minutes between the cracks, depending on the bean. Not much I can do with the Hottop since I don't have very much control. But the roasts are always consistent.
"You do realize that your detailed plan has three steps and two of those steps hinge on running?"
 
Indiana Randy
Top  #16 Print Post
Posted on 03/12/2011 2:05 PM
Thanks John!

Next roast batches, I'll be Throttling! LOL

Right now, I have a good week of coffee to drink before I start making more. Plus I got a shipment of 9 pounds of different coffees from Burmans..... Oh the choices.... Grin
 
JETROASTER
Top  #17 Print Post
Posted on 02/01/2012 2:42 PM
Ok,... dragging this thread back out.
The stretch between 1C and 2C; Is there anything that would suggest this 'rule' is the same for drums and fluidbeds?
I guess the question is whether or not it is a bean thing, or an energy delivery thing?

I hope I'm making sense....it's not always the case.
Thanks, -Scott
 
endlesscycles
Top  #18 Print Post
Posted on 02/01/2012 5:48 PM
people actually go to 2C? nasty.
-Marshall Hance
Asheville, NC
 
ajrunningbiking
Top  #19 Print Post
Posted on 02/01/2012 7:37 PM
Interesting thread, old, but interesting. I am roasting my first Harrar and am struggling dialing in the roast. The beans just don't seem to react the same as the Central American's I usually roast. Totally drinkable, but nothing special.

My thought is to be more aggressive in the first stage prior to first crack and be somewhat aggressive between 1 and 2 C. Though I never go to 2 C.

Anyone have any insights into roasting Harrars?
 
mk1
Top  #20 Print Post
Posted on 02/01/2012 10:57 PM
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
 
JETROASTER
Top  #21 Print Post
Posted on 02/02/2012 8:12 AM

Quote

ajrunningbiking wrote:
My thought is to be more aggressive in the first stage prior to first crack and be somewhat aggressive between 1 and 2 C. Though I never go to 2 C.

Anyone have any insights into roasting Harrars?


Sounds good to me. I would go pretty light on Harrar as well, quick seems to work better(air-roaster).
Please remind me what you are roasting with? -Scott
 
ajrunningbiking
Top  #22 Print Post
Posted on 02/02/2012 10:37 AM

Quote

freshbeans wrote:

Quote

ajrunningbiking wrote:
My thought is to be more aggressive in the first stage prior to first crack and be somewhat aggressive between 1 and 2 C. Though I never go to 2 C.

Anyone have any insights into roasting Harrars?


Sounds good to me. I would go pretty light on Harrar as well, quick seems to work better(air-roaster).
Please remind me what you are roasting with? -Scott



Hey Scott - I am roasting with a home built air roaster.

I am going to do another sample roast this weekend with the goal being to start aggressive then start to slow down past 1C. I am thinking the roast length maybe 10 mins to 10.5 mins with this plan.
 
seedlings
Top  #23 Print Post
Posted on 02/02/2012 12:00 PM
for my roaster I like the harrar:
4min to 300F
4min more to 390F
1min or so blast the heat till 410F
3min stretch cruise to 425F

Dump, cool, rest for 3 days or so.

CHAD
Roaster: CoffeeAir II 2# DIY air roaster
Grinder: Vintage Grindmaster 500
Brewers: Vintage Cory DCU DCL, Aeropress, Press, Osaka Titanium pourover
 
jedovaty
Top  #24 Print Post
Posted on 02/02/2012 1:53 PM
I read through Boot information, thank you, that was helpful. I'm a bit confused, however, on some of the theories and discussions here. It appears that if you left the roaster untouched, then shortly before 1st crack, bean temps should start to flatten out, and assuming a constant heat source with enough power to prevent BT from dropping, about half-way through FC the BT would begin rising again. This is without touching the heat source's power (leaving it constant). Is this correct?
 
JETROASTER
Top  #25 Print Post
Posted on 02/02/2012 3:36 PM
...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
 
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