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Topic: trier question (9 msgs / 345 lines)
1) From: Peter Zulkowski
Please forgive me, but I do not understand the need for a trier.
Just from my experience, having never watched anyone else roast, it 
seems like the beans roast along just fine for the first 10 minutes or 
so, then towards the end of the roast, in the last few minutes, the 
degree of roast changes very quickly, just a few seconds between city 
and full city for example.
The roast finishes so quickly that I myself would not be able to sample 
any with a trier without it going on to the next stage of development.
What am I missing here?
I can take a few minutes between first and second crack, but I mostly 
pay attention to thermocouple readings to get my degree of roast.
Please help, I am sure there is lots more I need to learn about roasting 
coffee.
PeterZ
On the computer today,
Here in Danvers, MA

2) From: Tom & Maria - Sweet Maria's Coffee
Well - you are right, at the end of the roast you are using a trier 
quite rapidly to check the degree of roast. But the benefit of a 
trier is huge - there is nothing like being able to pull out some 
coffee, really look at it, smell it etc while it is not moving. I 
have thought that there might be a differnt manifestation of a trier 
- what if you had a little tube that diverted a sinle stream of 
coffee from the roaster and passed it in front of the roaster 
(person) at a slow rate so it could be observed. You could do that 
even with a roaster like the Alp (totally covered, no peeking) and 
still knowexactly where the roast was at.
Tom
<Snip>
-- 
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
                   "Great coffee comes from tiny roasters"
            Sweet Maria's Home Coffee Roasting  -  Tom & Maria
                      http://www.sweetmarias.com                Thompson Owen george
     Sweet Maria's Coffee - 1115 21st Street, Oakland, CA 94607 - USA
             phone/fax: 888 876 5917 - tom

3) From: Oaxaca Charlie
--- Tom & Maria - Sweet Maria's Coffee
 wrote:
<Snip>
 Plus-with a trier you can keep samples of beans pulled at
different temps to cup later, helping you learn what your
favorite roast for a bean looks like when ready, as well as
what temp is likely to be showing on your thermometer when
it's time to dump and cool the roast..
  Charlie (wishing I had a trier)
<Snip>
<Snip>
                                         Oaxaca dreamin'
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around http://mail.yahoo.com

4) From: Jason Molinari
<Snip>
HOLY CRAP! I never thought of this! I have a trier on
my mini drum, and i use it sort of just to see how the
roast is developing...i never thought of keeping a
sample from a few different roast levels to be able to
taste the differences without roasting multiple
samples! BRILLIANT!!!!
jason

5) From: Michael Wascher
A coffee roaster in Ohio used to use the trier in the early stages to 
measure the bean's' specific mass. They took a volume of beans and weighed=
 
them before the roast. 
As the roast progressed they pulled samples, weighed the same volume. Once=
 
they got close there wasn't time to weigh -- they used sight, smell & sound=
 
to decide when to dump.
After the roast was over there was a last weighing. The change in specific=
 
mass was their QA. The owner said it was the best & most precise indication=
 
of degree of roast that they had.
--MikeW
On 9/13/05, Jason Molinari  wrote:
<Snip>
-- 
"Not all things that are countable, count, and not all things that count,=
 
are countable". Albert Einstein

6) From: Peter Zulkowski
Thanks Tom and Charlie!
Looks like I need to adapt a trier to my PGR.
PeterZ
Camping on the ocean in Gloucester, MA.
Oaxaca Charlie wrote:
<Snip>

7) From: David B. Westebbe
<Snip>
You're missing a couple of things:
In big commercial roasters, the degree of roast changes MUCH more
slowly.  You've got a lot of mass to heat up, and unless you are
supplying HUGE amounts of Btus, that takes time.
The other thing is that the speed of change varies, and depends on the
temperature differential between the hot and the cool substances.  So if
your heat source is close to what you want your final bean temperature
to be, you will not get a quick change near the end, but rather, a slow
change.
In fact, I try to set my air inlet temperature to just slightly higher
than what I want my final bean temp to finish at.  That way, I can hold
the beans at the optimum temp for a while, ensuring that they are all
heated evenly, and that they are heated to their core to the proper
temp.
Imagine a worst case scenario, with your air temp VERY high.  You will
get beans that are like a medium-rare steak, with the outside charred
and the inside almost raw.

8) From: Peter Zulkowski
This is a multi-part message in MIME format.
Hi David,
Thank you very much for your reply.
I had thought noticed with a souped up air popper that I was scorching 
beans, so I controlled it with a variac, but still it was out of control 
because I could move a thermocouple around in the beans while roasting 
and get widely varying temperature readings.
With my PGR the Turbo Oven sits on top, and I measure the temp at the 
bottom of the swirling beans, well, below the top anyway. Frankly, I 
have no idea what the air temp is coming out of the turbo oven, just 
figured it is high enough above them so scorching is not an issue.
Thank you for jolting me into realizing that I really need to check that 
temp and keep the air just above what I want the final bean temp to be. 
At last! A reason to PID my PGR!
Somehow I wanted to do that, but your suggestion got me thinking about 
it and motivated.. more to come....
I just HAVE TO keep this roaster whole, so I will build another... 
bigger... better... prettier ;)
The beans do roast very evenly, and the roast is controllable, I mean, I 
can delay the total time. It is just that I thought I was observing the 
exothermic part of roasting that was racing through the end.
I cut the heat just after first crack, maybe nudge it a bit, and 
suddenly just before second crack the temperature takes off! Perhaps the 
heating element is getting much hotter than I want it to be, and that is 
causing this problem. I usually take a couple of minutes between first 
crack and second. That just doesn't seem very long. Total roast time is 
less than 15 minutes.
What kind of roaster do you have?
PeterZ
Still learning about roasting, here in Gloucester and everywhere.....
Smile..
David B. Westebbe wrote:
<Snip>

9) From: David B. Westebbe
This is a multi-part message in MIME format.


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