Rao on the Development Time Ratio - Page 2

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

#11: Post by Randy G. »

Boldjava wrote:Kindred spirits. Mine is, "When I come to the shop, if I don't learn something about coffee in any given day, my boss should fire me."
Love the videos, btw. Sent Joe an E-Mail. But your quote (and mine) point towards the art of roasting. If it could be done with pure science anyone could do it, and the product would be called Folgers or some such. :wink:

Just a few months ago I learned I'll never buy another naturally processed (fremented?) bean again. Maybe it's just me, but it smelled the same in the green as it did after roasting, and in the cup after brewing, and tasted like it as well. As Bogart said, "If me and the boys wanted a cup of well digger's arm pit sweat, we'd have ordered a cup of well driller's arm pit sweat."

And just to stay a bit on topic, I know your videos speak of keeping data cards/graphs, but being a visual learner has made Artisan software and real time graphing very valuable for me. Also having a computer controlled roaster that can operate the roaster on a temperature-priority basis. When a small, home coffee roasting appliance is a challenge, it is even more so when it is electric. But you have to dance with the "one ya brung," no? Combined with Scott's book it all combined to take me to the next step. You video on the TP and bean density is next!

As we stated at the start, there is always something more to learn when it comes to roasting, and just when you think you have a handle on it, a new crop comes in, or you get a new roaster, or the heating element or burner is changed, or someone changes a filter of cleans a fan's blades, or the electrical supply voltage changes, or the profile you used when it was 55 degrees was accidentally loaded when it was 90, etc., and you hear the profanity issuing forth from the roasting room.
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Boldjava (original poster)
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#12: Post by Boldjava (original poster) »

Randy G. wrote:... and you hear the profanity issuing forth from the roasting room.
...and we continue as kindred spirits.
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LMWDP #339

Unrooted

#13: Post by Unrooted »

The Cat And Cloud podcast recently discussed the Rao 20-25% and said it would result in too dark of coffee...but it's hard to figure out how they roast, but I can verify that they know what they are doing.

They do say that they hit a 17% development time though.

compellingrich

#14: Post by compellingrich » replying to Unrooted »

Rao mentioned this as well, but the 20-25% ratio is dependent on how full you're packing your drum's capacity during a given roast. I think this makes all the difference in planning a recipe around this style of roasting. In my experience a less-full drum batch is going to taste better, more-vibrant, towards 20%, whereas a more-full drum batch would need to be closer to the 25% range.

thepilgrimsdream

#15: Post by thepilgrimsdream »

I asked Scott on his blog about the WCRC profiles on his blog. Here was his response:

Hi Dan
While I'm not privy to all the relevant info I'd need from the competition (machine, probe, location, etc), I know that most successful competitors (wisely) use rather small batches, often 50% or less of the machine's stated capacity. If you read the section of my post "The Exception To The Rule", you'll see that a high gas power: batch size ratio allows you to finish roasts faster with less concern about development.


Makes sense to me.

I find 12-19% is usually pretty nice on my Quest. On large commercial roasters I'm hitting 19-23% development at 75-100% capacity.

max

#16: Post by max »

thepilgrimsdream wrote:I find 12-19% is usually pretty nice on my Quest.
Does this opinion change with roast size as well on the Quest?

thepilgrimsdream

#17: Post by thepilgrimsdream » replying to max »

I personally haven't experimented with batch sizes smaller than 150g, but it may just be my next experiment

treq10

#18: Post by treq10 »

When I read that post, a couple of points came to mind:

1. Rao's definition of development is subjective to his experiences. So YMMV is something that should be considered when incorporating his ideas. I am specifically talking about his palate here. Some like more origin notes, others more roast. I don't know what Rao's palate is like, but I think it's one of the deciding factors that contribute to him favoring a 20-25% DTR.
2. There can be more than one way to get even development without baking or underdevelopment. Rao's method might be one way that works consistently, but that doesn't mean that there aren't other ways to get to the target.
3. There's a factor that is more important than DTR - namely, the consistently decreasing RoR. You don't want stalling (results in baking), crashing, (underdevelopment) or both (baking AND underdevelopment). The RoR graph is a proxy to development quality as opposed to a precise indicator. It just happens that for Rao, a DTR of 20-25% is correlative to steadily declining RoR. It doesn't mean that you can't achieve even roasting with a different DTR.
4. Consider roasts of the same bean batch that takes 5 minutes, 10 minutes, or 15 minutes for a given roaster. The 20-25% DTR would be an afterthought to the overall roasting strategy for a given type of bean. But, it IS a good starting point to aim for. The roaster can shoot for 20-25% DTR as a baseline and tweak off of it perhaps. But ideally, each roaster will know after trial and error the baseline DTR that works for his/her specific setting.
5. The end goal is not to hit these subjective metrics. Rather, the aim is to roast coffee that is as delicious as possible to the person tasting it. Which means that these are guidelines rather than law.

Just things that came to mind while reading...

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Boldjava (original poster)
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#19: Post by Boldjava (original poster) »

thepilgrimsdream wrote:I asked Scott on his blog about the WCRC profiles on his blog...
I will be with Tony Querio, US Roaster Champion, later this month. I will ask him what he might be willing to share on a public forum. He roasts on a vintage '50s Probat.

http://dailycoffeenews.com/2016/04/20/t ... ny-querio/
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Boldjava (original poster)
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#20: Post by Boldjava (original poster) »

treq10 wrote:When I read that post, a couple of points came to mind:
...
5. The end goal is not to hit these subjective metrics. Rather, the aim is to roast coffee that is as delicious as possible to the person tasting it. Which means that these are guidelines rather than law.

Just things that came to mind while reading...

+1 many times. Joe Marrocco always stresses not getting overly enamored with your profile. His test of the roast? "Does it make you smile when you drink it."
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LMWDP #339