How to Profile Article: brain storming session

Discuss roast levels and profiles for espresso, equipment for roasting coffee.
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#1: Post by another_jim »

For the umpteenth time, someone has asked for profiling advice; and for the umpteenth time, the more experienced home roasters have given the conventional wisdom: that there are some profiling generalities, but that exact profiles are roaster and coffee specific.

Can we do better? Can we put together a good set of profiling information?

This is a brainstorming session, so all ideas from people at all experience levels are welcome.
Jim Schulman

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#2: Post by another_jim (original poster) »

I'll kick the session off; and you can all tell me how full of it I am.

Seems to me that each roaster (machine) needs a basic profile, the one to use on a new coffee, and the one to tweak to get the right roast for a known coffee. So maybe the article should focus on how to find that basic profile, and how to tweak it. We can do this in general, "this is how you do it for all roasters" and people can share their results for specific roasters, particularly the off the shelf ones.

For instance:

My general advice is that the profile has
-- a drying phase to 300F bean temperature (BT),
-- a first ramp to the first crack at around 390 BT,
-- and a finishing ramp to the end of the roast.

A basic profile would tell people how long each of these phases should be for their roaster. I would advise people to set up their basic profile so it produces a really good light roast, pulled just after the first crack ends. The acid test is to get some green and roasted (for brewing) beans from Terroir (the best light roasters in the country) and see how your equally light roast stacks up.
-- It should have no grassy flavors (too short a drying phase), or dusty, leathery, or choking ones (too long a drying phase),
-- it should not taste bready or like cheerios (too long a first ramp), or have no toasty flavors at all (too short a first ramp),
-- it should not taste overly acidic (too short a finishing ramp), nor should it taste flat and caramelly (too long a finishing ramp)

I would advise people to keep the length of all three roast phases mostly the same for any degree of roast (light or dark), but to add a minute or two to the finishing ramp when going from brewing to espresso roasts, since you want the flavor balance to have more caramel and less acids.

Here's how to get some very basic profiling on a completely unmodified popcorn popper:

Drying phase: Run the roaster one minute, then turn it off for two minutes, then restart the roast. Increase or decrease the turnoff time to change your drying time.
First ramp: There is not much that can be done here
Finishing ramp: Use a lower weight of beans to lengthen the time, a higher weight to shorten the time.
Jim Schulman

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#3: Post by GVDub »

I dunno, Jim. I live in L.A. fairly close to sea level (under 500' above) with desert-like humidity levels (frequently single digit during dry periods and it rarely gets about 60% except for the infrequent occasions when it's raining). How helpful is a profile that I've developed (to the extent that you can vary profiles on the Behmor) going to be for somebody who lives at altitude or in a humid place? Unless we're both storing our greens in a climate controlled environment (which is never likely to be a luxury I can afford), we're going to have very different starting points, so running the same profile would likely end up with very different results, even if we're both using the same roaster.

Lots of folks around here have been roasting longer than I have, but after 6 years at it and well in excess of 1000 roasts, I'm not so sure that there's a 'magic formula' of precise steps to follow that will work for everyone.

edit: Although I'm more than willing to be convinced otherwise.
"Experience is a comb nature gives us after we are bald."
Chinese Proverb

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#4: Post by »

another_jim wrote:For the umpteenth time, someone has asked for profiling advice
Who's that newbie :mrgreen: ? Assuming he can join this session, here are his 0.02 USD worth of thoughts:

GO JIM! Seriously, though, all I can think of for this to work is an article per, available & profile-able, home roaster. On that roaster, 3-5 different "classes" of beans are profiled. With such an article written as a thread, we, the masses, reply with our own beans/results to reconfirm/clarify to other readers.

This is a brainstorming(i.e. dreaming) session, right?

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#5: Post by »

George, no magic formula indeed. But espresso extraction suffers from a similar problem; but we have 9bar, 25secs, brew temp, etc as guidelines that made decent home espresso possible. Cuz of the involvement of roasting, go one more level specific, and BINGO! now you have the equivalent of headspace, dose, steaming style, etc recommendation. The good thing with roasting is that there are very few different accessible roasters when compared to the number of espresso machines.

It's all about starting somewhere reasonable while having access to good advice...

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#6: Post by timo888 »

another_jim wrote: ... Terroir (the best light roasters in the country) ...
Agree with this praise of Terroir, but would say that PTs and Barefoot are also among the top light roasters. Barefoot, I think, has been actually the lightest of the three, then PTs, then Terroir.

Novo could cram into the phone booth too.

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#7: Post by Sherman »

I've been pondering this exact question for a couple of months now, and have come to the following conclusions:

*crickets chirping*

The best that I can offer so far is to learn how to accurately measure temperatures for your roasting method. The foundation for profiling is accurate and CONSISTENT temperature measurements. I believe that this holds more weight than sight or smell, as it is more objective and easily measurable.

Off the top of my head, I believe that JimG has hit the nail on the head for dogbowl/heatgun (DB/HG) measurements. IMAWriter might want to chime in for the Stir Crazy/Turbo Oven crowd, and
another_jim and others who are old pros at Poppery roasting can provide information regarding probe placement for the air roasters.

Know your roaster and which temperature measurement is applicable. From what I've read, there are 3 basic measurements that have been shown to be of significance - environment temperature, bean mass temperature, and exhaust temperature. The basis for profiling as it relates to your roaster is to know which of these three can be: A) most accurately measured, B) most easily repeatable, and C) whose change has a significant effect on the final product.

More rambling to come,
Your dog wants espresso.
LMWDP #288

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#8: Post by iginfect »

Don't understate the importance of the envirornmental temp. Below freezing, i.e. all winter long I have to move from the garage into the house under the hood which is over the stove. and adjust for temps in 30's degF.


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#9: Post by another_jim (original poster) »

It refers to the temperature inside the roaster, the beans' environment, not the roaster's.
Jim Schulman

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#10: Post by yakster »

Very interesting thread. I think that Marvin was stating that ambient temp (outside roaster) is important as well. Possibly humidity too. I noticed earlier this year that every time I went to roast it seemed to be raining. When I was roasting in poppers, I was huddled under the garage door trying to keep dry and keep the smoke under control. Now that I have a Behmor, I'm roasting on my bench and more comfortable. I never did correlate any effect of rain or humidity on my roasts, though.

I moved from poppers to a Behmor this year and have a thermocouple taped to the ceiling of the roaster (to the right of the light, angled down slightly and slightly behind the drum) and I've been logging my roasts with BehmorThing to try and temperature surf the Behmor beyond the built-in profiles. This is an ET probe, I have no BT probe.

I think that the conventional wisdom with the Behmor is that for most beans you start with a known load size and then run a P1 roast and note the time to first crack so that you can run the next roast on P2 or another profile with a temperature cut at or prior to first crack to slow down the bean momentum and extend the break between first and second crack. In addition, you can do things like open the door for 5 seconds every 15 seconds between first and second crack to try and get more time in this phase and open the door after a couple of minutes of cool cycle to cool the beans a little faster. (my shop-vac has a carpet attachment the width of the door that I use once the ET has dropped below 350 F or so to accomplish this while keeping the chaff in the roaster or vacuum)

My ET probe has shown me that there's more going on in the Behmor's programming then the charts indicate. There is a significant (40 degrees Fahrenheit or more) temperature drop programmed into the heating elements right before the afterburner is programmed to kick in, and this temperature drop occurs at different times based on the 1/4#, 1/2# or 1# weight settings on the roaster. This temperature drop occurs whether or not your afterburner is working.

The temperature drop occurs at about 3:30 (three minutes and thirty seconds) for the 1/4# setting, 5:00 for the 1/2# setting, and 7:30 for the 1# setting. You can see and hear this back-off on the heating elements, and should be able to see a change in the current/power draw on your electrical circuit as well (I monitor voltage but don't have a kill-a-watt to monitor current draw).

I have been trying to use these timings and bean load size to allow a nice ramp for the drying phase with the dip in temperature occurring at an opportune time before first crack to cut back on the bean's momentum allowing me to stretch out the time between first and second crack. I do a two minute pre-roast (run the Behmor for up to two minutes at P1 or P3 and hit stop then quickly enter the desired profile) to push the temperature drop closer to first crack, but you risk more smoke this way by delaying the afterburner kick-in (note, at some point the internal temperature of the Behmor will exceed a threshold that won't allow you to stop and then immediately re-start the Behmor, usually this is longer then two minutes, but for some cases it can be less then two minutes).

I've uploaded some roast charts showing these timings. These roasts have a two-minute pre-roast, but the temp drop will occur at the same time relative to the last time you hit start no matter if you pre-roast or not. The roast charts show different time scales which makes a side-by-side comparison more difficult, but they illustrate the point, I think.

1. A quarter pound roast of 4 oz of 2008 Brazil COE #1 "Faz Kaquend" on a 1/4# P1 A profile with a two minute pre-roast here.

2. A half pound roast of 7.4 oz of Sweet Maria's Mika Kadir Blend on a 1/2# P1 A profile with a two minute pre-roast here.

3. A full pound roast of 16 oz of Ethiopian Sidamo Organic Natural Process Korate on a 1# P1 B profile with a two minute pre-roast here.

All these roasts were logged with BehmorThing (manually) and I never left my seat in front of the Behmor or took my attention away from my roasts (no matter how much my Wife would try and distract me). If you pre-roast or use a 1# setting for a small load size, it's important to make sure that your prepared to attend the roast and be present for any emergent situations (chaff fires, etc.).

The attached graphs may not be my best examples of timing the temp drop to maximize the time between first and second crack, I posted them only to illustrate when the temperature drop occurs to make my point clear.

I'm thinking that this information could be helpful for others trying to maximize the time between first and second crack on a Behmor.


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