Fluid Roasting - Flow Chart Suggestions

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

#1: Post by swiftcoffee »

I appreciate any thoughts or suggestions on this.
I am a big Ethiopian coffee fan. I personally enjoy the natural process beans flavors. Is there any advice or suggestions on what I should do to bring out the sweet and natural flavors out of the bean? In other words, are there any do's or don'ts in order to make this happen? Is there a certain temperature I should not go over? Any basic information on this would be greatly appreciated!

Thank you!

GDM528

#2: Post by GDM528 » replying to swiftcoffee »

I've read that natural-process beans have an extra outer coating of carbohydrates compared to washed beans, and that coating is more prone to scorching and burning. So, I lean toward thermal profiles that spend the least amount of time above 200C bean temperature. I also avoid thermal profiles that spike the temperature early in the roast to speed drying. I'm posting recipes that follow the aforementioned guidelines here: IKAWA Home - profiles They're for the Ikawa roaster, aka fluid-bed.

Are there some specific bean sources you can recommend?

swiftcoffee (original poster)

#3: Post by swiftcoffee (original poster) »

Thank you for the helpful reply!
I hope I am understanding your last question.

Below is the type of bean I am working with.
Crown Jewel - Ethiopia Organic Halo Bariti Addisu Kidane Raised Bed Natural

Thank you!
Mark

GDM528

#4: Post by GDM528 »

swiftcoffee wrote:Below is the type of bean I am working with.
Crown Jewel - Ethiopia Organic Halo Bariti Addisu Kidane Raised Bed Natural
Thanks for the tip on the bean supplier. 22lb order size = 1 year supply for my rate of consumption - LOL. They look like a good resource for roasting profiles. I don't own the Ikawa Pro, but despite that I was able to download Royal's profiles and view the time/temperature points off a table in the Ikawa Pro app (in 'Guest' mode).

I see their recommended profiles are linear-ramp, which creates a flat RoR curve, but I've been under the impression that a linear, steadily declining RoR was the roasting grail... Maybe the rules are different for fluid-bed.

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Peppersass
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#5: Post by Peppersass »

Last summer I roasted some Halo Bariti Natural I got from Happy Mug. I was still getting to know my Ikawa Pro V3. I tried three different profiles. The first two didn't go so well, but the third was pretty good. It was the Ikawa Pro Espresso 1 profile, cut back from 10:09 to 9:30, which slightly altered the slope of the curve after 1C. Here's how the roast went:



1C started at 7:57 at 410F. Drop was at 9:29 ar 424F (time after 1C was 1:32.) The roast measured 21 -- medium light (almost medium) -- on the Roast Vision scale, which is 82 on the Agrtron Gourmet scale. My tasing notes are "Bright, no fruit, sweet. Slight astringency. Nice."

The profile I now use is the same one cut back to 9:10:



I never let the roasts go that long. I drop manually 30-90 seconds after hearing the very first pop of 1C. Depending on the coffee, the shorter end of that range usually produces a light roast, while the longer end of that range usually produces a medium or medium light roast. Most of the coffees I've been roasting lately have dropped in the 45-60 second range for a light or medium light roast (more towards light than medium.) That's where I get the most fruit flavors and sweetness.

Note that my batch size is only 50g, so very likely times and temperatures would have to be adjusted for a larger fluid bed roaster like yours.

Also note that the time to 300F, which is where I mark dry (Color Change), has been almost exactly 2:24 for every coffee I've roasted with profiles based on Ikawa's Espresso Roast 1. (I was late marking 300F in the roast log shown above.) I've heard that timing in fluid bed roasters is faster than drum roasters, which this seems to confirm. I'm sure the dry time is also affected by the very small batch size. Development time and total roast time are somewhat shorter than what I used to see with my Quest M3, though not as dramatically shorter as the dry time.

My RoR curves are usually pretty flat. I think Ikawa could do a better job scaling that curve on the graph, though it would still not be gradually declining. I suspect Rao's declining RoR curve doesn't apply to fluid bed roasters, especially small ones like mine. All I can say is that I've gotten some outstanding results with the Ikawa Pro V3 using the above profile and technique, regardless of the RoR curve.

GDM528

#6: Post by GDM528 »

Peppersass wrote:Note that my batch size is only 50g, so very likely times and temperatures would have to be adjusted for a larger fluid bed roaster like yours.

My RoR curves are usually pretty flat. I think Ikawa could do a better job scaling that curve on the graph, though it would still not be gradually declining. I suspect Rao's declining RoR curve doesn't apply to fluid bed roasters, especially small ones like mine. All I can say is that I've gotten some outstanding results with the Ikawa Pro V3 using the above profile and technique, regardless of the RoR curve.
Speaking of times and temperatures, would it be possible for you to post a screenshot of the time/temp tables in edit mode?

You bring a message of hope and inspiration, to free the 'Ikawandians' from the shackles of drum roasting RoR-craft.

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Peppersass
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#7: Post by Peppersass »

GDM528 wrote:Speaking of times and temperatures, would it be possible for you to post a screenshot of the time/temp tables in edit mode?
Here you go:



My iPad screen isn't long enough to show the last part of the table, which has the cooldown time and fan speed.

Here's a screen shot of the data available from the roast log. I've scrolled down past the pre-heat data so you can see the information stored during the roast. As you can see it's quite extensive and may provide a basis for programming the inlet temperature on the Home 100g:


GDM528

#8: Post by GDM528 » replying to Peppersass »

Thank you sir! You've made me insanely jealous of your vastly superior app-age.

Ikawa is asking for $34 a month for access to what appears to be the previous version of their app that still allowed editing the setpoints. That seems really usurious to me - but if they offered the Pro app instead...

I see in your screenshot they're making what at least to me seem like really small changes to fan speed: from 69% to 67%... yikes.

I've heard the Pro's are peppered with extra sensors, but I can only identify one more than the Home. This is my attempt to decode the columns in your spreadsheet (any corrections appreciated):

"temp board" = Temperature of the circuit inside the Ikawa that's measuring the output voltage of the thermocouples. Necessary for accuracy.

"temp below" = Temperature just below the bean chamber. Perhaps that's what's called "inlet temperature"?

"temp above" = Temperature of the rather prominent stainless-steel probe in the upper portion of the bean chamber.

No exhaust temperature listed, so I'm guessing there aren't any more thermal probes after the bean chamber.