Roasting coffee with "evenness" as the goal - Page 2

#11: Post by **keno** » July 17th, 2018, 3:16 pm

I haven't read Perger's piece on this, but if your objective is to improve evenness then it seems like a drum roaster would be better than a fluid bed roaster.

As Scott Rao has noted the technique to get an even inner and outer bean temperature is to start with high heat to penetrate the density of the green bean. Drum roasters allow you to charge at a high temperature whereas a fluid bed roaster doesn't. Second, and relatedly, the preferred form of heat transfer early on is conduction to take advantage of the moisture content of the bean to get the heat to penetrate to the center. If you hit it with lots of air early on you can strip away the surface moisture which will actually prevent this from happening (by prematurely drying the exterior of the bean you effectively create a layer around the bean that insulates the interior). This is why roasters often start with very low air for the first few minutes of the roast.

July 17th, 2018, 7:06 pm

I just did this roast:

The RoastRite color numbers are 48/48. Can't get much more evenly roasted than that.

July 17th, 2018, 7:15 pm

DaveC wrote:I suppose it's interesting to understand why you believe he is right.....do you have a lot of roasting experience on different types of roasters, do you understand the methods by which many drum roasters transfer heat, why would you think an absolutely even roast can be right on a variable product?

I don't need to drive a dump truck to reasonable assume it is slower than a Porsche.

Sorry for the snarky reply, but snark begets snark.

And if you would bother to read my OP, I am not claiming that an even roast is right on a variable product. I'm just stating what MP said and putting out here for discussion, with full expectation of some knee-jerk reactions like yours.

I'm not convinced MP is correct that maximum extraction is best...always, either. But now that I have a color analyzer, I can cup accordingly and come to my own conclusions, a lot like I did with Scott's declining RoR claims.

There is a whole lot of information on the internet. Unfortunately, a lot of it is hyperbole or plain dead wrong. But we read it and repeat it until somehow it becomes true by repetition.

Equally unfortunate, eloquence is often confused with real knowledge.

#14: Post by **DaveC** » July 17th, 2018, 8:23 pm

Almico wrote:I don't need to drive a dump truck to reasonable assume it is slower than a Porsche.

You don't, but if someone is telling you stuff about dump trucks, it's useful to have significant experience of a few different types to put their comment in some proper context.

#15: Post by **jammin** » July 17th, 2018, 10:10 pm

Matt Perger shills Super-Autos now too. Time to sell your Monoliths & LM's.

"You put the beans in here & yummy comes out here". ... this guy is no longer relevant IMHO

#16: Post by **crunchybean** » July 17th, 2018, 10:45 pm

I thought the Perger piece was very nice, thanks for sharing.

#17: Post by **themusgrat** » July 18th, 2018, 10:15 am

From what I can tell, the only thing that sets these supposed authorities on roasting apart, is that they don't ruin a lot of coffee. I bet that if you really wanted to extract the best flavor out of a bean, you'd need to have a bunch of different roasters on hand, and experiment with dozens of batches per roaster.... We all know nobody has this or does that.

Anyways, Keno brought up good points, especially about high airflow stripping away the outer moisture, which should actually be inhibiting the transfer of heat to the center of the bean, tending to scorch the outside.

A lot of things are great in theory, but in practice, a lot of people are using a lot of roasters to make great coffee. I'd think that each roaster has its weaknesses, and you learn to mitigate that with temperature ramp up and airflow. I'm talking out of my behind on this, only ever having used 1 roaster, but I just don't think anyone who tries to say "my way is by far the best" is really interested in finding the best thing, but more of interested in being thought of as the best. A lot of monks spend way more time being a monk than anyone does roasting coffee, and you don't see too many saying "im the best monk."

I guess coffee is not spirituality, so whatever, bad analogy, but the more hobbies I get into, the more I see people telling others the right way, and there is just not 1 right way to do just about anything, other than reload the toilet paper holder. It goes down, unless you have cats.

#18: Post by **DaveC** » July 18th, 2018, 10:34 am

themusgrat wrote:From what I can tell, the only thing that sets these supposed authorities on roasting apart, is that they don't ruin a lot of coffee. I bet that if you really wanted to extract the best flavor out of a bean, you'd need to have a bunch of different roasters on hand, and experiment with dozens of batches per roaster.... We all know nobody has this or does that..

I did at one time have 2 roasters a Hybrid fluid bed 1kg (Gene cafe CBR 1200, modded for power control) and a drum roaster 1kg. There were differences between the two in terms of roasting. For a few beans the Gene was better (but it was modded), for most of the roasts the Drum roaster was better.

The Gene was much easier to use for the unskilled operator, the drum roaster required more skill, but was capable of rewarding it. I used a 25kg 60s Probat when MP was probably just out of grade school and I would say that roasted pretty evenly and produced fabulous coffee. I do see large fluidised bed roasters in commercial operations sometimes, but usually so they can roast massive amounts of coffee fast and then water quench it so it don't catch fire. Most of the best roasters seem to use drum roasters and I feel sure if the results of FB roasters were better, those would be in the majority...but they are not.

Of course I have only been roasting for almost 15 years and only used 10 different roasters and only 5 of those proper commercial jobs.......so I am still very new to it...These authorities perhaps need to roast for a little bit longer and get a bit more experience of different roasters before making quite sweeping statements.

P.S. Super high airflow isn't usually a friend to roasting coffee and never seemed to get the best out of dry processed, or pulped natural etc.. beans

July 18th, 2018, 2:15 pm

DaveC wrote:. I used a 25kg 60s Probat when MP was probably just out of grade school and I would say that roasted pretty evenly and produced fabulous coffee.

When MP is talking about evenness, he is not talking outer bean to outer bean. He is talking about outer bean to inner bean. Did you ever use an Agtron (or similar) on your Probat beans to compare the inner and outer color?

I would love to see roast profiles published with corresponding Agtron data from various roasters. That would be very educational.

Without data, this is all just supposition and conjecture.

July 18th, 2018, 2:19 pm

No, I cut em open with a stanley knife, the Agtron tiles stayed in a cupboard along with other stuff that wasn't very useful. I don't really know your experience because although I asked you have not said.. So it's difficult to comment on what would be educational/useful for you and tricky to put any weight on what you think is supposition and conjecture.

I have actually done a lot of roasting...but I am not sure what it is you have done. So I will sign out of the thread as I don't think I will get anything useful from it.