Not a member yet?
Click here to register.

Forgotten your password?
Request a new one here.

Shoutbox

You must login to post a message.

allenb

11/28/2023 6:38 PM

Waltkurtz

allenb

11/28/2023 11:13 AM

yoshiod9

renatoa

11/28/2023 3:52 AM

, Choppin ?

allenb

11/27/2023 5:52 PM

JHCCoffee

renatoa

11/27/2023 6:46 AM

, Braumeister

Shoutbox Archive

Forum Threads

Newest Threads

Skywalker, the ALM c...
Wake Up Smart Home C...
Bellwether Roaster
Solid State Relay Qu...
Potential LOT of Bui...

Hottest Threads

Larry Cotton's 'w...	[62]
1lb FB hopper roa...	[33]
Bellwether Roaster	[27]
Apwollo 11 roaste...	[27]
Skywalker, the AL...	[26]

In Memory Of Ginny

Donations

Latest Donations
dmccallum - 10.00
JackH - 25.00
snwcmpr - 10.00
Anonymous - 2.00
Anonymous - 5.00

Users Online

Guests Online: 12

Members Online: 0

Total Members: 8,005
Newest Member: Waltkurtz

Oh no! Where's the JavaScript?
Your Web browser does not have JavaScript enabled or does not support JavaScript. Please enable JavaScript on your Web browser to properly view this Web site,
or upgrade to a Web browser that does support JavaScript; Firefox, Safari, Opera, Chrome or a version of Internet Explorer newer then version 6.

View Thread

Homeroasters - Home Roasting Coffee Community » THE ART OF ROASTING COFFEE » Roasting Coffee

Who is here? 1 guest(s)

Page 3 of 3: 1 23

Roast Color Nerdy Stuff
oldgrumpus	#61 Posted on 03/28/2023 11:14 PM
1/4 Pounder Posts: 188 Joined: July 25, 2012	Also, depending on where you are, there may be very inexpensive places to have the printing done. Where I live, Craigslist, Shapeways, 3dhubs, and others....


renatoa	#62 Posted on 03/29/2023 1:52 AM
Administrator Posts: 2727 Joined: September 30, 2016	Still I am confused about the usefulness of such methods... if they aren't able to tell you degree of roast during development, and tell you with enough precision: Drop ! 3, 2, 1 ... NOW ! Assuming the grounds measurement is reproducible enough... discussions on HB shows they aren't... will ask those following here, generically, not only the thread author : How reproducible are our roasts ? If we decide a roast give us the right Agtron, are we able to reproduce it within the same limits as the Agtron measurement ?


Piotrkurak	#63 Posted on 03/29/2023 10:18 AM
1/4 Pounder Posts: 64 Joined: March 01, 2023	Quote renatoa wrote: Still I am confused about the usefulness of such methods... if they aren't able to tell you degree of roast during development, and tell you with enough precision: Drop ! 3, 2, 1....... How reproducible are our roasts ? If we decide a roast give us the right Agtron, are we able to reproduce it within the same limits as the Agtron measurement ? I agree:too many variables to control for with too many solutions. Not easily feasible from an instrumentation techs point of view.even with computer control


oldgrumpus	#64 Posted on 03/29/2023 11:19 PM
1/4 Pounder Posts: 188 Joined: July 25, 2012	I think the confusion comes from the fact we sometime try to combine two different methods (philosophies). One uses degree of time in development phase. This method does not account for roast color. The other does not account for time in development, but prioritizes the color of the roast instead. What I have just said above is most definitely an oversimplification, which I am using to clear up the confusion. Getting into it deeper, you may want to look at this video. It has answered a lot of questions for me, and since using this recent change in roast philosophy, I've been getting better results. I'm speaking for myself. Others have their preferences. No right or wrong here.... I would agree with the notion that 80 percent of our priority should be color and 20 percent pre-first-crack temp inputs. Time in development is important too, but one can achieve the same color in development even though one can spend more or less time there depending on the rate of rise. Staying there longer will give the dreaded "baked" flavor, and speeding up too much will give more acidity and fruitiness, but going too quickly will end up with it's own issues. Minimum time after first crack 1:20, and mid point between first-crack and second-crack, about 3 minutes... which is where I'm dropping with excellent results. For those going for fruity, 1:20 is better. Main target is first crack at 9 minutes. Too much to say here. Probably already lost some of you reading this... sorry. https://www.youtu...U&t=6s Edited by oldgrumpus on 03/29/2023 11:32 PM


allenb	#65 Posted on 03/30/2023 8:32 AM
Administrator Posts: 3776 Joined: February 23, 2010	Quote I think the confusion comes from the fact we sometime try to combine two different methods (philosophies). One uses degree of time in development phase. This method does not account for roast color. The other does not account for time in development, but prioritizes the color of the roast instead. Interesting point you've made. In watching experienced roasters on mid sized shop drum roasters over the years, I was able to see what they used for sensory input to control this final stage of the roast. They knew from lots of experience about where to set the gas valve when getting near 1C. Most of them would have a sample tray of roasted beans and a good light for color reference and as soon as the first audible snaps of 1C started, they would start pulling the trier every few seconds. I think they were able to sense the rate of the cracking of 1C and could tell by how fast or slow the color was changing and by these two sensory inputs, knew when to end the roast for a given roast level. 1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana


Piotrkurak	#66 Posted on 03/30/2023 11:34 AM
1/4 Pounder Posts: 64 Joined: March 01, 2023	All well and good for a normal roast. But I like FC roast levels that usually don't go beyond FC+1:00. Tis why I got really interested in color as opposed to bean temp Edit: Did a 2:30+FC dark roast last week and the beans are pretty uniform. Did an 0:30 FC ane have 4 distinct and repeatable color variations throughout the sample Edited by Piotrkurak on 03/30/2023 2:50 PM


renatoa	#67 Posted on 03/30/2023 3:24 PM
Administrator Posts: 2727 Joined: September 30, 2016	Exactly, when development is less than a minute you have a wide range of hue across the bean mass. Good luck averaging something... Before your later edit, was curious to ask you haw do you handle that apparent non-uniformity characteristic of light roasts. Got the answer


ACEMBL	#68 Posted on 03/31/2023 3:47 AM
Newbie Posts: 28 Joined: February 04, 2020	Interesting indeed. Good shout about the variance shortly after first crack. Here are a couple of my thoughts (for roasters with low inertia). As an indicator of, shall we call it ‘Rate of Colour Change’ I would propose continuous sampling with the data suitably filtered and averaged could give a good indicator of how the beans are responding to the roast chamber environment (temperature) over time. Where tracked against previous roasts data it would be good for warning where and how variables occur so adjustments can be made to compensate. For roasters with significant inertia (experience of 5kg drum) it could still provide useful data as to where the variation occurred but too late to not affect the result. The mix of human sensory inputs and knowledge of a skilled roast master would be incredibly complex to replicate, but surely a few tools to help mear mortals like me ‘see’ what’s happening can’t be bad 🙂 Just out of interest, for those that are more than hobbyists/ have friends in the trade, have you seen ColorTrack in action?


Yasu	#69 Posted on 03/31/2023 9:30 AM
1/4 Pounder Posts: 67 Joined: March 27, 2022	You mentioned roast collars on artisan's blog. https://artisan-r....html#more


Piotrkurak	#70 Posted on 03/31/2023 9:40 AM
1/4 Pounder Posts: 64 Joined: March 01, 2023	Hopefully renatoa's conclusion is that the color variation is the desired condition for the roast. Not sure what a low inertia roaster properties are defined as


oldgrumpus	#71 Posted on 03/31/2023 10:43 AM
1/4 Pounder Posts: 188 Joined: July 25, 2012	Quote allenb wrote: In watching experienced roasters on mid sized shop drum roasters over the years, I was able to see what they used for sensory input to control this final stage of the roast. They knew from lots of experience about where to set the gas valve when getting near 1C. Most of them would have a sample tray of roasted beans and a good light for color reference and as soon as the first audible snaps of 1C started, they would start pulling the trier every few seconds. I think they were able to sense the rate of the cracking of 1C and could tell by how fast or slow the color was changing and by these two sensory inputs, knew when to end the roast for a given roast level. Yes. Like this one. Put your target color sample in the middle of the tray and pull out samples until you have a color match. He talks about this being a good way to achieve consistency. If the pros do it, it's good enough for me. And it's simple... not overly nerdy, but practical. Think I'll try to find one. Clever Coffee Dripper Grinder: Macap M4 Roaster: Completed drum roaster project photos shown here: Photos https://goo.gl/ph...Da6K4wfqw5 Videos https://www.youtu...Bd1NrdpSUH


ACEMBL	#72 Posted on 04/01/2023 8:01 AM
Newbie Posts: 28 Joined: February 04, 2020	Quote Piotrkurak wrote: Hopefully renatoa's conclusion is that the color variation is the desired condition for the roast. Not sure what a low inertia roaster properties are defined as Colour variation is inevitable because no two beans are ever the same and the path any one bean follows throughout a roast will differ too. It will exist in all degrees of roast, it’s just whether the human eye can resolve it. For me, the whole point of this thread is to do with our inherent weakness resolving shades of brown? Sorry, those with ‘low thermal inertia’


Piotrkurak	#73 Posted on 04/01/2023 11:00 AM
1/4 Pounder Posts: 64 Joined: March 01, 2023	I thought the purpose was real time correlation of color to roast termination controls.

Page 3 of 3: 1 23

Jump to Forum:

Similar Threads

Thread	Forum	Replies	Last Post
Roast Color Meter	Building Other Coffee Equipment	5	10/08/2023 8:44 AM
Renatoa can you walk us through a roast based on Heat power control vs PID?	Roasting Coffee	32	08/21/2023 12:41 AM
Roast Color Meter - Build Offer	JAVA TRADING COMPANY	2	08/05/2023 3:20 PM
Bean roasting times and color	Roasting Coffee	2	05/25/2023 12:40 PM
New with Hottop roast profiles, flavors are unimpressive.	Roasting Profiles	20	05/06/2023 1:44 AM