Does "Always Decelerate ROR and flicks" really matter? - Page 2

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

mkane wrote:For the rookie roaster I am Scott's guidelines give me a shot at a good tasting coffee. Before I found this site & one of Scott's books I didn't have a clue what a declining RoR was.
I've done 7 minutes roasts and 14 minute roasts. I've roasted fully-developed delicious coffee at 80 Agtron and sweet, non-roasty coffee at 45. I've done fast start slow finish roasts and slow start fast finish.

There is a whole lot you can do with a steadily declining RoR. The only thing you really can't do is turn up the gas mid roast. Like you mentioned in a previous post, you need to get it hot enough at the start without scorching and then gradually reduce the heat as the roast goes along. I have never experienced any coffee that I've roasted that improved when I added heat mid-roast. I will sometimes turn upon the gas just past turn around to get a roast on a better track, but not after 1/2 way to dry and beyond

Bunkmil
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#12: Post by Bunkmil »

Almico wrote:Not if the probes and software are the same, and that's an easy fix.
That looks like a bit simplistic.

Every roaster have different design (drum thickness, conduction/convection ratio, heat source, airflow design, batch size, etc.)

I don't believe that placing the same probe, using the same software and executing the same curve on totally different machines will lead to the same cup of coffee. At all.

I might be wrong but a roasting system is just too complex for that affirmation to be true.

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Almico
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#13: Post by Almico replying to Bunkmil »

Not saying executing the same curve on different machines. The quote was: "What looks constantly declining on my machine might involve a flat or increasing section on yours." We're only talking about measuring the bean temperature. Different probes in different positions will measure things differently. The same probes, in the same positions with the same interpretation device and the same software will show very similar curves. How you execute those curves on different roasters is a whole other thing.

OldmatefromOZ
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#14: Post by OldmatefromOZ »

Almico wrote:I've done 7 minutes roasts and 14 minute roasts. I've roasted fully-developed delicious coffee at 80 Agtron and sweet, non-roasty coffee at 45. I've done fast start slow finish roasts and slow start fast finish.

There is a whole lot you can do with a steadily declining RoR. The only thing you really can't do is turn up the gas mid roast. Like you mentioned in a previous post, you need to get it hot enough at the start without scorching and then gradually reduce the heat as the roast goes along. I have never experienced any coffee that I've roasted that improved when I added heat mid-roast. I will sometimes turn upon the gas just past turn around to get a roast on a better track, but not after 1/2 way to dry and beyond
Just my latest thoughts...

Im not a pro but do roast for others and have experimented with all sorts of different approaches over 10K small batch 400g drum roasts, including many 100s attempts of S curve where heat needs to be gradually added mid roast to direct the ramp through first crack and beyond...
I tend to agree with Alan, but I remain open to being shown otherwise.

I wonder does it just come down to different taste expectations / abilities / genetics?
Do some people perceive the flavour outcomes of the S curve as sweeter because of X and vice versa with Decline ROR?

I would love to cup the best examples of both styles blind where the same green coffee was used.

My experiments with small KL air roaster and drum roasts suggest there is something to the claim of 100 sec between start of yellow colour change to start of brown even with a decline ROR, for maximising sweetness. Colour changes are still fairly arbitrary as to what the individual sees unless one has had heap of practice / calibration in person with someone more experienced.

N3Roaster
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#15: Post by N3Roaster »

I think a lot also just has to do with where you put your preferred roast level. That decision of how dark to roast the coffee truly is responsible for the vast majority of differences in flavor and can easily influence what timing manipulations work best within the context of that coffee at that degree of roast. A while back I linked to this write up of a training exercise going from an ugly largely uncontrolled toward the end batch with 16 cups pulled across different roast levels and then picking three distinct roast levels to develop into proper production plans. The light roast does the declining rate thing, the medium roast is what was shown in a recent thread with the really stretched out yellow and an increasing rate going out of that, the dark roast was an S curve. Extremely different flavor profiles from the different roast levels with controlled profile differences to accentuate different aspects.

Most of the coffee from the final three test batches went out as gifts to other coffee people, with most sending feedback at varying levels of detail. At least a couple put the coffees on the cupping table for their sensory or QA panels at work and one sent back a very detailed sensory report with scores (that's one of the things his lab does for other companies). The medium roast ended up scoring highest there, but with only three points difference between the top and bottom scores I think it's fair to say that the points don't matter in the face of such vastly different overall flavor profiles. The more interesting thing here is that there wasn't any kind of consensus for what the preferred or least preferred roast was. I'm hoping to use the same coffee for a future class, doing a couple different profiles each at 3-5 different roast levels simply because this particular coffee has so many delicious possibilities available and it really drives home the message that your intent for the coffee matters and that intent should influence how you choose to roast a coffee.
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ymg (original poster)
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#16: Post by ymg (original poster) »

Thank you all for replying

I pretty match begginer to drum roasting , but from the experiments that i have made, the "Alway Decelerate ROR" gave me poor result, specially when going little dark as Neal mentioned.

I am focusing in the meanwhile on when do i want to spend my time and when to drop the beans, since there are no clear answer to this one, this will be in the"Alway Decelerate ROR" will be only secondary goal right now...if at all...

dale_cooper
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#17: Post by dale_cooper »

I would say 95% of people doing a RAO curve, are not executing a RAO curve. There is an absurd amount of misinformation and misunderstanding of terms like "baked", and RAO's actual guidance specifically. If you only know what you read in his book, you actually don't know anything. I'm not saying that to sound arrogant - its just that there is more to it than a downward descending curve.

In general, RAO's advice offers a repeatable, some what basic thing to shoot for (basic but takes serious time to figure out how to control your roaster to execute), that ends up producing VERY enjoyable coffee. If you're a pro roaster, why wouldn't you be going down that path? If I know that a particular roasting style produces very balanced, delicious coffee, why wouldn't I just keep doing that? I'm not saying RAO's way is the only way... if you don't like it, just do your own thing and create your own regimen, but make sure its something you can repeat.

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GC7
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#18: Post by GC7 »

N3Roaster wrote:I think a lot also just has to do with where you put your preferred roast level. That decision of how dark to roast the coffee truly is responsible for the vast majority of differences in flavor and can easily influence what timing manipulations work best within the context of that coffee at that degree of roast. A while back I linked to this write up of a training exercise going from an ugly largely uncontrolled toward the end batch with 16 cups pulled across different roast levels and then picking three distinct roast levels to develop into proper production plans. The light roast does the declining rate thing, the medium roast is what was shown in a recent thread with the really stretched out yellow and an increasing rate going out of that, the dark roast was an S curve. Extremely different flavor profiles from the different roast levels with controlled profile differences to accentuate different aspects.

Most of the coffee from the final three test batches went out as gifts to other coffee people, with most sending feedback at varying levels of detail. At least a couple put the coffees on the cupping table for their sensory or QA panels at work and one sent back a very detailed sensory report with scores (that's one of the things his lab does for other companies). The medium roast ended up scoring highest there, but with only three points difference between the top and bottom scores I think it's fair to say that the points don't matter in the face of such vastly different overall flavor profiles. The more interesting thing here is that there wasn't any kind of consensus for what the preferred or least preferred roast was. I'm hoping to use the same coffee for a future class, doing a couple different profiles each at 3-5 different roast levels simply because this particular coffee has so many delicious possibilities available and it really drives home the message that your intent for the coffee matters and that intent should influence how you choose to roast a coffee.
Thank you for this post. I found it really insightful and explains a lot.

ymg (original poster)
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#19: Post by ymg (original poster) replying to GC7 »

Yes me too.

Thanks Neal and all ....

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Almico
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#20: Post by Almico »

dale_cooper wrote:I would say 95% of people doing a RAO curve, are not executing a RAO curve.
I would agree. That's why I added that qualifier to my statement, The only people that have differing opinions on this are people that haven't tried it enough to get it right, or been able to achieve it the right way. It is not easy and especially difficult on darker roasts where you need to carry enough heat into 2C and not flick.

I guess the other qualifier would be, "Unless you like really dark, roasty coffee". Then I suppose it doesn't matter.

I did two roasts last night of two different Brazils. The Mogiana likes going dark. It is nutty and chocolatey roasted to 415* on my roaster. I get 2C at 418*, so this is drops with a few 2C outliers. 420* is my limit on any coffee. I've tried roasting into the beginning of a rolling 2C, to maybe 423* and I just don't like it. The coffee gets oily and looses freshness quickly as the oils go rancid in a few days.

This coffee is Agtron 50, about as dark as I like to go.



A new coffee I just found, Brazil Sitio Colinas, is the first Brazil I've roasted that loves the light zone. At Agtron 78 it almost tastes like a high grown Central. It has a most pleasing acidity that lingers on the tongue for days and gets better and better as the cup cools. There is a nice, sweet cocoa base for sure, but the kicker is a heady cardamom note that comes through before the beans are even ground. The cardamom is gone at Agtron 70 and most of the acidity by 60.



Both coffees are sweet as can be and neither spends 100 seconds in yellow. Quite the opposite. I open the air at DE which kicks the convective heat into overdrive. I'm trying to see if I can increase the sweetness even more by extending yellow, but not so far. I find getting as much energy into a coffee without burning it as soon as possible gets all the reactions going in the right direction. I believe it builds added pressure in the bean before water vapor has a chance to escape, acting like a pressure cooker and forcing heat to the inner bean, thus speeding development. This might be why Nordic roasters can get fully developed coffee at Agtron 90. When I slow this process, my coffee loses something.

It might have to do with the ratio of time spent in yellow and overall roast time. But I just can't bring myself to roast coffee for 15 minutes again. Coffee roasts by temperature far more than time. Sure, time is important. But you can roast coffee for 30 minutes and have it be raw if the temp never gets above 250*F. But you can't roast a coffee to 445* in 3 minutes and get the same result. Heat is what roasts coffee much more than time. And from my experience, coffee suffers from too much time spent in a roaster.
dale_cooper wrote:In general, RAO's advice offers a repeatable, some what basic thing to shoot for (basic but takes serious time to figure out how to control your roaster to execute), that ends up producing VERY enjoyable coffee. If you're a pro roaster, why wouldn't you be going down that path? If I know that a particular roasting style produces very balanced, delicious coffee, why wouldn't I just keep doing that? I'm not saying RAO's way is the only way... if you don't like it, just do your own thing and create your own regimen, but make sure its something you can repeat.
Agree again. What Scott's RoR profile does is eliminate roast defects while maximizing dynamics of flavor, at whatever BT roast profile you want, except ones where you need to turn up the heat mid-roast. In my mind, I am very content with that. It simply lets the flavors inherent in the coffee come through instead of employing roasting gymnastics to try and evoke some elusive flavor note. Repeating that effort is difficult at best. At worst, the coffee is giving up sweetness and possibly adding baked and/or roasty flavors in exchange for the effort.