There are those of you that have a heavy investment in their cooling apparatus. Some with actual cost and some with their design labors. Warning! Warning! Warning! - if you are one of those - DO NOT READ FURTHER!!! You are WAY too invested in your own devices and something as simple as this cannot POSSIBLY work. But for the rest of us .... Cooling beans is NOT brain surgery but a LOT of people seem to misunderstand the process. Air is an insulator NOT a conductor. Blowing it across an object(beans), really does a lousy job of grabbing heat way from the object. Colanders in fact are pretty bad because you are cooling the outside of the batch quickly but still letting the inside roast away. A MUCH better approach is to place the hot object into contact with a conductive material with as much thermal mass as possible (think of falling into 33F/0C degree water rather than standing in 33F/0C degree air). Hence the 'fan' approach to cooling is REALLY not the best approach at all. A MUCH more effective cooler would be a couple heavy aluminum half sheet baking pans (think Costco or Sam's). Simply dump the newly roasted beans onto the first pan for 30-60 seconds and then dump them from there onto the second pan. The heat from the beans will be VERY quickly given off by direct contact with the heavy metal backing sheet and the roasting process will be arrested very quickly indeed.http://www.amazon.com/exec/obidos/tg/detail/-/B0001MS8BK/102-6261498-5942561 Been using this process for many years and most professional cooks use this method for quick Cooling of confection and products. The CPU of the computer you are now using is cooled this way also. There is a heavy aluminum heat sink that is grabbing heat away from the CPU and throwing it into the air. Oh yes, there are fans in there too. But that's because you leave your computer on continuously (unlike cooling beans which only takes a few minutes). The fans are only there because the heat sink cannot be made big enough and still fit in the case and at a certain point, fans are cheaper to carry away the residual heat than heavy aluminum heat sinks are. Water cooled engines are better at removing heat than air cooled ones. We could go on and on. Its greater thermal mass that counts, not strainers and colanders with all their holes and limited mass. Its just the simple laws of thermodynamics. Now, having said all that, it is my humble opinion, that much like fine scotch whisky (without the 'e') is a blend of the various nuances of several Inslay malts as well as others, Coffee benefits from being a BLEND of several different roasts of the same beans (or others as well). I often mix a full city with a good minute past second crack roast of the very same beans in a double batch and therefore get the high notes of the full city with all the deep chocolaty and nutty/earthy taste of the French roast. Shall I go on ?
With the caveat that for even better cooling use copper not aluminum. (the most efficient cpu coolers are copper not aluminum;-) MM
What sized pans are you using? What sized roast are you cooling this way? My skillet and my drum do about 2-3lb per laod - do you envision this method working with this sized load? Thanks, Brett On Tue, 22 Mar 2005 10:53:30 -0600, jeremy wrote: <Snip> -- Regards, Brett Mason HomeRoast __]_ _(( )_ Please don't spill the coffee!
On Mar 22, 2005, at 10:53 AM, jeremy wrote: <Snip> I have a 22" x 24" x .5" steel slab for the griddle on my kitchen range. I spread the hot beans on it and stir them around a little and they are cool in less than 2 minutes. Obviously I don't roast when I'm cooking on the griddle. Jim Gundlach "The espresso machine is an accessory to the grinder, not the other way around."
Jeremy.. hehe I have been using this for about 2 years.. Ive posted my site a few times...lol it DOES work I attest! I roast about 4oz to 7oz.(1 cup) in modded original poppery and 1 1/2 - 2 cups in volume with my Turbo Crazy.. I have a little walmart turbo fan that sits on side and sometimes I pick it up and shake pan... here is my site again.. These are last years old pics... hehehttp://homepage.mac.com/dparham_is/.Pictures/Photo%20Album%20Pictures/ 2004-08-23%2020.49.42%20-0700/Image-E665EC7CF57F11D8.jpghttp://homepage.mac.com/dparham_is/PhotoAlbum14.htmlDennis Parham On Mar 22, 2005, at 10:53 AM, jeremy wrote: <Snip>
Wow Dennis a fan and a pan too cool your beans. It isn't like you to overdo things. Jared On Tue, 22 Mar 2005 14:26:03 -0600, Dennis Parham wrote: <Snip>
This is a multi-part message in MIME format. Not to keep beating a dead horse , but I think air cooling is just fine. For several months now I have been using a hand held hair drier. One of those Pro 1800 watt jobs with the cool air only option. I leave the beans mixing in my Turbo Beast and point the hair drier at them. Just have to be careful not to blow the beans out of the roaster. Have to be careful not to cool them too quickly, usually try to get down to 160 F in about 2 - 3 minutes. This cost me $3.00 in a thrift store. Well, I have not figured a way to catch the chaff yet, nor have I even thought about it. Somehow I love to see the cloud of chaff block out the sun ;-) Well, not really, but there is a LOT of it, and eventually the wind takes it all over the neighborhood. Or else I have to just vacuum it up :-( PeterZ Adding his 1.5 cents from here in LHC. Linux-by-choice wrote: <Snip>
"With the caveat that for even better cooling use copper not aluminum. (the most efficient cpu coolers are copper not aluminum;-) MM" Oh YEAH Baby! Show me the website that has $6.90 Heavy COPPER half size backing sheets and I'll be there in a heartbeat! :-) And why stop there ? Silver is a better conductor than Copper. And Gold is better than either. And then there are superconductors and all that Kelvin talk ... :-) Shall I go on ? LOL
This is a multi-part message in MIME format. Pop Science - I love it. Cooling fins only work if there is a seal between the heating object and the fin - silicone grease. Hey a use for oily beans! The newest cpu has a coupler for "an air hose" built onto it. Those physics freaks in Silicone valley never pay attention. The fastest thermal exchange seems to be from a ventilated metal tray with air blown up through it and a stirring rod The metal tray is cold - and it is ventilated so the air can move through the beans as they are stirred. But for really fast cooling you might want to try a shot from a CO2 fire extinguisher! Well, truth be told, silicone grease is an insulator too. Its the Zinc Oxide or other metallic particles that is IN the grease that acts to fill in the surface imperfections in the metal to metal contact of the two, thus increasing conductivity. Tthe silicone just makes it easy to disassemble and prevents it from caking up and flaking away. If you could somehow make them perfectly flat, parallel planes with no surface imperfections, you would not need the grease at all and it would actually be a hinderance. If the beans on the tray somehow continued to generate heat like a CPU does, then a fan would be helpful. But they don't. The fastest method will ALWAYS be a solid mass with the most surface contact. Vented fins attached to a SOLID conductive sheet in contact with the heat source is a common method (but never a ventilated sheet/tray making the contact). Theoretically, if there was a conductive liquid poured over the beans in the pan thus conductively connecting the beans more fully to the pan, THAT would be superior, but I haven't yet fiured out what THAT liquid would be :-) Your CO2 suggestion kinda touches on it though. The CO2 actually being in a point between a liquid/solid and a vapor (evaportion/sublimation) In cooling, fans are just used for the economy of not having to use as much expensive thermal mass (conductive metal usually) to keep heat levels below a certain threshold. The end product is that it without using a thermal mass, it would take a REALLY big, fast and expensive fan to sink the same amount of heat in the same amount of time as an inexpensive solid conducting mass like aluminum. And then you'd have to be able to handle the chaff blowing all over the place too :-) Shall I go on ?
This is all well and good but the problem is getting the beans into = contact with the metal sheet. My guess is that most of the heat passes = from the beans into the sheet via a fluid - air. The beans do not have a = flat surface to contact the sheet. Phil
Let me see...on a hot day, do I want to be cooled with a fan or to be placed between two metal sheets... ********************* Ed Needham "to absurdity and beyond!" ed at homeroaster dot com (include [FRIEND] somewhere in the subject line of any email correspondence) *********************
On Tue, 22 Mar 2005 10:53:30 -0600, jeremy wrote: <Snip> I roast in the oven, usually 1-2 lbs at a time, on half-sheet pans. I used to cool using exactly the method you describe, using three half-sheet pans in rotation. I use a box fan and drum sieve now. Cost me about $30 total, but I can use both of them for other things and I can cool 2lbs of beans to room temperature in < 5 min. ... <Snip> I'm not sure how much credence I should give to someone who pointedly corrects the spelling of whisky but then immediately misspells "Islay." So - I've tried both methods, I prefer a fan, and I like my Islays cask strength and unblended. Chacun a son gout. -- Charles
I used to sometimes dump out my roast onto a marble counter. It worked pretty well, at indoor ambient temps. There's merit to the heat sink technique, but moving air seems to capture enough heat, at a good enough rate, so that it works very well. I vote for a huge slab of copper with refrigerated air blowing up through tiny holes, like on an air-hockey table. That seem to be the best of both worlds. <Snip>
With PID control.... On Wed, 23 Mar 2005 14:16:16 -0500, David B. Westebbe wrote: <Snip> -- Regards, Brett Mason HomeRoast __]_ _(( )_ Please don't spill the coffee!
I vote we PID Brett's email comments. Jared On Wed, 23 Mar 2005 11:48:33 -0800, Brett Mason wrote: <Snip>
David B. Westebbe wrote: <Snip> Hey, if you epoxy the pucks, you could play espresso hockey!
jeremy wrote: <Snip> But you clearly understood my point. The application of silicone grease is a requirement. You may go on, but pardon me if I seem to have lost interest. You seem more bent on your exhibition of pop science than an objective answer to the question posed. John - truly in the curmudgeon mode now!
Of course, you are indeed correct (smacks forehead) You got me! - too much Islay that night .... But you'd have to know me a little better to know that I NEVER deserve much credence. :-) To all you Fan Cooler Fans out there, a fan is perfectly fine, I was really just talking to someone that might be contemplating an "upgrade" to a fan. Its just unnecessary IMHO, you can do as well with what most kitchens already have (aluminum sheet pans), without buying a special fan, hauling it out, plugging it in, listing to all its noise and chasing the chaff. And I really doubt that the difference between cooling in 30 seconds vs a minute or two really makes any difference anyway. Its so far off the roasting temp after 30 seconds using either method that it hardly matters - IMHO of course. ================ I'm not sure how much credence I should give to someone who pointedly corrects the spelling of whisky but then immediately misspells "Islay." So - I've tried both methods, I prefer a fan, and I like my Islays cask strength and unblended. Chacun a son gout. -- Charles
"One man's fish is another man's poisson." Safe Journeys and Sweet Music Justin Marquez (Snyder, TX)http://www.justinandlinda.com Deja Moo: The feeling that you've heard this bull before. On Wed, 23 Mar 2005 10:37:15 -0800, Charles Haynes wrote: <Snip>
Picking up on PeterZ's dead horse and chaff all over the neighborhood: pouring the beans between two colanders in the air from a small clip on fan cools my 600gm roasts in about 2 minutes and makes the chaff available to the neighborhood instead of my brew. owen On Tue, 22 Mar 2005 14:36:03 -0700, petzul wrote: <Snip>
On Mar 29, 2005, at 1:21pm, owen cox wrote: <Snip> I wouldn't want to have to clean up that mess. John Blumel
I sweep the chaff over to my compost pile... Other pieces landing i the grass just make the distribution that much quicker... Brett On Tue, 29 Mar 2005 13:39:22 -0500, John Blumel wrote: <Snip> -- Regards, Brett Mason HomeRoast __]_ _(( )_ Please don't spill the coffee!
I thought he meant the horse. <Snip>
On Mar 29, 2005, at 2:05pm, Brett Mason wrote: <Snip> What do you do with the pieces of the dead horse that are scattered about. John Blumel
feeds the [civet] cats Bob - bee'less in Parker
We just keep kicking the dead horse... Has worked for most email threads on the list so far... Brett On Tue, 29 Mar 2005 14:59:33 -0500, John Blumel wrote: <Snip> -- Regards, Brett Mason HomeRoast __]_ _(( )_ Please don't spill the coffee!
OK, I like Bob's answer better - we use the horse to feed the cats ... ... ... I don't know why she swallowed the fly - perhaps she'll die. Ah, campfire songs... and a cup o Joe! Brett On Tue, 29 Mar 2005 13:52:30 -0700, Bob wrote: <Snip> -- Regards, Brett Mason HomeRoast __]_ _(( )_ Please don't spill the coffee!