Crash/Flick, Airflow and Roast Profiles with Toper Cafemino Electric - Page 2

Discuss roast levels and profiles for espresso, equipment for roasting coffee.
edpiep

Postby edpiep » Mar 15, 2019, 10:26 pm

Rush wrote:I tried literally 353 times to do so, couldn't do it. If you want to show me how I'd gladly pay any reasonable fee for that pleasure!


There is an R & L thread going on right now in this forum with a mega crashy Mexican Nayarita bean that you might glean some info off of too...

Rush

Postby Rush » replying to edpiep » Mar 16, 2019, 2:05 am

Thanks, I'll check it out.

Here's the thing about airflow, we know the airflow settings but not the actual airflow through the roaster. At full airflow from my roaster, it can just put out a lighter, at the 4" exhaust outlet. At 50% it stays lit easily. I'm guessing this doesn't qualify for high airflow generally speaking. Certainly multiples of CFM/bean mass lower than an air roaster, right? I wish there was a way to easily measure and communicate airflow through a roaster.

With regards to using heat to manage the crash and flick, I have experienced a huge crash and then giant flick, all with zero heat input at all. I will see if I can find one that bounced from 15, crashed down to 3-4, then flicked above 20 ror all with the elements all the way off for ~2 minutes before the flick.

I appreciate the feedback, just wanted to give more info that I should have included in the OP. I wish I could control the crash and flick with only heat, that would be ideal for sure.

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Almico

Postby Almico » Mar 16, 2019, 9:54 am

Rush wrote:I tried literally 353 times to do so, couldn't do it. If you want to show me how I'd gladly pay any reasonable fee for that pleasure!


With roasting, just like brewing coffee, it's important to learn to completely control the environment before expecting anything good to come from it. Only then can you start working on profiling coffee for maximum results. Sure, you might get lucky, but the odds of repeating luck are not good.

I'm still learning to control my roaster, but I'm getting there.

I was finding that although I was preventing a crash, the RoR was still sloping downward too quickly for darker roasts. The natural profile curve of my roaster was concave, losing too much heat momentum during the dry phase. To correct this I designed this profile the other day with a more convex curve in an attempt to be able to hit 2C and 415* before my RoR dropped too much.

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Using that curve as my background template, I needed to start with low heat and slowly add through dry in order to get my RoR curve to conform.

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But the RoR still dropped to low to reach a good 2C so I tried again. This coffee is a straight Brazil and RoR tends to increase at 1C instead of drop. The hump is during the +/-45s no touch zone, but I still managed the roast fairly well. Next time the 17% adjustment at TP needs to be 25% and that 12.5% adjustment before 1C needs to be 8.3%. This one did hit 2C and 417* in 12:22. You can see all my heat adjustments below. The air was never touched.

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To help reconcile the numbers, it should be noted that the first roast is 8# and the last one is 6.

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chuckcoffee

Postby chuckcoffee » Mar 16, 2019, 7:26 pm

Alan

That really is helpful to see this technique to make a slower roast and lessen the slope of the ROR basically pushing out when the ROR will hit the inflection point. I am posting a recent Guat roast just for comparison where my avg ROR slope is steeper. Typically for me once the ROR hits 10 its going to start going the other way. So I will try this to basically push out when it will hit 10. of course much smaller batch size at 1 lb

This roast was pretty good with a small fruit flavor.

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edpiep

Postby edpiep » Mar 16, 2019, 8:19 pm

I agree with Chuck, that's a good technique to master and helpful to observe. I will practice that as well to see if I get better results in the future.

I'm curious though Alan, was the first roast you show above better than the second "hump" roast in term of sweetness?

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Almico

Postby Almico » Mar 17, 2019, 1:35 pm

chuckcoffee wrote:Alan

That really is helpful to see this technique to make a slower roast and lessen the slope of the ROR basically pushing out when the ROR will hit the inflection point. I am posting a recent Guat roast just for comparison where my avg ROR slope is steeper. Typically for me once the ROR hits 10 its going to start going the other way. So I will try this to basically push out when it will hit 10. of course much smaller batch size at 1 lb

This roast was pretty good with a small fruit flavor.

<image>


I would avoid adding heat post dry end. I tried it on my air roaster 6 ways to Sunday and the results were never positive. I find with my roaster, the RoR curves slacks during dry when moisture is leaving the bean. I have to reduce maximum heat by DE or the curve will flatten. This makes sense since there is much less free water to keep the temp down.

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hankua

Postby hankua » Mar 19, 2019, 10:17 pm

Rush wrote:Thanks, I'll check it out.

Here's the thing about airflow, we know the airflow settings but not the actual airflow through the roaster. At full airflow from my roaster, it can just put out a lighter, at the 4" exhaust outlet. At 50% it stays lit easily. I'm guessing this doesn't qualify for high airflow generally speaking. Certainly multiples of CFM/bean mass lower than an air roaster, right? I wish there was a way to easily measure and communicate airflow through a roaster.

With regards to using heat to manage the crash and flick, I have experienced a huge crash and then giant flick, all with zero heat input at all. I will see if I can find one that bounced from 15, crashed down to 3-4, then flicked above 20 ror all with the elements all the way off for ~2 minutes before the flick.

I appreciate the feedback, just wanted to give more info that I should have included in the OP. I wish I could control the crash and flick with only heat, that would be ideal for sure.

There is a way to get a better handle on the airflow; install a used Dwyer Magnehelic tubed into the plenum. If you have the traditional style damper flapper I think you'll find this very useful. Electric drum roasters don't work the same as gas machines due to the response lag with heat changes. If you get the air pressure gauge installed, you'll be able to narrow down more settings that are repeatable for your machine. I've done the entire mod including drill/tap, gauge, fittings, tubing for less than $50.

Marcje

Postby Marcje » Mar 20, 2019, 4:55 am

Are the Artisan graphs here from elictrical Toper Cafeminos?
Reason why I'm asking is that I think I understand the generic priniciples to produce a roast (say witha a declining RoR), but I cannot replicate such a declining RoR curve myself. Mine stays very flat. And the coffee actually tastes ok.
I suspect that maybe because of the cafeminos design?

So I'd be interested to see the curves of actual cafeminos here :-)
@Rush: Maybe you have some?

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Almico

Postby Almico » replying to Marcje » Mar 20, 2019, 7:51 am

Post a picture of your Cafemino showing where the BT probe is located. Most Turkish roaster mfgs, including mine, have no clue where to locate a BT probe.

Marcje

Postby Marcje » Mar 20, 2019, 1:38 pm

BT:
(there are actually 2 thermocouples in the probe, one goes to the Cafemino, the other one is for Artisan)

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ET:

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