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Topic: Gene Cafe Update (132 lines)
1) From: Steven Van Dyke
Ok, after my 4th roast in my Gene Cafe I think I'm getting the hang of it=
.
 The first three roasts weren't too bad but definitely needed work.
Took me into the second roast to figure out that, even though the Gene Ca=
fe
is a *very* quiet roaster, I have trouble hearing first crack with it. 
I think it's because the sound of the beans rolling and tumbling sounds
too much like first crack (at least to me).  Now I know to keep my ear do=
wn
near the gap in the front - the 'safety shield' also blocks some of the
'crack' sound.
On my third roast I tried 'sneaking up' on the roast level I wanted.  I
at least succeeded in not overshooting but I may have ended just a *touch=
*
light.  That El Salvador Finca El Carmen is *good* coffee though!
Last roast was the Ethiopian Dry Process Ghimbi.  It's still resting but
starting to smell really nice.   I think I hit this one right on target.
Working from my notes, here's how it went:
Roasted out in our sunroom, screens open for ventilation and fan running
to keep the air moving.  Ever-indulgent wife and one cat observing with
amusement (cat the whole time, wife got bored and wandered off).  Ambient=
temperature 87F.
Loaded 250 grams into the drum and set the unit for 482F / 18Min (recomme=
nded
start and it's working so far).  My plan was to drop the temp setting to
454F when I hit first crack to reduce the chance of overshooting the Full=
City Tom recommends for this bean.
By comparing the color and look of the beans with Tom's roasting guide an=
d
the displayed exit air temperature I determined that there is somewhat of=
a lag between the exit air temperature and the bean mass.  Looks like the=
beans run about 80 - 100 degrees behind the exit air in the earlier stage=
s.
 Takes time for the beans to absorb the heat but eventually they do catch=
up.
By listening down at the 'gap' under the safety shield I was able to catc=
h
First Crack.  Bean color told me when I was getting into the right area
to start listening.  I *could* run the roaster with the safety cover open=
but I think that would cause some heat loss and I'm trying to establish
a simple enough baseline my ever-indulgent wife can roast in an emergency=
.
Heard First Crack starting about 10.5 minutes into the roast.  Exit air
temp was showing at 456 which you'll recall is the temperature I was plan=
ning
to drop to from my 482 start.  Dialed the temp down to 456 so the unit wo=
uldn't
try to take the beans up past it.  Started watching the chaff collector
exhaust for the first hints of visible smoke - that's always a good indic=
ator
that you're coming into Second Crack, at least in my experience. 
Saw a puff of smoke and hit the COOL button at 14.7 minutes into the roas=
t.
 Let it cool all the way to 140 in the machine (again, I'm trying to esta=
blish
my baseline).  Took about 11 minutes, then I dumped the still warm (140F)=
beans into a large wire strainer and finish cooled them in front of the
fan.  Being a dry processed Ethiopian there was a fair amount of chaff,
a lot of which was still stubbornly clinging to the beans, at least until=
I started stirring them in front of the fan.  The resulting chaff storm
chased the cat out of the room.
Speaking of chaff, I pulled the chaff collector off toward the end of the=
cooling cycle.  Didn't do it to speed the cooling, although that helps.
 I did it so I could go outside and empty it and be back in before the sh=
ow
I wanted to watch came on.  *Lots* of chaff in the collector.  The 'swipe=
r'
on the exit did a pretty good job of keeping up with the chaff during the=
roast.  On one half of the cycle the door is swinging 'down' and lays clo=
ser
to the screen giving it a good wipe.  On the other half gravity is pullin=
g
the swiper away from the wall and it leaves a bit of chaff behind.  That
flexibility is also part of why it only 'clunks' on one half of the cycle=
.
Overall I believe I wound up with some really nicely roasted coffee.  Pre=
vious
batch looks like it's going to run out right as this one finishes resting=
so I'll know for sure in a day or so.
Oh, one note for you drum roaster builders:  The off-axis rotation produc=
es
an *amazingly* even roast.  The 'vane' design is pretty simple too - just=
the one in the center with the holes / deflectors at each end.  For a non=
-hot
air heated drum you don't need the 'swiper' so it's a really easy design.=
 Works great at slow rotation speeds such as the slow turn of a 'stock'
rotisserie unit for most grills.  Might be worth it for one of you to try=
making a drum with spit holes arranged to make the drum hang at as much
of an angle as possible to the spit rather than shooting for perfectly ce=
ntered.
Enjoy!
Steve :->http://www.cafepress.com/stevespics<- My little store of Impressionist">http://www.svandyke.com<- My simple websitehttp://www.cafepress.com/stevespics<- My little store of Impressionist
& Special Event photography


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