HOMEBREW Digest #5182 Thu 03 May 2007

[Prev HBD] [Index] [Next HBD] [Back]

		Digest Janitor: pbabcock at hbd.org


                     Your Business Name Here
    Visit http://hbd.org "Sponsor the HBD"  to find out how!
    Support those who support you! Visit our sponsor's site!
********** Also visit http://hbd.org/hbdsponsors.html *********

  malt (leavitdg)
  Re: keg priming vs. oxidation (Jeff Renner)
  Beer-Lambert (mabrooks)
  Re:  Immersion chiller vs. kettle temperature probe ("Craig S. Cottingham")
  Peristaltic pump ("Doug Moyer")
  Quebec Beer (Rick) Theiner" <rickdude@tds.net>

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * The HBD Logo Store is now open! * * http://www.hbd.org/store.html * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Suppport this service: http://hbd.org/donate.shtml * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Beer is our obsession and we're late for therapy! * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Send articles for __publication_only__ to post@hbd.org If your e-mail account is being deleted, please unsubscribe first!! To SUBSCRIBE or UNSUBSCRIBE send an e-mail message with the word "subscribe" or "unsubscribe" to request@hbd.org FROM THE E-MAIL ACCOUNT YOU WISH TO HAVE SUBSCRIBED OR UNSUBSCRIBED!!!** IF YOU HAVE SPAM-PROOFED your e-mail address, you cannot subscribe to the digest as we cannot reach you. We will not correct your address for the automation - that's your job. HAVING TROUBLE posting, subscribing or unsusubscribing? See the HBD FAQ at http://hbd.org. LOOKING TO BUY OR SELL USED EQUIPMENT? Please do not post about it here. Go instead to http://homebrewfleamarket.com and post a free ad there. The HBD is a copyrighted document. The compilation is copyright HBD.ORG. Individual postings are copyright by their authors. ASK before reproducing and you'll rarely have trouble. Digest content cannot be reproduced by any means for sale or profit. More information is available by sending the word "info" to req@hbd.org or read the HBD FAQ at http://hbd.org. JANITORs on duty: Pat Babcock (pbabcock at hbd dot org), Jason Henning, and Spencer Thomas
---------------------------------------------------------------------- Date: Thu, 03 May 2007 05:43:41 -0400 From: leavitdg at plattsburgh.edu Subject: malt Malt is a barley that disdains fame. (Darrell Gibran) Return to table of contents
Date: Thu, 3 May 2007 09:12:05 -0400 From: Jeff Renner <jsrenner at umich.edu> Subject: Re: keg priming vs. oxidation Brian Miller <bj_mill at pacbell.net> wrote: > the bottle conditioned beer was > pretty easily detected from the kegged one, and the bottled version > was much 'better'. I've about run out of ideas besides keg priming to > avoid this problem in the future. Is this common knowledge or am I > missing something? Nice to have a datum point, if only a single one, for this. I have long believed that bottles filled from kegs suffered, but hadn't thought about this possibility. Food for thought. And I have a few thoughts. A few years ago here we discussed the purity of commercial CO2. It seems that there is a small amount of O2 in it - well under a percent as I recall. This discussion was prompted by a campaign of A/H to provide extra pure CO2 for its draft accounts. This is from hazy memory - perhaps others can recall more details. Perhaps I should check with my CO2 supplier to see how much O2 there is in it. How long was your beer in the keg, how much had you dispensed before testing (thereby potentially introducing more O2), and did you force carbonate it (I assume so)? My preferred method of kegging and carbonating beers (ales and lagers) is to wait until they are almost done fermenting, and then to rack them from the primary to the keg and let them finish up there. I don't bother to completely purge the keg when doing this the way I do when transferring finished beer, but I do avoid splashing by running the beer in the "beer-out" fitting so it is delivered to the bottom of the keg via the dispensing tube. When I do it right, I get proper carbonation (though I sometimes adjust carbonation by venting or adding CO2), and the yeast should handle any introduced O2. This is called bunging, or spunding, traditional in England for real ale (often some priming sugar is added) and with some German beers, especially Kellerbier. See http:// www.trailmonkey.com/lounging/yeasty.htm#Spunding I only rack them to another keg to transport them or to rack them to a smaller keg (Sankey to Corney) to save space. But, I certainly do dispense with ordinary CO2. As has often been noted, yeast is our friend. Jeff - --- Jeff Renner in Ann Arbor, Michigan USA, jsrenner at umich.edu "One never knows, do one?" Fats Waller, American Musician, 1904-1943 Return to table of contents
Date: Thu, 3 May 2007 07:49:16 -0700 (PDT) From: mabrooks <mabrooks12 at yahoo.com> Subject: Beer-Lambert Recent postings on the subject topic have stated that Beer does in fact follow Beers law....hmmmm, perhaps it does, however, I would like to throw out the following to ponder: Diluting a liquid by 10, 20 or 50% and meauring it on a spectrophotometer, by no means proves it follows Beer-Lambert(doesnt disprove it either). Simple Dilution-Law could account for the reduction one is seeing when performing this type of "highly scientific experiment" If you dont have a known initial concentration to verify that the concentration actually was reduced by 10, 20 or 50% of its original concentration of then how do you prove Beer-Lambert? Beer-Lambert Law definately uses "concentration" and if you did not measure it before you started your dilutions then what you did was "assumed a starting "level" of something, no "knowns" whatsoever. If "c" is unknown at the begining and unknown at the end of the experiment then how do you prove Beer-Lambert? "c" MUST be measured and expressed in a unit per volume or weight, typically for water it is mg/L. Just because the Absorbance dropped with dilution does not prove the concentration did as well? You HAVE TO MEASURE the "c" at the begining and end of the experiment. If you do not, and you only measure the absorbance? then you are "hypothesizing" that the concentration was actually changing! This wont fly in the world of Acedemia! While perhaps some constituant of Malt/Beer may in fact weakly follow Beer-Lambert, it cannot be associated with the "aparent color" of the beer as seen with the naked eye. This is not possible as there are no absorbance peaks in any of the spectrum from 400-700nm.....None ! No peaks means no dominant color absorbance...that is just plain simple spectrophotometry. If you dont know what "constituant" in the sample you are measuring the absorbance of, and you believe is following beers law, what is the point of the research? You can take just about any liquid and run it on a spec, dilute it and run it again and say it follows Beer-Lambert law? What is the point...It is not associated with the aparent color of the beer! Thats the point I am trying to make! Pick up a copy of standard methods for the examination of water & wastewater(this is the definitive book for approved laboratory analysis on water samples)and look up how they determine color of a liquid...you will find that it is very similar to what the Brewing industry is finally moving toward. The issue is not one of Beer-Lambert, rather the realistic acknowledgement that the Beer-Lambert law doesnt apply to measuring Color of a liquid.....it does not say liquids dont follow the Beer-Lambert law, it is just that it is not readily apparent nor easy to determine what constituant in a liquid is causing it to follow the Beer-Lambert Law, Hence it does not apply to color measurement. In the same book you will see countless applications of approved methodologies for analysis of water samples by applying the Beer-Lambert Law, none have to do with aparent color of the sample, rather they deal with determining actual concentrations of a particular consituant of interest. The results are always displayed in mass per volume or mass per unit weight. This is the guiding principal for the use of Beer-Lambert law for analysis of liquids, the concentration of a particular constiuant is the goal. You have to know what you are looking for, and know what wavelength it adsorbs the most light. Again, If you dilute something by 10, 20, or 50% and get linear readings on a spec, it doesnt necessarily mean it follows Beer-Lambert Law as far as aparent color is concerned? If you dont know the initial concentration of the absorptive constituant to begin with then you certainly dont know it after you dilute it, so how can you necessarily prove that a solution follows Beer-Lambert Law. You can safely assume that the dilutions caused a proportional drop in the absorbance of a liquid...that is not Beer-Lambert Law though? That is the Dilution Law.... Matt B. Northern VA Return to table of contents
Date: Thu, 3 May 2007 09:33:04 -0500 From: "Craig S. Cottingham" <craig.cottingham at gmail.com> Subject: Re: Immersion chiller vs. kettle temperature probe On May 1, 2007, at 23:54, nathanw at MIT.EDU (Nathan J. Williams) wrote: > Other thoughts? I'm leaning towards 3, bending the chiller - it's > standard home-improvement-store refrigeration copper tubing, fairly > narrow, and I bent it into this coil so I'm pretty sure it can deform > a bit more. You have a fifth option that I can think of. There's no harm in leaving the immersion chiller in your kettle for the entire boil, so you could assemble the chiller and thermometer before adding wort, and disassemble it for cleaning after the boil. Okay, I say "no harm", but it occurs to me that there is at least one potential hazard. An immersion chiller is a heat exchanger, and it works both ways. By the time you turn on the cooling water, that copper coil will be at 100 degC (adjusted for atmospheric pressure), so the first water that enters it will boil more or less instantly. As long as the outflow end of the chiller has a hose attached to it, it shouldn't be a problem, but it's something that you should be aware of. - -- Craig S. Cottingham BJCP Certified judge from Olathe, KS ([621, 251.1deg] Apparent Rennerian) craig.cottingham at gmail.com Return to table of contents
Date: Thu, 3 May 2007 14:09:56 -0400 From: "Doug Moyer" <shyzaboy at yahoo.com> Subject: Peristaltic pump I purchased a peristaltic pump off of eBay. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280101950611 I have no documentation to go with it, and I've never used a peristaltic pump before. For those of you that use these things, please answer a question or two... I would like to use this to transfer beer between fermenters (or from fermenter to keg) so I don't have to lift the carboys (if I can avoid it) due to back problems. Does it require priming or is it self-priming? What type of hose should I use? Any suggestions for care and feeding of this beast? Brew on! Doug Moyer Troutville, VA Star City Brewers Guild: http://www.starcitybrewers.org Beer, brewing, travel & kids: http://shyzaboy.blogsome.com Return to table of contents
Date: Thu, 3 May 2007 15:10:54 -0500 From: "Eric (Rick) Theiner" <rickdude at tds.net> Subject: Quebec Beer Hail Collective, I'm going to be in Quebec (city), Quebec in a couple of weeks. Where's a good place for a few beers? I'll be staying close to the conference center in the Leow's Hotel, if that helps. Thanks! Rick Theiner Return to table of contents
[Prev HBD] [Index] [Next HBD] [Back]
HTML-ized on 05/04/07, by HBD2HTML v1.2 by KFL
webmaster@hbd.org, KFL, 10/9/96