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Topic: New profile experiments -- not by time/temp but by (11 msgs / 292 lines)
1) From: AlChemist John
Sometime around 20:40 8/8/2003, HeatGunRoast typed:
<Snip>
I like this kind of train of thought.  Very open, flexible and produces a 
good cup.  I can imagine when I first started roasting though, it would 
have been to vague.  Good for the seasoned roaster (person).
<Snip>
I am not sure if I started the term, but I have spoken of "pushing" the 
ramp and playing catch-up.
<Snip>
I think this is a great idea.  This is how I tend to roast, but I have 
never taken a written note so direct comparisons are difficult.  I would 
recommend recording final time and temperature but not use it along the 
way, otherwise comparisons may be difficult.
Also, I recall smell being used by some people.  I have general used it but 
for the last week or so have stopped my roasts completely by smell.  I have 
cooled my roasts at the point where the smell turns from slightly acrid 
(pre 2nd crack) to a touch sweet.  So far it has been between 435-455 and 
the roasts have been fantastic.  Might be a reasonable indicator for the 
"sweet spot" on a  particular roast/bean.  So far, it has worked on two new 
beans.  I will see if it continues to work.
--
John Nanci 
AlChemist at large
Zen Roasting and Blending by Gestalthttp://www.dreamsandbones.net/blog/

2) From: Barry Jarrett
At 06:19 AM 8/12/03 -0700, you wrote:
 >cooled my roasts at the point where the smell turns from slightly acrid 
 >(pre 2nd crack) to a touch sweet.  So far it has been between 435-455 and 
 >the roasts have been fantastic.  Might be a reasonable indicator for the 
 >"sweet spot" on a  particular roast/bean.
i always roast a new bean by smell, and use smell as a verifier of other
indicators (bean temp, sound, etc).  if i have to roast electronically
blind (no temp readout), smell becomes the primary means of selecting
endpoint.  for all those years before i put in a temp probe, smell was It,
and It worked quite well.  while not quite as consistent as the techophile
methods, the results were always quite good.

3) From: AlChemist John
I know a lot of people state they use smell (as you do) but not how.  What 
cues in the aroma tell you where you are in the roast profile.  That is the 
descriptive I was trying to address.
Sometime around 07:37 8/12/2003, Barry Jarrett typed:
<Snip>
--
John Nanci 
AlChemist at large
Zen Roasting and Blending by Gestalthttp://www.dreamsandbones.net/blog/

4) From: Tom & Maria (SweetMaria's Coffee)
<Snip>
For me the sweetening of the roast smells is starting as the coffee 
prepares to go exothermic  (which seems like it would be the 
opposite, and you would have more sense of roast aromatics when the 
roast is exothermic). Maybe its because I don't smell the coffee as 
much when it is popping under my nose - it just seems dangerous, and 
I have to admit the very hot trier metal and my face have kissed a 
few times, leading to a very difficult-to-explain 2nd degree burn. So 
around 380 roughly is when I start sniffing the sweetness, and coffee 
seems less grainy in aroma. probably at 420 I start smelling again, 
noting the pungency. I also look for increased steam-smoke off the 
coffee as it reaches the verge of 2nd crack. All this is possible 
with a trier on a drum roaster, and is one of the things sadly 
missing from home roasters. Did anyone look at the Honduras Cupping 
page I made with the small electric colombian roaster? That has a 
trier ... very cool. Its also on the new Roaster Picture Page I 
made...
Tom
--
                   "Great coffee comes from tiny roasters"
            Sweet Maria's Home Coffee Roasting  -  Tom & Maria
                      http://www.sweetmarias.com

5) From: Ken Mary
<Snip>
For drum roasters, the best and easiest method is a thermocouple or
thermometer probe buried in the bean mass. Just make sure the probe has low
mass so the delay in response is short enough that you can deal with it.
Hot air roasters may be better off with an IR thermometer. Some precautions
must be taken to keep the hot air stream away from the thermometer since the
beans must be directly visible.
Hot air passing through the beans will cause a direct reading probe or
thermocouple to deviate from the actual bean temp, and this effect varies
with the amount of airflow.
Just remember that you are measuring the temperature of a small portion of
beans, and that may not be representative of the whole mass. Even an IR
thermometer sees only the visible surface of the beans within its spot
diameter.
--

6) From: David Lewis
At 5:54 AM -0700 8/13/03, AlChemist John wrote:
<Snip>
Hi John,
After first ends, there's a somewhat acrid, maybe phenolic, smell. 
Barry has described it as "grabby" in that it grabs your nose. Rather 
suddenly, that will smooth out and start to smell sweet. I think 
that's probably the earliest one should stop a roast for most brewing 
methods, and it seems to maximize varietal character. Decafs are even 
more clear: they really stink until that point.
Best,
	David
-- 
"A designer knows he has achieved perfection not when there is 
nothing left to add, but when there is nothing left to take away."
Antoine de Saint-Exupery

7) From: Barry Jarrett
At 10:59 AM 8/13/03 -0700, you wrote:
 >roast is exothermic). Maybe its because I don't smell the coffee as 
 >much when it is popping under my nose - it just seems dangerous, and 
 >I have to admit the very hot trier metal and my face have kissed a 
 >few times, leading to a very difficult-to-explain 2nd degree burn.
mustache!  it's saved my upper lip more than once....   :)
 >coffee as it reaches the verge of 2nd crack. All this is possible 
 >with a trier on a drum roaster, and is one of the things sadly 
 >missing from home roasters. 
the very first time i saw the alp at the int'l housewares show (years ago)
and the guy wanted to know what i thought, i said, "needs a tryer."  they
promised a "semi-pro" model was in the works, with a tryer and window.

8) From: Barry Jarrett
At 05:54 AM 8/13/03 -0700, you wrote:
 >I know a lot of people state they use smell (as you do) but not how.  What 
 >cues in the aroma tell you where you are in the roast profile.  That is the 
 >descriptive I was trying to address.
it's not so much a particular smell, as a shift in smell.  it's very
difficult to describe, although tom did a good job, and is better learned
firsthand.
for me, coffee "before it's done" has a very sharp, acrid aroma.  it will
smell like all sorts of things (wheat, bread toast, etc) but always there's
this background "edge".  it sort of grabs me right behind the eyes.  right
around 2nd crack, sometimes just before, sometimes just into, this
sharpness goes away (quickly), and the aroma fills out and smooths out.
i've sometimes described it as "blossoming".  when this happens, the aroma
doesn't poke the inside of my head quite the same.  roasting further will
change some of the character of this smell, allowing it to smooth out even
more, until it reaches a point where it gets sharp again around 1st oil.  
sometimes, for coffees like yemen or harrar, where there are distinctive
aromatics, i roast until they start to emerge.  the cedar smell changes to
berry or chocolate...
and decafs... well...  i roast 'em 'til they don't stink anymore.  :)

9) From: David Lewis
At 6:19 PM -0700 8/16/03, Barry Jarrett wrote:
<Snip>
Any particular reason a tryer has to be made from metal? There are 
lots of other materials that would take the heat, not outgas and 
affect the coffee, and have high enough thermal resistance that if 
your lip touched the tryer at roasting temperature you would not be 
burned.
Best,
	David
-- 
"A designer knows he has achieved perfection not when there is 
nothing left to add, but when there is nothing left to take away."
Antoine de Saint-Exupery

10) From: David Lewis
At 6:27 AM -0400 8/17/03, Ron wrote:
<Snip>
Well, it would have to be something slightly exotic, since we're 
talking about temperatures in the 600 F range. So I was thinking of 
a ceramic of some sort, like maybe alumina, which should be available 
in a tube. Carbon-carbon would probably work too, except that it's so 
dangerous to shape if you're not very careful. The materials would be 
a bit spendy, but since you'd be using only a little it still 
shouldn't be too bad. When I privately spoke to Barry about this, I 
mentioned a gee-whiz picture I'd seen in the seventies, when I was 
peripherally around the space shuttle program: the insulating tiles 
were an alumina formed under high heat and pressure, so that they 
were in a crystalline state. They had been heat-soaked at 1200 C for 
five hours, then removed from the oven. They were far enough into 
white heat that the picture had been taken solely by the light of the 
glowing tiles. Their thermal resistance was so high, though, that the 
engineer was holding them in his bare hand and not being burned.
Best,
	David
-- 
"A designer knows he has achieved perfection not when there is 
nothing left to add, but when there is nothing left to take away."
Antoine de Saint-Exupery

11) From: AlChemist John
Sometime around 21:46 8/28/2003, David Lewis typed:
<Snip>
This sounds a lot like platinum crucibles I use in the lab.  They come out 
of the 600C furnace glowing fiercely and you can pick them up in 
seconds.  I almost wet myself the first time I saw it done.  I was sure we 
had a third degree burn emergency in the making.  I have always attributed 
it to a  very low heat capacity.  I have never heard of thermal 
resistance.  Regardless, a platinum tryer would definitely be exotic!
<Snip>
--
John Nanci 
AlChemist at large
Zen Roasting and Blending by Gestalthttp://www.dreamsandbones.net/blog/


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