HOMEBREW Digest #2754 Tue 30 June 1998

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		Digest Janitor: janitor@hbd.org
		Many thanks to the Observer & Eccentric Newspapers of 
		Livonia, Michigan for sponsoring the Homebrew Digest.
				URL: http://www.oeonline.com

  Re: Roller Mill Spacings (again) ("Ludwig's")
  Winemaking (Tom Clark)
  TEC cooler (Poris)
  Hops variety/miscellany (Joseph.M.Labeck at brew.oeonline.com, "Jr.")
  Industrial .vs. medical O2 ("Hans E. Hansen")
  Misc questions & comments ("Hans E. Hansen")
  RIMS Heat exchanger (ZIMURGIST)
  RE: Charlie P. Scandal (Doug Kerfoot)
  Keg fittings, Open Ferment (droot)
  Open sea Fermenting ("Jerry Holcomb")
  Dry Tripels (Tom Wolf)
  alternative for casks? (Tom Alaerts)
  Is 212 F steam hotter than 212 F water? (william macher)
  Roller Mill Spacings (again) (Jack Schmidling)
  salt (Paul Mahoney)
  RE:Oxygenation (NEWTRADBC)
  Color I (AJ)
  Color II (AJ)
  Dry Beer (Kyle Druey)
  RIMS Does Not Require a Thin Mash (Kyle Druey)
  End of my career as a brewer? ("Michael Kowalczyk")
  re: Citric beer (John_E_Schnupp)

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---------------------------------------------------------------------- Date: Sat, 27 Jun 1998 00:05:08 -0400 From: "Ludwig's" <dludwig at us.hsanet.net> Subject: Re: Roller Mill Spacings (again) Ok John, now you've gone and made me secure my beer, get out'a my chair and get this info for you. You owe me dude.;) First off, I'm using a roller mill with two counter-rotating, 3 inch dia, 8 inch long, smooth, concrete rollers. Only grain I've milled is Briess 2-row and my best setting is about 0.032 in roller spacing. My mill design allows adjustment on the fly so I've played around with it pretty much every time I do a batch. This spacing gives the best results. Not sure how this spacing would work with those mills with skinny/narly rollers. Dave Ludwig Flat Iron Brewery SO Md Return to table of contents
Date: Sat, 27 Jun 1998 07:50:41 -0400 From: Tom Clark <rtclark at eurekanet.com> Subject: Winemaking Does anyone out there know of a forum similar to HBD that deals with the art of making your own wine? Is there significant risk in using my beer making equipment to make wine? Will it still be OK for making beer? Many thanks E-Mail welcome... Tom Clark Return to table of contents
Date: Sat, 27 Jun 1998 11:16:15 EDT From: Poris at aol.com Subject: TEC cooler Thanks for all the input on my idea for a TEC fermentation controller/cooler. The consensus was that their performance is marginal for this application and the expense was excessive compared to used refrigerators. I tried to avoid using a large, heavy refrigerator in the basement (my basement is down a hill) but maybe this is the best compromise. Maybe a TEC 1 cubic foot yeast starter or a single 12 oz bottle controller :) Thanks, Jaime (finally warming up in the Santa Cruz Mountains) Return to table of contents
Date: Sat, 27 Jun 1998 12:2:59 +0800 From: Joseph.M.Labeck at brew.oeonline.com, "Jr." <joe-sysop at cyberbury.net> Subject: Hops variety/miscellany (Let's see if I can get this right) I come before the gods of Homebrewing on bended knee, a most unworthy extract brewer, to place my ignorant question on the altar of the HBD. (Gosh, I feel like I'm writing to the Usenet Oracle.) Anyway, sometime ago I had posted with a few questions. Most of them were taken care of, but this got lost in the shuffle. I had ordered some hops from a mail order garden supply shop. When I asked them the variety, they replied "Oregon Golden Nugget". Anyone faniliar with this? Private e-mail fine. On another issue, I've been reading the Digest faithfully for about 5 years. George, George, Al, Rob, Dave, and many others, have all been very helpful, and patient. I got a lot of information I needed when I was very new at this. I still get a lot. Although I have no all-grain ambitions, I find it interesting to know what goes on in the mash. Some stuff bores me, but I'm told I do, too. One last thing: Sam Mize writes--- >Personally, I'd say if it's brewed at home and not for sale, >it's homebrew. That's a definition that some contests have used, >to allow for the private >work of professional guys like Jethro and George Fix. However, >this does put a small homebrewer at a disadvantage compared to >someone with analytical lab equipment and professional experience. I'm curious...Why would I be at such a disadvantage, just because I'm only 5'5" and 115 lbs? Hmmm, that twice I've posted in the same year. How many more before I'm a "regular". Joseph M. Labeck, Jr. Joe's Beer - Featuring Cuppa Joe Stout, Nut "n" Tuit Brown Ale, Nothing Special Bitters, Uncle Bill's Porter, and Born To Be Mild Ale Return to table of contents
Date: Sat, 27 Jun 1998 10:10:36 -0700 From: "Hans E. Hansen" <hansh at teleport.com> Subject: Industrial .vs. medical O2 Al K. wrote: Same oxygen. The only difference between medical grade and industrial grade oxygen is that you need to drag around a stack of paperwork on the tank that *holds* the oxygen in the case of medical O2. I've read (here in HBD) even that some medical oxygen has anti-fungal agents added, but have not seen it confirmed by anyone. If that is indeed true, medical grade would be worse. <end quote> A medical O2 salesman once told me that industrial (i.e. welding) O2 is actually more pure than medical. He said that the medical grade can give spots in welds (carbon?). Obviously, whatever impurities are in medical grade must be in minute quantities and harmless to both us and, most likely, yeast. Anti-fungal agents would be a different matter, tho. A few sniffs of the O2 from the welding setup sure helps a hangover (not that I would know). Just be sure to turn off the acetylene. Hans E. Hansen hansh at teleport.com Return to table of contents
Date: Sat, 27 Jun 1998 10:57:16 -0700 From: "Hans E. Hansen" <hansh at teleport.com> Subject: Misc questions & comments A couple of questions and a comment: 1. I have recently went to grain brewing and am having a difficult time acheiving the proper mash temp. The specifics: 5 gallon Rubbermaid cooler, small batches using ~4 lbs or so grain. Using a single infusion of 1.25 qts/lb, Brewers Workshop software says to use 172 deg water to achieve a 158 deg mash (you'll see why I use such a high temp in a minute.). Also note that I have to use an extra qt because of the Phalse bottom. When I do this and mix, I end up in the low 140's. Two more quarts of boiling water are needed to get me up to the low/mid 150's. It appears that I need strike water at around 180 or so to do it right the first time. What gives? (p.s. - I have checked the thermometer.) 2. Sparging and HSA - Is HSA a concern when using Phill's Sparging Sprinkler? It looks like this aerates the sparge water a lot. Also, I have to use ~200 deg sparge water to acheive 170 going into the cooler because the sprinkling action cools the water A LOT. =============================================================== Comment: A few weeks ago there was some talk about homemade crystal malt. I tried it and have a few notes of possible interest. Nothing original here, these thoughts were expressed by others in the original posts. Sorry that I have lost the names of the originators. 1. Try it. It's really quite easy. 2. I found it nearly impossible to achieve adequate temperature control in the oven for the mashing stage. If I set my oven to 140 deg, it would turn on at 140 and heat to about 190 before it would turn off. Then slow cool to 140, repeat. Someone suggested a CrockPot. Good idea. I set mine on low. After an hour or so, it was at 160 deg. I turned it off and let it sit for another hour where it fell to the high 140's. I felt this was probably adequate. 3. Don't roast at too high a temperature. I was in a hurry and turned up the oven to 300 deg to dry/roast. The grains around the edges of the cookie sheet got quite dark, the ones in the center stayed much lighter. i.e. - not consistant. I think a slow roast in the low 200's with occasional stirring would work fine. 4. Getting consistent results (concerning color) should be obtainable with simple experimentation. Keep quantities, equipment, and temps the same, and just vary roasting time. 5. Results? My Ordinary Bitter currently has 1" of foam on it, so I can't speak about flavor. Hans E. Hansen hansh at teleport.com Return to table of contents
Date: Sat, 27 Jun 1998 16:58:26 EDT From: ZIMURGIST at aol.com Subject: RIMS Heat exchanger Greetings to the collective, I've read much concerning RIMS heating elements, etc while lurking recently. I've used a RIMS sytem with electrical element for about 5 years. I've tried a 3800, 4500 and 6000 watt LHD element. I think RIMS is great for 5 gallonb batches, but when using grain bills of 20# or greater, I found the element unable to make the next temp boost in a reasonable time frame. I thought about using an external heat source, but did not due to concerns about scorching. I ran across a RIMS website that used a heat exchanger made of 1/2" Cu coil inside the sparge vessel.This seemed to make sense as some home heating systems utilize the H2O heater to run water through a coil which the furnace forces air over. To make along story short I retrofitted my converted keg system to include a 20' Cu coil in my sparge tank. I mash with 1.5 qts/lb of grain and have no problems with complete conversions at 150F for 60". Temp boosts are fairly rapid with 170F H20 in the sparge tank (135->150 in 5-7") I used1/2 comp-1/2 MNPTss Swagelok fittings with ss washers and teflon string(5/32 faucet packing available at any hardware store) on the inside screwed into a 1/2 ss ballvalve on the out side. Teflon is good to +400 F according to the label. The website that was my inspiration is www.pressenter.com/~rcalley On a different note- has anyone tried a small fermentation with lactobaccillus to be pasteurized and added to a Belgian wit for acidity/tang? I saw a posting in the archives for some sour mashing procedures using yogurt, grain or sourdough starter, but as I understand any acid tangy adjustment must be post boil. I've thought inocculating a batch after fermentation and monitoring it's acidity then flash pasteurizing by immersing a corny keg in 160-170F H2O to stop bacterial action. Anyone been daring(crazy) enough to try this? Cheers, David Schmidthuber Zimurgist at aol.com Return to table of contents
Date: Sat, 27 Jun 1998 18:07:14 -0400 From: Doug Kerfoot <dkerfoot at macatawa.org> Subject: RE: Charlie P. Scandal Rick Theiner wrote: >Shocking stuff!! There is truly an amazing likeness, and I wouldn't put >it past Charlie P., but there seems to be a subtle difference that I >can't put my finger on. >You've got some frightening pictures, Doug (but fun!). Thanks Rick, I will make the assumption that the frightening pictures you mention do not include the times that my face has been on the beer cam! ;) Does anyone have any ideas for the beer cam? I mean now that I have one, I should try to find a use for it, eh? To date all it has proved useful for is to allow me to observe how bloodshot my eyes get by my third glass of Pils. Well, that and to provide free advertising for the Unibroue folks. It was suggested that an air-lock cam would be more entertaining than a fish cam. I agree and will probably point it at a carboy this winter, but I really don't want to stick the cam in my fridge and don't want to drink a beer fermented at 85 F! (Now, the cam in the fridge would answer the age old question though, wouldn't it?) -Doug http://www.macatawa.org/~dkerfoot/ Return to table of contents
Date: Sat, 27 Jun 1998 16:51:17 -0400 From: droot at concentric.net Subject: Keg fittings, Open Ferment I am a welder, and I do play one at work (sometimes). I do not use a welded fitting on my converted kegs. I use plain Pipe fittings. I just buy a 1/2" ball valve with a male thread 3/8 pipe, and some flat washers. I try washers on the male pipe threads until I find one that fits. Metric flat washers fit better than American. I then use a female pipe thread/compression fitting on the inside. The washers take up the space, and sandwich the thin stainless keg in between them. This makes cleaning a breeze, because it can e taken apart at any time. I then can install any type of copper tubing that I prefer on the end. I use a piece of 3/8 copper tubing bent like a ? for my mash tun manifold. I use a short piece of plain copper tubing (3/8) for my boil kettle. I use a 90 dagree elbow for my HLT, pointed down. Open Fermentation. I use it. I ferment in an open converted sanke keg. I usually Use Wyeast 1007 German ale yeast. The cooled wort is drained Into the keg, and the LARGE starter is pitched into the wort. I ferment in my basement for about 6 days. I then drain the BEER out from under the yeast. The yeast is still in the fermenter In a pancake on top of the beer so it stays on top and does not End up in the corny keg. Never an infection, and always great Homebrew. By the way, A Plasma cutter is the only way to cut the top Out of a sanke keg. Anyone in the Lockport Area, I will cut them for a homebrew or two. Email if you have any questions. Return to table of contents
Date: Sat, 27 Jun 1998 20:34:36 -0700 From: "Jerry Holcomb" <eagle at teleport.com> Subject: Open sea Fermenting >Here is one I doubt anyone has seen on the HBD before. >A friend of mine plans on living on a yacht once he retires. He questioned >me about the >possibility of brewing on his boat. **SNIP** The use of a corny keg with a pressure valve set low (say 5lbs) should do the trick just make sure that it is firmly secured to the boat. Don't need a heavy tank slamming around a pitching boat. Return to table of contents
Date: Sat, 27 Jun 1998 20:39:05 -0600 From: Tom Wolf <wolfhrt at ibm.net> Subject: Dry Tripels Some more discussion: Al K don't take offense to my style I am a slow typer and this style without the long lead in moves fast. I would love to learn more about this subject! Al writes: "Firstly, I don't think that Tripels are dry. I think they are medium sweet." Yiikes! It looks like I have to do some more Liquid research starting with a Westmalle trippel. I have had this same discusion with other revered brewers and got the "It was the liquid bread ,therefore it is supposed to be sweet" answer. My judgement is that the homebrew and microbrew tripels tend to be overly sweet but that best Belgian examples have a much more balenced dryness. Al writes: "Secondly, I don't agree that the yeast will necessarily be "ruined" by the additional sugar." Yeasts that have fermented a wort of gravity much past 1.068 are pretty much 'toast' from the standpoint of pitching into a new beer of any strength. I would imagine that they would have a problem of finishing a 1.080 wort. I think that pitching lots of yeast is just moving farther out on a log curve of attenuation capabilities. The returns are diminishing and it takes a ton of yeast! Al's Three words: "alcohol is sweet." I say the opposite. Alcohol is drying. Try adding Everclear to an overhopped malty sweet IPA. It will be drier and more alcoholic. Not sweeter. I will try this experiment as I have both of the ingrediants. Cheers all! Return to table of contents
Date: Sun, 28 Jun 1998 14:57:29 +0200 From: Tom Alaerts <TomA at BUT.BE> Subject: alternative for casks? Hello gurus, You guys have been a lot of help for me already. I am sure my brews will reflect this! Here's yet another question: It is sometimes suggested to let some kinds of beer mature in wooden casks. For example, commercial Old Flemish Browns are very often aged this way. But I don't have a cask. So I thought, maybe I could just put a lot of "wood-spirals" (don't know the correct English word) in my plastic secondary fermenter. So I have a big surface of wood that's in contact with the fluid. I thought of this because the Californian Monterey Vineyard (owned by Coca Cola, I believe) uses a similar processus (while in France, it is a forbidden practice if you want a "Grand Cru blabla" nomination). In short, is this a good idea? Cheers, Tom Alaerts Return to table of contents
Date: Sun, 28 Jun 1998 08:56:44 From: william macher <macher at telerama.lm.com> Subject: Is 212 F steam hotter than 212 F water? Hi Dave and all, Just read Dave's ["Ludwig's" <dludwig at us.hsanet.net>] reply to my RIMS heating element sufrace temperature HBD question... A Sunday HBD is always a great surprise! Dave, I am certain what you stated about the surface temp of an electrical heating element vs flow rate is true. I was trying to get a reference temp for an element in a rims that was operating successfully/properly, to use as a base line for comparing to the temperatures that would be encountered with steam injection, as I think lower temperatures of steam is one of its chief advantages. >Also, the more I think about the steam idea. Is there any significant >advantage to injecting say a lb of steam at 215 deg and a lb of water at >212 deg? Yes. THere is a tremendous difference. I was so amazed by this fact that I decided to post what I learned to the hbd, and it turned out to be a three-part posting on the basics. I hope it conveys the necessary information. To make a long story short, when a pound of steam condenses and produces a pound of 212F water, during the phase change from vapor to liquid, that steam gives off amount of heat energy equal to six times the amount of heat required to heat a pound (pint) of water from 32F to 212F. That is a LOT of heat energy. So, the difference between steam and hot water at 212 F is tremendous! > If your injecting the steam through a nozzle in to the flow, >soon as it hits the flow, it will just be a dribble of hot water and >would take a lot of steam to heat effectively. Actually, your are correct in the first part. Steam on a weight basis, occupies 1600 times the volume of water. So a bubble of steam becomes 1/1600 of its size when it condenses and releases its heat content. The fact that it becomes a dribble, is to our advantage if we use it to heat a mash, for example. When it is all over, we do not really add that much condensate to the mash, considering the amount of heat that is carried to the mash by the steam. The second part of your sentence needs some clarification. Steam gives of tremendous energy when it condenses into water. Bottom line is it would take a lot of hot water to heat effectively, but not a lot of steam, since the transition(phase change) from steam to liquid is where we get most of the heat from. Suppose one were doing a simple infusion mash, and raising temp from say 155F to 167 F. If we had to choose between Steam and 212F water, we would find that it would take much, much more water( than steam, by weight) to accomplish this temperature rise. [A quick mental calculation tells me it would be about 90 times more water...of course, take this with a cup of salt...err...grain of salt?...I've just had one cup of coffee this morning :-)] Oh...back to the subject line... No, 212 F steam is not hotter than 212 F water. It just carries a much higher energy content, and when it condenses and gives off this energy, it becomes 212 F water! Amazing stuff, this steam, isn't it? Bill Bill Macher macher at telerama.lm.com Pittsburgh, PA USA Return to table of contents
Date: Sun, 28 Jun 1998 07:37:06 -0700 From: Jack Schmidling <arf at mc.net> Subject: Roller Mill Spacings (again) montgomery_john at ccmail.ncsc.navy.mil says: " I got ONE response (thank you Kyle Druey) to my question the other day regarding recommended roller spacing for different grains (barley vs. wheat vs...) using adjustable mills. Perhaps that says something about the crush mythology and more importantly, why our fixed mill is so popular with the grass roots homebrewers. "Does anyone know of a resource on the Internet? I've searched Real Beer and The Brewery. You need to search a "real" resource.... there has been an application note on "Crush Quality" on our web page for years. js - -- Visit our WEB pages: Beer Stuff......... http://ays.net/jsp Astronomy....... http://user.mc.net/arf ASTROPHOTO OF THE WEEK..... New Every Monday Return to table of contents
Date: Sun, 28 Jun 1998 13:45:41 -0400 From: Paul Mahoney <pmmaho at roanoke.infi.net> Subject: salt This is a request for a discussion on the use of salt in our homebrew. The June 27, 1998 issue of "The Economist" included an article(p. 88)on the production of malt whisky in Scotland. It reported that malt contains hundreds of individual components - alchohols, esters, acids, and phenols. All of the things we have come to know and love! I found the following quote interesting: "Scientists at the Scotch Whisky Institute in Edinburgh have experimented with adding salt to blended whisky barrels to make the spirit mature faster (having millions of barrels lying around for at least three years is the industry's biggest single cost). Not only did salt speed things up, its boosters say it enhanced the flavor, making blends more malty." I then checked S. Snyder's "The Brewmaster's Bible" (p. 84-85), and he said that the addition of Na contibutes body, full mouthfeel, and character. The addition of Cl brings out malt seetness and contributes to mothfeel and complexity. Too much Na will give a "seawater" taste. So how many of us add a pinch or one teaspoon of table salt to our wort? Will salt speed up our processes? Who does it, and does it improve your beer? Do you recommend it? Paul Mahoney Roanoke, Va. Return to table of contents
Date: Sun, 28 Jun 1998 15:07:32 EDT From: NEWTRADBC at aol.com Subject: RE:Oxygenation <From Tom Bergman as newtradbc at aol.com> I began using oxygen this year, and although I did not do a scientifically valid test, the results have been impressive in terms of quickness of fermentation and achieving final gravity. I noticed no visible consistent reduction in lag time (sometimes less, sometimes more), but I typically pitch a fair amount of yeast slurry (1-2L starter for ales, 3-4L starter for lagers). One particularly impressive example was a barleywine, used slurry from a 5L starter (which I make and pressure can myself if we want to restart the botulism thread!) with Wyeast 1056, and 3 minutes of oxygenation. Barleywine dropped from 1.106 to 1.022 in less than 7 days, and was reasonable bright and surprisingly smooth tasting for a one week old barleywine. Normal gravity beers tend to reach final gravities in 3 to 4 days, lagers sometimes a week. So I'd recommend it. I typically use 2 minutes of steady stream of oxygen per 5 gallon batch, done prior to pitching yeast. I have a friend in the compressed and liquified gas business, and she said there is a difference between medical and welding oxygen (in addition to the paperwork). Welding oxygen is not as pure (like 99% oxygen), but the impurities are other gases, principally nitrogen. There is NO contaminant like oil (because it would turn the oxygen bottle into a bomb). She suggested only getting welding oxygen since its much cheaper and the 1% other gas content is irrelevant to the homebrewing application. Return to table of contents
Date: Sun, 28 Jun 1998 19:34:01 -0400 From: AJ <ajdel at mindspring.com> Subject: Color I I don't recall exactly what I wrote about superiority or inferiority of various methods for measuring/describing/quantifying beer color but I didn't mean to boost or deflate any particular one - rather simply to note that there is no intepretation, judgement, fatigue or perception factor with the ASBC method or any other method based on spectrophotometry. Compare with the Lovibond system which requires, as I understand it, a visual comparison with standard glasses. The ASBC method (absorbance in a 1" cell at 430 subject to the turbidity check) is the ASBC's method, not mine. I'm sure that it is the result of much study (ASBC Report of the Subcommittee on Color in Beer, Proc. 1950 p 193 and ditto, Proc 1972 p140 are cited in the MOA - I've seen neither of these) and represents the best compromize in terms of quantifying beer color by a single number: a thing to be devoutly wished! I don't think it's perfect and neither, I'm sure, does the ASBC. Color is very much a subjective thing. Different folks perceive color quite differently from one other. I am an obvious and extreme example being color blind. At the other end of the spectrum, some people are known for having an "eye for color". In the remainder of the post let's look at how good the ASBC method is in terms of what I found in my refrigerator this Sunday afternoon. First, a little background to help you interpret the data. Lots and lots of work has been done in quantifying color. Without this color television would be impossible. The job of a tv camera is to measure the color of a pixel and transmit that data to the receiver. The receiver has to take the camera's measurements and produce light _that looks to the viewer like the object being televised_. The TV set doesn't exactly reproduce the spectrum of light picked up by the camera. It puts out light that makes you perceive as being the same color as if you were in the studio. The result of much cooperation between psychologists and engineers is the tristimulus response model of color based on the three sets of color receptors in our eyes. The model includes the response of each of these three receptors to light of various wavelengths for an average person and, based upon an average person's response quantifies color into three numbers. These numbers can be transformed into various coordinate systems depending upon the application (i.e. to encode them for transmission) but for specifying the color of beer (or any other liquid) luminance (brightness) symbolized by Y and a pair of numbers (x,y) between 0 and 1 which convey "chrominance" or color information are used. This system has other applications as well. The x and y numbers by themselves don't mean much but the distance of an (x,y) point from the point (x=0.32,y=0.32) gives an idea of the "purity" or "saturation" of a color and the angle of a the with respect to the positive x axis gives the "predominant wavelength" or "hue". With beer, the tristimulus responses (X, Y, Z) can be obtained by measuring the light which comes through the beer using tristimulus filters in a colorimeter of, if a spectrophotometer is used, by summing the transmissions in percent (_not_ log units) at 30 wavelengths (a different set of 30 for each of the three filters) and scaling the sums to produce X, Y, and Z. x and y are then simply x = X/(X + Y + Z) and y = Y/( X + Y + Z) (x,y) values are plotted on a so called chromaticity diagram from which the predominant wave length or hue can be read as can the saturation or purity of the color. This can, of course, also be done mathemtically. Thus what you will see, assuming you are an average person who fits the tristimulus model well, can be modeled by a set of three numbers: (Y,x,y) or (Y, predominant wavelength and purity). The latter set is more descriptive. So lets look at some beer. In the table which follows the beers are 1 and 2 Home brewed Bohemian Pils (yes, I know they are too dark but the judges haven't caught this yet!) 3 Homebrewed Bavarian Weizen 4 Potomac Mount Vernon Porter 5 New Castle Brown Ale 6 Prima (Victory's Saaz tea). These certainly don't represent the universe of beer but, as they are as random as what's in my fridge at any given time they can't be said to be a biased sample either. WRT the table columns: SRM is self explanatory, Y* is -10log(Y) and I'm displaying the data this way simply because SRM is -10log(transmission) though SRM is measured in an inch and Y in a cm. This is important as we shall see. x and y are the chrominance coordinates, Sat is the percent saturation of the color. 100% means a pure color. l_dom is the dominant wavelength (i.e. the hue) and Color is a description in words which covers a range of predominant wavelengths. Beer SRM Y* x y Sat l_dom Color 1 13.8 1.79 .426 .434 63% 577nm Yellow 2 14.5 1.91 .427 .437 63% 575 Yellow 3 4.3 0.63 .349 .365 22% 577 Yellow 4 42.9 7.15 .558 .427 95% 588 Orange 5 25.7 4.29 .496 .446 85% 582 Yel-Or 6 5.0 0.66 .354 .372 27% 576 Yellow -More- Return to table of contents
Date: Sun, 28 Jun 1998 19:36:57 -0400 From: AJ <ajdel at mindspring.com> Subject: Color II The first thing we see from these data is that the beers analyzed are, though they vary in color from the very pale wheat beer at 4.3 to the quite dark porter at 42.9 SRM all very close to the same color. The color spectrum from violet to red (400 to 700 nm dominant wavelength) encircles about 230 degrees on the chromaticity diagram. This set of beers in found in a wedge that is 9 degrees wide. Thus we are tempted to say "all beer is the same color it's just that some are darker than others" and simply measure the "darkness". This is the basis for the ASBC measurement. If we look at the Y* data for the beers analyzed and compare to the SRM values we find SRM = 2.43 + 5.68*Y* to a very good approximation (r = .997). I don't know for a fact but would venture a guess that the Subcommittee on Color in Beer took transmission data on lots of beers and did linear regressions of log luminance vs absorbance at several wavelengths. I'll further bet that 430 nm gave the best fit. This suspicion is confirmed by looking at the absorbtion spectra for beer. There is no peak at 430 nm so why use this particular wavelength?. Now of course there will be beers that fall outside this 9 degree wedge and those are, of course, the one's that George is talking about. A person with normal color vision can see the difference in color between beers even over the 9 degree range provided the color is reasonably saturated and, of course, saturation is ignored when the SRM method is used. Thus even with unusual cases aside the SRM method has its limitations. The bottom line here, assuming that the goodness of fit between log Y and SRM would be upheld with hundreds of beers instead of just 6 I've measured is: _specifying beer color with SRM and distinguishing beers based on this method is akin to distinguishing beer color as observed on a black-and white TV set_. Now that's OK. I used to watch black and white TV a lot when I was a kid. Luminance contains most of the information (the luminance signal in a color transmission is conveyed with lots more bandwidth that the chrominance, many lower animals have luminance perception only). Now one of the most interesting little discoveries of my investigations this afternoon is that perceived color (that's what x and y tell you about) depends on the depth of the beer being looked at. I took all data with a 1 cm cell but it's very easy to calculate what the transmission is at any other cell length. Here's some data on the New Castle Brown Ale for other path lengths: Path Y* x y Sat l_dom Color 1 cm 4.19 .496 .446 85% 582 Yel - Or 2 cm 7.63 .570 .420 100% 591 Orange 3 cm 10.63 .610 .388 100% 596 Orange 4 cm 13.32 .637 .362 100% 605 Or-Red The fascinating conclusion from this is that the wider the glass through which you look at NCBA is the redder it looks! My wife with normal color vision confirms this - with a little prompting. Note also that the log luminance does not increase at the same rate as the SRM metric. Thus if we did go to specification of beer color using the tristimulus model we'd have to specify the cell depth as well. This is in fact done when using this model for, for example, reporting the color of water samples. Summary: - Perceived beer color is communicated by 3 numbers (Note: a Taylor series expansion is perhaps more applicable than a Fourier series expasion as a means of describing the whole absorbtion spectrum but would require about a dozen terms). - The SRM measure agrees well (for our limited data set) with observed beer luminance in which sense looking at beer with SRM is like looking at it with a black and white TV - This is OK for most purposes since beers are all about the same hue (if not the same saturation). - The SRM method, like the tristimulus method is based on measurements and thus removes the potential for errors in judgement due to fatigue, accomodation, light quality etc. from the equation. There are still lots of ways to stuff it up, though. - Going along with George's comment about SRM being the first term in a series, I'll suggest that x and y are the second and third terms and that the series can be truncated at this point. Final Observation - I just sat the BJCP exam. I'd never do that again if I had to remember that Pils is about (0.66,0.354,0.372) instead of just good old 5 SRM! Return to table of contents
Date: Mon, 29 Jun 1998 05:15:13 -0700 From: Kyle Druey <druey at ibm.net> Subject: Dry Beer Al K describes his conundrum: >Three words: "alcohol is sweet." Yes, I've been trying to make a >dry IPA and I'm beginning to realise that the beer I've envisioned >may be an impossibility at the original gravity I'm trying to use. One possibility to dry out the beer is to increase the ion content of sulphate to maybe 200-300 ppm by adding some calcium sulphate to the boil (maybe 2 tsp per 5 gallons?). Sam Mize never drove the HBD welcome wagon to my in*box, what's the deal? Kyle Bakersfield, CA Return to table of contents
Date: Mon, 29 Jun 1998 05:31:27 -0700 From: Kyle Druey <druey at ibm.net> Subject: RIMS Does Not Require a Thin Mash Al K on RIMS and a thin mash: >you will need to have a *very* thin mash. Not as thin as you might think. The dead space in my RIMS tun is 0.75 gal, then I need another 0.25 gal of water that fills the RIMS piping. For 5 gal of a 50 gravity beer I need about 9 pounds of malt. I use a water to grist ratio of 0.9 qts/lb: total mash water = [(0.75 + 0.25)*4 + (9*0.9)] / 9 = 1.34 qts/lb I am no xpurt, but I don't think 1.34 qts/lb qualifies as a thin mash. >Remember that in addition to the liquid that you normally have in >the grain bed, you also have to have enough *additional* liquid to >fill your heat exchanger. Yes, see above. For my RIMS tun and piping this additional water is only 1 gallon. >Too thin a mash means your enzymes are very dilute, which in turn, >means that conversion will go slower and your enzymes will be more >easily denatured (this is just a fact of thin mashes). If you are mashing without circulating I think this is valid. But for RIMS, I don't think this applies. The enzymes are exposed much much of the grain surface area than with kettle mashing due to the constant circulation (some call this "recirculation"). Conversion is very rapid, less than 30 minutes in most cases. Kyle Bakersfield, CA Return to table of contents
Date: Sun, 28 Jun 1998 19:39:29 -0700 From: "Michael Kowalczyk" <mikekowal at megsinet.net> Subject: End of my career as a brewer? I'm thinkin Paul Niebergall is a pretty "Aware" guy. I'm tired too of the people pooh poohing techniques. I risk my career as a brewer by posting, because of this passion we all share and the amount of influence this forum brings...but come on! Al writes... Bill writes: >I use a glass on steel 5-gallon pot as mash tun for most of the beers I >brew. <snip> and: >Transferring the mash to the lauter tun only takes a couple of minutes and >allows the filter bed to set up better the in the single tun method. <snip> How so? I mash and laeuter in a single 18.75-gallon SS kettle into which is mounted three EasyMasher(tm)-like screens that are connected with a SS cross which is connected to a ball valve on the outside. I have never had any trouble establishing a filter bed (although I have not tried rye or wheat in this tun) and it has held as much as 46 pounds of malt. It has a 50,000 BTU ring burner under it. See my website for photos. Also, wouldn't the transfer of the mash from mashtun to laeutertun increase the amount of aeration of the mash that goes on? I have always tried to be very careful to minimise introduction of air during the mash, but I believe that Charlie Scandrett once posted that the introduction of air in the mash may be more detremental than post boil hot-side aeration. Isn't simpler better? ____ End of post. I've re-read this post 6 times, so I don't think I'm jumping the gun here. Al, Don't discount a technique simply because you don't beleive in it, or have not tried it. I've made 38 beers using a canning kettle as a mash tun and a phils phloating bottom. It requires me to mash and lauter in different vessels. I transfer the mash very carefully and it only takes me a few minutes (as Bill writes) to transfer. I usually mash-out a little higher because I know the transfer looses heat. Of the 38 beers I've made, I've had 3 of them after a year and more with what I would call (of course I'm not trained at Seibel) no bad taste. Nothing that I would call aeration of the mash. Of these beers I've never dumped one. Not even the one you helped me with (thanks Al..). I've stopped entering competitions after my 3rd batch (that one got me a "Very Good" on the score sheet). My technique changes constantly. I only brew to please me and my beer snob friends. The only real measurable feedback I have is that I can never keep a good cellar going because my friends alaways raid it.. I can live with that as a measure of how good my beer is. Please don't discount techniques. People have been brewing since the pyramids were built. I'm sure there are more than one or two techniques that have made outstanding beer in the years.... - Mike Kowalczyk Dirty Spammer Brewery Wrigleyville, Ill. p.s. After a 7th time re-reading this, it looks like Al took exception to "allows the filter bed to set up better the in the single tun method" of which I respond. " I kind of agree with Al that the single tun method would set up a pretty good bed in it's own right." Return to table of contents
Date: Sun, 28 Jun 1998 22:55:27 -0700 From: John_E_Schnupp at amat.com Subject: re: Citric beer >Has anyone ever tried to use lemon or other citrus fruit in the secondary >(particularly in wheat beer)? What was the result and how much did you add? Yeah, I tried. I used the zest and juice of two lemons in a recent 5 gallon batch of a blonde ale. It wasn't a wheat beer but it is a light colored and flavored beer. It was a beer which I have brewed many times in the past years. It's a great tasting summer swill beer. It was an extract brew. The lemon is very obvious both to the nose and the mouth. This beer is now about 2 months old and the lemon smell and flavor is becoming more smooth. I then brewed my first all grain batch of the same recipe. I did all the grain and hop calculations. I wanted to be able to compare the difference between the mash and extract versions. I did make one change in the extract version. I added the zest and juice of only 1 lemon to the secondary. I have not bottled it yet and won't get to do it until the end of July as previous commitments will keep me away from home. I got the zest by using a vegetable peeler. Just make sure you don't get the white pith just under the skin. I then cut the peeled lemons in half and squeezed them to get the juice. John Schnupp, N3CNL Colchester, VT 95 XLH 1200 Return to table of contents
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