Gene Cafe Profiles / Q&A / Tips & Tricks

[BoldJava]

Someone finally blinked.  The Gene Cafe has been reduced in price at one site, $429.  It took 6 months of the Behmor sitting out there at $300 to pull the Gene down in price.   I am a bit surprised that it took that long.

http://www.coffeewholesalers.com/genecafe.htm

B|Java

[BoldJava]

Gene Roast thread:  Forgot what it was like to roast with the Gene after months on the Behmor.

Gene set-up:
^  Large chaff catcher, vented out kitchen window with alum flex-duct (use shop vac after every 2nd roast to pull chaff from catcher)
^  Fan in window, exhaust - http://xrl.us/WellHoney (Link to www.target.com)
^  Roasting under kitchen vent
^  Kitchen full of roasting aroma, some smoke, but odor not moving thru house.  We'll see what Czarina thinks when she comes home...

Profiles:
^  Pre-heat unit to 360
^  Roast 220g, 8 ounces
^  High growns, 480 to 15 seconds into 1st, => 460 to edge of second
^  Brazils, 470=>455
^  Konas, have to dig thru my notes

Stuck by:
^  Value of the visual.  Makes me realize how 'eyeballing' is important to me and miss it when using the Behmor

Why the Gene today?  Behmor is not coming thru for me on larger beans.  Miss the visual cues that Gene offers.  Trying to tame the Gene odor in prep for Winter roasting.

B|Java

[Pyment]

my newest profile. I have based this on the profile used at the SCAA roasting class:

I have done this with preheat and without - about a 30 sec difference in time to 1st crack.  No difference in flavor that I can pick up.

480 to 1st crack.

at 1st crack reduce to 427 at start of 1st crack, pretty much letting exothermy carry it most of the way through first crack. If it slows too much, raise to 431

2 minutes after start of first crack increase to 437 for a city to city+. 440-450 for a darker roast.

finish at 16-18 minutes depending on degree of roast and how long I want to stretch the time after first crack.

My last roast a person I served it to asked if this coffee was hazelnut flavored. I definitely got hazelnut, pear, chocolate. I still feel the heater is underpowered, but still responsive. Most of the concerns here relate to slow ramp to fc and poor cooling.

[BoldJava]

Dialing in the best roast. Gene Cafe

Been reading B|Whiskers insights on roasting and kicking the can with Peter.  Trying to fine tune and learn more, particularly since I have gone back to the Gene and have visuals and more control with temp. 

Took a bean with which I am familiar (Bol Nakhaki general farm) and roasted it four ways, in succession, all to the edge of 2nd crack (FC).  Began each roast with a pre-warmed Gene to 350F.  Cupped each today, using same prep (Yama).  Interesting results.

Temp is merely reading (setting) of external heat read, not mass temp.

Roast 1: flat, dull, 'listless' cup.  Didn't resemble a Nakhaki
^  350:  0-2:00
^  480:  2:01-5:44
^  458:  5:45-7:45, yellow stage
^  480:  7:46-11:30, 1st crack at 10:45)
^  471:  11:31-14:45, no second

Roast 2: sharp edge, lacked sweetness I associated with the Nakhaki; not a developed flavor-spectrum.  Moves towards a sharp edge.
^  480:  0-12:55 (first crack at 9:30)

Roast 3:  Oh, now this is the Nakhaki.  Lightly chewable, nice caramel going on.  I visualize a smile or saucer shape to the taste.  Great cup.  Phew.  Dramatic taste difference with a minor tweak.
^  480:  0-10:19 (first crack at 9:35)
^  471:  10:20-13:25

Roast 4:  Good cup but not as 'wide' as roast 3.  Narrower horizontal tastes.  Flattened the cup compared to the 3rd roast.
^  480:  00-10:35 (first at 9:50)
^  460:  10:36-13:45

[peter]

What a cool experiment!

So the one you liked simply had the heat turned up and stayed up, right into 1st, and then heat was turned down for a coast?

[BoldJava]

What a cool experiment!

So the one you liked simply had the heat turned up and stayed up, right into 1st, and then heat was turned down for a coast?

Not sure about 'coast' but minimally lower.  I learn by doing and reviewing.  Having this experience cements the learning in for me.  I could have read this from others and it wouldn't register in the way this has.

Good exercise.  Will tweak my roasts going forward, noting growing elevation and making adjustment in initial setting.

B|Java

[peter]

What a cool experiment!

So the one you liked simply had the heat turned up and stayed up, right into 1st, and then heat was turned down for a coast?

Not sure about 'coast' but minimally lower.  I learn by doing and reviewing.  Having this experience cements the learning in for me.  I could have read this from others and it wouldn't register in the way this has.

Good exercise.  Will tweak my roasts going forward, noting growing elevation and making adjustment in initial setting.

B|Java

What I'm reading is the batch you like the most had virtually zero profiling, right?  Turn the heat to set point, and let the heat work its magic.

[BoldJava]

What I'm reading is the batch you like the most had virtually zero profiling, right?  Turn the heat to set point, and let the heat work its magic.

I am not biting.   Dangle the worm, chum the water, flick the jig.  No bites.  High-priced <im>poster if I have ever seen one.

B|Java

[Jeffo]

Man this is complicated stuff.

[peter]

Man this is complicated stuff.

It is complicated.  I'm baffled; there was an honest question, and now B|Jiggler's talking about fishing.  I'm clueless.

[donn]

It is complicated.  I'm baffled; there was an honest question, and now B|Jiggler's talking about fishing.  I'm clueless.

I'm guessing by your question that you're in possession of some ideas about possible useful ways to vary temperature prior to 1st crack?  I can't use numbers (I'm sort of butting in here, since I don't actually have a Gene roaster), but I'd love to hear some general early profile principles.

[BoldJava]

I'm guessing by your question that you're in possession of some ideas about possible useful ways to vary temperature prior to 1st crack?  I can't use numbers (I'm sort of butting in here, since I don't actually have a Gene roaster), but I'd love to hear some general early profile principles.

Donn, there is good material re:  your question here:

http://www.greencoffeebuyingclub.com/index.php?topic=3679.msg51269#msg51269

B|Java

[Pyment]

After taking the SCAA's intermediate roasting class and my class with Victor Mondry. I have come to this kind of thinking:

482 to the start of 1st crack. This is to minimize time to 1st crack. I am getting FC in about 12 min. without preheating.

dial back to 429-31 to slow the roast and let the exothermy of first crack take it for about 2 minutes.

after 2 mins, in the late portion of first crack, I increase to 437 for a city+ roast and 440 for a full city or beyond.

I am trying a new twist. I accidentally left the cover off the chaff collector for the first 5 minutes. Interestingly, the measured air temp increased faster due to improved air flow. Then I put the cap back on and continued as usual. The time to first crack was the same. I am just drank a city+ Yerg roasted in that fashion. It is dynamic with great brightness (too much for my wife).

I can't measure bean temp but I suspect that it lagged air temp more than usual with a faster ramp in the latter portions of the ramp to first crack. This had the effect of preserving the brightness better than the usual roast.

[BoldJava]

After taking the SCAA's intermediate roasting class and my class with Victor Mondry. I have come to this kind of thinking:

482 to the start of 1st crack. This is to minimize time to 1st crack. I am getting FC in about 12 min. without preheating.

dial back to 429-31 to slow the roast and let the exothermy of first crack take it for about 2 minutes.

after 2 mins, in the late portion of first crack, I increase to 437 for a city+ roast and 440 for a full city or beyond.

...

I have plenty of the Nakhaki field grade bean.  I will try your profile, side by side with my favorite from this past week, and see which cups better for me.

How quickly into 1st are you dialing back?  Immediately?  My concern with your profile is that it would seem to make sense with a 20 kilo drum roaster.  I am unsure how much heat is truly built up in an 8-9 ounce mass of coffee in an air-drum hybrid like the Gene.

But then again, I stunk up the class in physics.  I will give it a fair taste test.

B|Java

[Pyment]

I have used this process at Victors with a 250 gm sample roaster. at the SCAA we roasted 2 lbs on an IR3. In both settings we turned it back to where the flame is lowest. I think the drum on the sample roaster has more relative thermal mass and is better insulated which is why I left the temp as high as i did. The Gene is underpowered and has too much air contact at the outside of the drum. My suspicion is that the drum is cooler than the grate. I wish the plastic cover covered more of the drum to help maintain temp. But then you might reach temps that would melt the plastic. A more robust material would probably raise the cost.

I was thinking that the thermal mass was going to be a problem and did find it was when I dialed back to 410. Dialing back to 429, the minimum air temp will be 422ish which is still above the temp where 2nd crack usually ends. I get a first crack that lasts about 3 minutes.

I wait until I feel 1st is underway (this usually means the pops occur in groups - about 15-30 secs after 1st pop usually). Then after 2 mins of first when it is starting to slow I turn it up to my final temp.