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allenb
OfflineAdmin
· 04/02/2020 4:50 AM
Morning Ed, I haven't done any green coffee hoarding yet but am hoping the supplies don't end up like the toilet paper isles!

snwcmpr
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· 03/31/2020 2:53 PM
Hey Ed. Thanks. roar

homeroaster
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· 03/31/2020 11:21 AM
Hey quarantined home roasters! I hope you have great coffee! If they have a run on coffee, I hope you're set with your great home roast! Find me on Facebook! Ed Needham

snwcmpr
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· 03/25/2020 11:49 AM
New Rochelle in the news. I think of you every time I hear it. ... Please stay safe.

allenb
OfflineAdmin
· 03/21/2020 7:36 AM
Good morning homeroasters morning Everyone is hopefully staying healthy through this. Hang in there and stay safe!

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Preheating drum
simagic
I've seen on many threads people speaking of preheating the drum. Some do and some did and don't do anymore. Some preheat 5 min at 300. some 4 min. some more.
Personally, I preheat to 375 because by time I remove my drum, load up and reset the dials, the temp has dropped down to approx the desired 300. BUT, here is my issue/question. I don't think it matters if you preheat at 300 for 5min, 10 min, 30 min or 15 seconds. If temp has reached 300, then it's 300.........( period). If it's preheating at 300 for 5 min. or 5 hours......IT"S STILL JUST 300 when you remove the drum. So when I see different threads speaking of different times at 300.....I SAY TO MYSELF , Just preheat (( til )) 300 plus a few seconds. But as i said in the beginning, I preheat (( til )) 375 to allow for the drop when removing drum. THEN, I warm and dry the beans (AT) 300 for a full 5 minutes. Dennis
 
John Despres
I tend to just preheat to 350F and stop. However, preheating for a longer period of time also heats the entire machine: the cover, the housing and whatever else may suck some heat from the warming drum.

Does it make a difference? Don't know, but you're correct, 300F is 300F inside the drum.

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.
 
www.sceneitallproductions.com
ciel-007

Quote

simagic wrote:
... I don't think it matters if you preheat at 300 for 5min, 10 min, 30 min or 15 seconds. If temp has reached 300, then it's 300.........( period)...


I agree Dennis. It is not a matter of how long your preheat the drum… as long as you DO preheat the drum. I hadn’t realized how important it is to preheat the roasting chamber until Ken raised the issue in another thread entitled “ When do you drop beans in?”
http://homeroasters.org/php/forum/vie...ad_id=2355

Since I began dropping the beans in at 350F, and seeking a rapid ascent to 1C, I have discovered a remarkable improvement in the flavor of my roasts. Ciel
Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
 
simagic
Hi Ceil. So I just read your reply and you say you're dropping in your beans at 350. Would I be correct in ass-u-ming, that you set it higher to 400 or so and by time you removed the drum, put in beans, reset time and temp and ready to get going again it has dropped to 350. ORRRRRRR do you mean you "SET IT at at 350 and then of course it will drop to under 300 by time you do "all that stuff". And then I need to ask.......If you're preheating your drum to 350, then is that the temp you are warming/drying the beans . Do you warm/dry at 350 as well? or do you warm/dry at 300. The reason why I ask this is because ( and if I'd have to find it again on this forum, it might take forever), is because I read "somewhere here, where someone said do not warm/dry at 350 because at 350 as opposed to 300, you are starting to bake the beans. ( I read this here somewhere)? dennis
 
John Despres
I posted something to that effect recently, Dennis.

It's not so much about baking the beans as it is about advancing too quickly.

Nothing good happens at 350F for 5 minutes. Too much moisture will be removed from the beans leaving little to carry the beans through first crack and into second crack. Over-drying the beans will leave a bitter roast with no acidity at all.

Over-drying too soon will start to heat the sugars way too early, thus the extreme bitterness.

A certain amount of bitterness is desired to counter the acidity, of course, but too much may be nasty unless one likes very bitter coffee.

JD
Respect the bean.
John Despres
Fresh Roast 8, Gene Cafe, JYTT 1k, Quest M3, Mazzer Mini, Technivorm, various size presses and many more brewers.
 
www.sceneitallproductions.com
simagic

Quote

John Despres wrote:

I posted something to that effect recently, Dennis.

It's not so much about baking the beans as it is about advancing too quickly.

Nothing good happens at 350F for 5 minutes. Too much moisture will be removed from the beans leaving little to carry the beans through first crack and into second crack. Over-drying the beans will leave a bitter roast with no acidity at all.

Over-drying too soon will start to heat the sugars way too early, thus the extreme bitterness.

A certain amount of bitterness is desired to counter the acidity, of course, but too much may be nasty unless one likes very bitter coffee.

JD
So are you saying that (( 350 )) for 5 minutes is not good or are you even saying that (( 300 )) for 5 minutes is not good as well??????? Are you saying just go from preheating the drum, straight into the roast. (( or )) warm/dry beans, but only to a max of 300 and not as high as 350. Not quite clear to me
Edited by simagic on 08/05/2012 2:14 PM
 
John Despres
Warm/dry your beans for 5 minutes at 300F.
Respect the bean.
John Despres
Fresh Roast 8, Gene Cafe, JYTT 1k, Quest M3, Mazzer Mini, Technivorm, various size presses and many more brewers.
 
www.sceneitallproductions.com
simagic

Quote

John Despres wrote:

Warm/dry your beans for 5 minutes at 300F.

Got it....
 
ciel-007

Quote

John Despres wrote:
... Too much moisture will be removed from the beans leaving little to carry the beans through first crack and into second crack. Over-drying the beans will leave a bitter roast...


John, can you expand a bit on the potential link between early drying and bitterness? What you may be suggesting seems counter intuitive - given that moisture begins to evaporate at a relatively low temperature (212F); I suspect that little moisture is left inside the beans by the time 1C (384F) arrives.

I have not yet seen studies associating bitterness with a rapid heat rise in the earlier stages of the roast. However, I have seen studies linking bitterness with prolonged roasting passed 2C; this is the point at which complex bitter compounds like chlorogenic acid lactones, and phenylindanes are apparently created. Ciel
Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
 
Barrie
Simagic, your questioning seems to imply that there is one set of circumstances that applies to all Gene Cafe roasters and I would respectfully suggest that this is not the case. For example
1. Line voltage differers from one house-wiring setup to another, with a resulting difference in rates of heating. To take it to the ridiculous, if you expose beans immediately to, say, 400F for a minute you get one set of chemical and physical changes. If you take half an hour to get there, then take the beans out, this will produce a totally different outcome. Also, different Gene Cafe machines in the same line voltage and ambient temperature circumstances may have their own performance characteristics.
2. Then there is always the difference between the response of a given bean or blend of beans to each roasting profile, as well as the effect of mass of beans on the temperatures.
3. Not finally, but last in my little list at the moment, is the issue that I think John mentioned. The performance of the roaster when the temperatures is at, say, 350, in a first roast is different when it is at the same temperature reading in a second roast soon after. On that occasion the whole hot air pathway has been heated up and everything happens more quickly.
I can only repeat the advice of many much more experienced roasters than me. Run some trials with your particular machine. Decide what gives you a taste that you like and stick with it. Of course, with a different bean you will not be going back to square one, but on the other hand you cannot apply the same routine for all beans. I hope this helps.
Barrie (San Diego, CA)
"So much to learn, so little time."
Hottop 2K+., Artisan, Jura Capresso ENA 3 (i.e. espresso).
 
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