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New Gene Cafe thoughts
John Despres
Top  #1 Print Post
Posted on 11/01/2010 9:32 PM
Okay, I've been playing and getting some awfully darn fine roasts out of my Gene Cafe.

I have a slightly low 116-117 volts power in the roasterie. That's a dedicated circuit and about 4 feet from the breaker box.

The time from cold to 482F will indicate what kind of profiling you might use in the Gene Cafe. Mine goes from cold to 482F in about 6:30 while a friend's does it in about 4:00. I cannot use his profiles.

The approach I'm using now is a bit like Sweet Maria's Tom Owens suggestions that come with the roaster.

First off, I believe in preheating the drum, so I do. Every set of numbers I choose depends on the bean and the target degree of roast. In general, after a through vacuum of the drum, air passages and the chaff collector, I preheat to 400F for 3 minutes. Any less time doesn't preheat the machine and a lot of heat will be lost when I add the beans. I typically lose about 50F even though the beans are prepared and ready for the drum, no mater how quickly I load the drum.

Once the drum is returned to the roaster, I set the high at 455F to 465F depending on the bean. I can't remember where I read it, but I shoot for yellow at about 5:00. First crack will typically come between 10:00 and 11:30. I'll drop to 435F to 445F (again, depending on the bean) between the onset of first and :30 into first, then end the roast a I see fit, depending on target roast sometime after the end of first.

I haven't eliminated the drying stage, but have altered it to fit my roaster and somewhat weak power supply.

I'm producing some pretty darn fine coffee and enjoying every drop. Yesterday morning I roasted my first batch of Ethiopia D-P Jimma. By all indicators - smoke aroma, sight, sound, roast aroma and appearance, I think I have a pretty nice roast.

Softer beans get a more gentle preheat and perhaps a high setting of 455F. SHG/SHB get higher numbers. The rest of my decisions are based on target degree of roast and bean type. I look over Tom's notes almost every time I roast and make my choices then. I keep notes and make adjustments as I see fit.

Have fun.

John
Edited by John Despres on 11/01/2010 9:32 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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smatty1
Top  #2 Print Post
Posted on 11/02/2010 7:14 AM
Interesting. I'll try that out on my roasts this week. Can you say a little bit about the reasoning behind the 445-455 top temp as opposed to a 476 -482? Body developement? Smoother roast profile?, etc....
 
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John Despres
Top  #3 Print Post
Posted on 11/02/2010 7:44 AM
Smoother and a bit more gentle attack. If you want to slam on the brakes at around first crack, it's a bit easier to do it at 150 MPH than it is at 350 MPH.

With the preheat, you may not make it to your set high, anyway. First may come at ET of 438F.

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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Marshall_S
Top  #4 Print Post
Posted on 11/02/2010 10:01 AM
I've tried John's profile on a couple of roasts over the weekend and had some great results. I notice that there is no edge or bite whatsoever and the flavor seems even more pronounced. I assume this is due to ramping up more quickly and keeping the heat down to 465/444. Let's hear from some other Gene Cafe roasters on this - I think John has really got something here! ThumbsUp
Marshall Schmidt
Foxboro, MA
 
RichC
Top  #5 Print Post
Posted on 11/02/2010 11:58 AM
Well, I haven't used John's approach yet, but did do a bit of a change on my last roast due to some info gained at GCBC. My general profile consisted on a preheat, 482dgf for 8 minutes. I use a variac to keep voltage at 120v-121v. Dump beans, then use a drying phase of 5 minutes at 300-341, followed by a ramp-up of 5 minutes to 435dgf-445dgf, then a rush to FC using 474dgf-482dgf. As FC would happen, I would reduce temps anywhere from 462dgf to 470dgf, bean dependent. This general profile had served me well for the last 10 months, and about 70 roasts.

But the last roast of Amaro Gayo was missing the blueberry bomb that I associate with that bean. After asking a few cohorts at GCBC, I decided that I might be taking to long to get to FC. FC after the drying, ramping, then rushing was taking about 12+ minutes, and they were not turning yellow until 7-8 minutes. I adjusted the profile to 8 minutes of preheat at 482dgf, followed by 474dgf until FC + 45 seconds then 468dgf until end-of-roast(EOR). FC happened at 10:30 and EOR was at 12:45. I was hoping for a city (~2:15 to 2:30 minutes following FC), and that's what I got. What I also got was the blueberry back in my AG. Wow was it back.

I am using a different profile that Boldjava gave me for the Hawaiian beans and Island beans I have been roasting, and I have been very pleased. Regular preheat (482dgf/8 minutes), add beans then 341dgf for 5 minutes, increase temp to 467dgf until FC, and EOR comes at 2:45-3:00 following FC. This skips the ramp-up phase. I have used this the past 4 hawaiians ( 2-Kona's and 1-Maui Mokka, and 1-Ra'u) I have done, and have loved them all, to the very last drop.

I am going to experiment with a shorter preheat, and a lower temp. I think the carafe gets so hot there is some scorching when the beans are dumped. BTW - my preheat time from cold to 482dgf with variac at 120v is 6.0minutes, without variac and house voltage of 117v, around 6.6 minutes. I have found the Gene to be very, very voltage dependent.
Gene Cafe, Kyocera Hand Grinder, Baratza Vario, Aeropress
 
ahedges
Top  #6 Print Post
Posted on 11/02/2010 3:40 PM
I've been doing similar to what John described. Higher preheats, and a faster ramp up to first. I've really been liking the results. A lot more flavor pop in the cup. I have been preheating to 350. Then dumping beans in and heating at 350 for 5 minutes though (drying). Then setting higher temps. (471, 465, 456 depending on the bean.) After first i am dropping to the 440's (again depending on the bean). After reading this post this morning, today being roast day, I went ahead with a 400 preheat and lower initial temps. I was surprised that 1st came faster than normal but still appear to have hit my target at least 1 out of two. (the first roast (Equador Especial) came out quite uneven and looking a little funky) We'll see how they taste. It has been my experience that John's application of roast theory to the Gene Cafe is pretty darn good.
 
Third Crack
Top  #7 Print Post
Posted on 11/03/2010 6:57 AM
I am very new at this so I'll just make some general comments. I modified my Gene to run the heater off a variac. Not so much because of low voltage (although my line voltage is a little low so it is helpful there too) but to give even more flexibility for profiles. My early thought is that it will not be so helpful for hard beans. In general it seems that you can give full power to hard beans which is what the Gene does until you get to a set point. My best run so far was to preheat to 375, immediately ramp at 120 volts to 465-470 exit, drop to 110V to maintain the 465-470, drop to 95V (about 445 exit) at first crack. If this sounds a lot like John Despres' profile it is no surprise since I have watched his work closely. I hit yellow in about 4 minutes and first crack in about 9 minutes and dumped at 12 minutes at about City+.
I think my modification will be more interesting to compliment procedures for softer beans where you may want to ramp at a lower voltage or use different power at different points. I probably will be working with hard beans for the time being so I won't know. Right now I want to concentrate on the best ramp speed (I am thinking full out at 120V), the optimum high temp (probably in the 465-475 range) and the secondary voltages to gain control of the first crack and beyond trying to get about 3 minutes from start of first crack to dump (whether it be City to Full City). I will post anything significant if I ever find anything! Bob
 
smatty1
Top  #8 Print Post
Posted on 11/03/2010 8:51 PM
OK....just finished roasting using the new profile. Panama Elida Natural Process and Kenya PB Kirinyaga. Both were roasted as follows:
Preheat 400 for 3
465 til C1
435 til end
2min drum cool/Pull for manual cool
Very interesting and I cant wait to see the results! A note of interest is that my roasts have always, for the most part, started C1 @ 17.4 on the GC timer (that's counting down from 30m for you lay folk:)). Both of tonights roasts hit C1 @ 20.0! I woulda thought that lower temps would mean slower roast.
Thanks for the idea, JD...and I'll post the results in a few days:)
 
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John Despres
Top  #9 Print Post
Posted on 11/04/2010 9:10 AM
Hey, Smatty,

Did the Kenya roast a bit darker than the Panama? I ask because the Kenya may be a bit softer. I assume the Panama is graded SHB and probably more dense.

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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smatty1
Top  #10 Print Post
Posted on 11/04/2010 5:48 PM

Quote

John Despres wrote:
Hey, Smatty,

Did the Kenya roast a bit darker than the Panama? I ask because the Kenya may be a bit softer. I assume the Panama is graded SHB and probably more dense.

John


Yeah, but I was shooting for a little darker on that one. I wanted to go darker than I did on the Panama, but it was still fairly light 4 min past C1 and I got scared and ended the roast not wanting to enter C2:)
 
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Third Crack
Top  #11 Print Post
Posted on 11/05/2010 6:52 AM
John, Smatty and whomever,
Speaking of getting scared and ending a roast......I used a profile similar to John's as I mentioned in my last post. Nice results with a hard bean (Kenya). It was still a bit too bright/acidic but I think that is because I wound up dumping at City at the end of first crack. Sweet Marias had recommended City+ to FC+ for this bean. The reason I dumped was color development. The color seems to me more like City+ to Full City so I got nervous and dumped. I have very little experience but I used to buy roasted coffee from George Howell (I believe one of the best at light touch roasting) and judging color it seems there is a disconnect between what I am getting and what I purchased (which are all in the City to Full City range. Do some beans just get darker at a given roast/temp stage? Should I ignore the color and go by time after first crack? Does profile have an effect on color for a common roast stage? It seems like color and temp go together so regardless of profile you should get a certain color at a certain point like City+. Anyway, if you have any guidance I would appeciate it. Bob
 
John Despres
Top  #12 Print Post
Posted on 11/05/2010 3:06 PM
Hi, Bob.

Others should chime in here, but color will not be the same for every bean. That said, we Gene Cafe owners have the advantage of a glass drum and the ability to see the beans, however, the beans will look darker through the glass.

Using color is not the best best way to judge a completed roast, but as you're just getting started, it's not a bad way to get you moving along, but don't rely on color entirely.

Using a Gene Cafe, I think time is the best way to judge. That and hours of experimenting to learn your roaster.

Keep extensive notes including everything you do. I have a log sheet I'm willing to send you. PM me your e-mail address and I'll fire it off to you. It will also give you an idea of what and how I track information.

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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smatty1
Top  #13 Print Post
Posted on 11/06/2010 10:30 AM

Quote

smatty1 wrote:
OK....just finished roasting using the new profile. Panama Elida Natural Process and Kenya PB Kirinyaga. Both were roasted as follows:
Preheat 400 for 3
465 til C1
435 til end
2min drum cool/Pull for manual cool
Very interesting and I cant wait to see the results! A note of interest is that my roasts have always, for the most part, started C1 @ 17.4 on the GC timer (that's counting down from 30m for you lay folk:)). Both of tonights roasts hit C1 @ 20.0! I woulda thought that lower temps would mean slower roast.
Thanks for the idea, JD...and I'll post the results in a few days:)


OK, here are the results:
Kenya PB:
I'm guessing John's questioning on this one was hinting that this may not have been the best profile for this bean. Initial piping hot sip was red zingery. Very pungent and bitter. As it cooled, the bitter got more intense. Complex, not totally unenjoyable, yet a bit offputting. A few more days in the jar may mellow this one out a bit, but not crazy about it today. So maybe a quicker ramp up for Kenyas? Note that I wasnt overly impressed with this bean with a faster/hotter ramp either.
Panama Elida NP:
This one turned out great! Fruity and creamy! A faster/hotter ramp did not bring out those flavors the last time I roasted this one. Now this is a fantastic cup of coffee!
So there ya have it. And the journey continues!:)
 
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John Despres
Top  #14 Print Post
Posted on 11/06/2010 5:43 PM
I'm thinking the Kenya won't improve much... Maybe a bit. Kenya coffees are mostly grown from 4,000 to 7,000 feet... For the lower grown, softer Kenya I would have started at a lower temp. Maybe preheating to 350F instead of 400F. George Howell says Kirinyaga is at 5000 feet.

Here's what Tom says about it in his notes:
"it is slightly winey, somewhat minerally in accent, and lingering and vivid bright-souring note on the tongue. Sour sounds unattractive, and this is very attrractive, but heck, it's sour! I used to call it "tongue-twisting East Africa flavor", something in the cup that seems to grab hold of the tongue and take it for a ride while the coffee sits on the palate. While it might sound unattractive and, well, rude, it's what can make a Kenya complex and unique too. The cup has citrus brightness with additional citrus rindy notes, grapefruit and true lemon, a bracing brightness. As the cup cools, the lighter roasts seem incredibly potent in their brightness. City+ to Full City offer more balance in the cup."

So, maybe you nailed and just don't like the coffee. Try a lower charge temp and see what happens.

I'm just starting to figure this new higher charge temp profiling myself. Anything you share will help me!

Do you keep track of what time and at what environmental temp your beans turn yellow? For me, without a bean temperature probe, that's a visual clue as to how fast your roast is progressing. Shoot for about 5 minutes.

Keep playing, have fun and keep us posted!

Thanks for your input on this; I'm still figuring it out.

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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Marshall_S
Top  #15 Print Post
Posted on 11/06/2010 9:42 PM
I've been playing with JD?s profile for about a week and have some interesting results I?d like to share.

I need to say, right off, that my cupping skills are very unsophisticated so bear with my simplistic descriptions.

Here?s what I did:

I first roasted 227 grams of some Bolivian Angel micro-lot and some Burundi Bourbon with my current profile. This profile is a slight variation of Eddie Dove?s early profile: Preheat to 350, a 5 minute dry out @300, a ramp all the way up to 482 and then 454 from C1 to the finish. I use a variac to keep my draw down to around 118V and I do an E stop cool in a shop vac/ colander.

With this profile, I got a nice Full City with both beans (no second crack) with a roast time around 16 minutes (first crack at around 12 ). The flavors were a bit muted but reasonably close to the descriptions of the supplier.

Now with John?s profile:

I followed his profile ?to a t? and I had yellowing at around 5 minutes, first crack at about 10 minutes, dropped to 444 and stopped the roast at 14 minutes.

The roasts were very different this time. On John?s, the flavor of the bean was less muted, more pronounced, and it had a milder, sweeter taste. Very nice and also very close to descriptions of the supplier.

I then decided to tweak his profile, seeing how far I could push the envelope for more flavor and a deeper taste without hitting second crack. I set my temperature up to 480 (rather than 465) and as soon as I got the first outlier of first crack, I lowered the temp and let it roast @470 for 30 seconds. I then finished the roast @451 (rather than 444) for another 4 minutes.

I hit first crack@10 minutes and achieved a wonderful, rich Full City @14 minutes with a weight of 192 grams. A bit more developed without any harshness!

For my taste, I?m having a slight preference for this profile. I?ll have to see how it fares with other beans over the next few weeks.

I?m convinced that getting to first crack as quickly as possible with the Gene is a good thing and that a 4 minute period of time between first and the beginning of second crack is ideal.

I also believe that John?s suggestion of getting the chamber smoking hot at the onset, and skipping the dryout, is key.
Edited by Marshall_S on 11/06/2010 9:42 PM
Marshall Schmidt
Foxboro, MA
 
smatty1
Top  #16 Print Post
Posted on 11/06/2010 11:14 PM

Quote

John Despres wrote:
I'm thinking the Kenya won't improve much... Maybe a bit. Kenya coffees are mostly grown from 4,000 to 7,000 feet... For the lower grown, softer Kenya I would have started at a lower temp. Maybe preheating to 350F instead of 400F. George Howell says Kirinyaga is at 5000 feet.

Here's what Tom says about it in his notes:
"it is slightly winey, somewhat minerally in accent, and lingering and vivid bright-souring note on the tongue. Sour sounds unattractive, and this is very attrractive, but heck, it's sour! I used to call it "tongue-twisting East Africa flavor", something in the cup that seems to grab hold of the tongue and take it for a ride while the coffee sits on the palate. While it might sound unattractive and, well, rude, it's what can make a Kenya complex and unique too. The cup has citrus brightness with additional citrus rindy notes, grapefruit and true lemon, a bracing brightness. As the cup cools, the lighter roasts seem incredibly potent in their brightness. City+ to Full City offer more balance in the cup."

So, maybe you nailed and just don't like the coffee. Try a lower charge temp and see what happens.

I'm just starting to figure this new higher charge temp profiling myself. Anything you share will help me!

Do you keep track of what time and at what environmental temp your beans turn yellow? For me, without a bean temperature probe, that's a visual clue as to how fast your roast is progressing. Shoot for about 5 minutes.

Keep playing, have fun and keep us posted!

Thanks for your input on this; I'm still figuring it out.

John

Haha! I think you're right about nailing the roast and just not liking the coffee. Perhaps I'm a bit of a simpleton, but 'sour' tastes more like vomit to me and less like a grapefruit raspberry cedarwood sorbet with a hint of baby tobacco leaves :)
My beans were yellow @ 4.5- 5 mins. I did not log info on time or temp @ color change.
Thanks for the input, John! I will be playing with this profile in the days ahead.....lot's of coffee roasting for the next 2 months:)
 
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Third Crack
Top  #17 Print Post
Posted on 11/07/2010 9:19 AM
My first attempt at duplicating John's profile: Preheat to 375; 120 V until 465; 95V at FC to maintain about 445. After a couple extra days of rest the coffee (Kenya bean) balanced out more and I was happy with the results. Yellow was in 4 minutes and FC at less than 9 minutes so I will refine as follows: Preheat to 375; 110V until yellow; 120V until 465; 95V until about 30-45 seconds past the end of FC. We will see if that minor correction produces any noticeable change.
Bob
 
RichC
Top  #18 Print Post
Posted on 11/07/2010 10:11 AM

Quote

rreusch wrote:
My first attempt at duplicating John's profile: Preheat to 375; 120 V until 465; 95V at FC to maintain about 445. After a couple extra days of rest the coffee (Kenya bean) balanced out more and I was happy with the results. Yellow was in 4 minutes and FC at less than 9 minutes so I will refine as follows: Preheat to 375; 110V until yellow; 120V until 465; 95V until about 30-45 seconds past the end of FC. We will see if that minor correction produces any noticeable change.
Bob


Is there any concern that running the Gene at 95 volts might be harmful to the electronics of the Gene? I seem to remember reading somewhere that it was best to run 120v appliances within +/- 5% of the voltage requirements on the UL tag of any appliance. That being said, if the Gene is a 120v appliance, the "safe" operating range would be 114v-126v. I have always tried to keep the Gene within those voltage parameters. I am interested in knowing if I am being too cautious.
Gene Cafe, Kyocera Hand Grinder, Baratza Vario, Aeropress
 
smatty1
Top  #19 Print Post
Posted on 11/08/2010 6:33 AM
Had another go yesterday with mods per JD's suggestions:
Bali Kintamani DP and Madagascar Robusta. Used this profile for both:
Preheat 350 for 3
455 til C1
435 til end
2 min drum cool
Pull for manual cool
Results to come....
 
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gene
Top  #20 Print Post
Posted on 11/08/2010 11:04 PM
Snowed under with work but just have to break my long silence and chime in here.
You have discovered what I found out a long time ago. John is the dean of Gene Cafe users and a real go-to unselfish guru.
Since I began using his profiles last year everyone says my roasts are "the best coffee they have ever, etc., etc".
My son gifted me ten pounds of Eth Jimma last month.
Looked over John's shoulder(AGAIN) and used preheat, then 350 for 3 min.
Cranked it up to 465 fot this and most roasts.
From there I log every minute of hundreds of roasts up til 10 min's.
Typically 6:00 is 399 7:00=406 8:00=419 9:00=428 10=433
Outlying crack 11:50 and 1st C 12:00 Time down to 440 at 12:20
Hit cool at 15:00 Voltage around 122. And I pay close attention to Tom to try to center the sweet spot.
I use the same profile for Kirinyaga. Temps above may vary but no more than 5 degrees.

As a point of interest spent last week in DC with son who works out there. Hit most coffe shops up there, Arlington, Alexandria. They sure have a strong Counter Culture presence. Did notice that most CC roasts are lighter than mine.
John is so correct on color, have to really concentrate on color in the future
Gotta run, sure enjoyed the posts on this topic.
gene
 
smatty1
Top  #21 Print Post
Posted on 11/10/2010 9:17 PM

Quote

smatty1 wrote:
Had another go yesterday with mods per JD's suggestions:
Bali Kintamani DP and Madagascar Robusta. Used this profile for both:
Preheat 350 for 3
455 til C1
435 til end
2 min drum cool
Pull for manual cool
Results to come....


Another roast night using the above profile:
PNG Amuliba A.... Results to follow....
Edited by smatty1 on 11/10/2010 9:30 PM
 
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smatty1
Top  #22 Print Post
Posted on 11/10/2010 9:40 PM

Quote

smatty1 wrote:
Had another go yesterday with mods per JD's suggestions:
Bali Kintamani DP and Madagascar Robusta. Used this profile for both:
Preheat 350 for 3
455 til C1
435 til end
2 min drum cool
Pull for manual cool
Results to come....


Fist taste of Bali this morning. Not overly impressed. This profile I had used before with this coffee was better I think. That was also a JD profile and was:
300 for 5
476 til C1
444 til end
2min drum cool-Manual cool
*That being said, this coffee is probably amazing with any profile and is still a dang fine cup of coffee!

Hard to judge the Robusta. First go on a new lot. I can say I was not disappointed:)
 
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smatty1
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Posted on 11/13/2010 2:08 PM

Quote

smatty1 wrote:

Quote

smatty1 wrote:
Had another go yesterday with mods per JD's suggestions:
Bali Kintamani DP and Madagascar Robusta. Used this profile for both:
Preheat 350 for 3
455 til C1
435 til end
2 min drum cool
Pull for manual cool
Results to come....


Another roast night using the above profile:
PNG Amuliba A.... Results to follow....


Day 3:
HUGE smokey flavor! A hint of a fruity snap as the smoke fades. Nice change of pace. I'd say that profile worked pretty well for that one...
 
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smatty1
Top  #24 Print Post
Posted on 11/13/2010 3:56 PM
3 roasts today:
El Salvador Finca Kilimanjaro, Colombia San Augustin, and Yemen Mokha Sharasi.
All with same profile:
Preheat 400 for 3
465 til C1
435 til end
2m drum cool-pull for manual cool
 
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smatty1
Top  #25 Print Post
Posted on 11/26/2010 8:43 PM
Still playing with this profile. Getting some interesting results. A couple of questions:
1. Why the elimination of the drying stage?
2. How did you arrive @ 350-400 for the charge temp?
 
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