HOMEBREW Digest #250 Mon 11 September 1989

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

		Rob Gardner, Digest Coordinator

  Homebrew Digest #249 (September 10, 1989)
  doubts about SG temp corrections (Dick Dunn)
  "How not to open a beer" (Alex M. Stein)

Send submissions to homebrew%hpfcmr at hplabs.hp.com Send requests to homebrew-request%hpfcmr at hplabs.hp.com
---------------------------------------------------------------------- Date: Sun, 10 Sep 89 03:06 CDT From: postmaster at ihc.att.com Mail to `estes' alias `local!estes' from `arpa!hplabs.hp.com!homebrew%hpfcmr' failed. The error message was: corrupted mailbox. The message was: Received: from hpfcla.hp.com by hp-sde.sde.hp.com with SMTP (15.7/SES42.42) id AA16059; Sun, 10 Sep 89 00:53:04 pdt Received: from hpfcmr.HP.COM by hpfcla.HP.COM; Sun, 10 Sep 89 01:02:26 mdt Received: by hpfcmr.HP.COM; Sun, 10 Sep 89 01:00:01 mdt Date: Sun, 10 Sep 89 01:00:01 mdt Full-Name: Rob Gardner Message-Id: <8909100700.AA11386 at hpfcmr.HP.COM> From: homebrew-request@ hpfcmr.hp.com (Are you SURE you want to send it HERE?) Reply-To: homebrew%hpfcmr at hplabs.hp.com (CHANGE THIS IF NECESSARY) Errors-To: homebrew-request%hpfcmr at hplabs.hp.com Subject: Homebrew Digest #249 (September 10, 1989) Apparently-To: realhomebrew at hpfcmr.hp.com HOMEBREW Digest #249 Sun 10 September 1989 FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES Rob Gardner, Digest Coordinator Contents: doubts about SG temp corrections (Dick Dunn) Send submissions to homebrew%hpfcmr at hplabs.hp.com Send requests to homebrew-request%hpfcmr at hplabs.hp.com Return to table of contents
Date: 9 Sep 89 01:04:58 MDT (Sat) From: hplabs!gatech!raven!rcd (Dick Dunn) Subject: doubts about SG temp corrections I've been watching the discussion of temperature corrections for hydrometer readings for a while. I guess it's time to toss in my twopence. A quick check in the Rubber Bible seems to indicate that the temperature coefficient of expansion of water over some interesting range (say 50-100 F), while not linear, is not warped enough to give you as much as a point of error relative to a 60 F reference. So that's cool...however: - How does the expansion change with sugar in the water? There are two questions here. First, how much does the coefficient change--that is, do you have to apply a significantly different temperature correction factor depending on the gravity? Second, does it get more or less linear than the expansion of water? - What about the expansion of the glass in the hydrometer itself? Is this really negligible? I've always gone by the (safe, but perhaps overly conservative) rule that you shouldn't try apply temperature corrections outside the range of per- haps 50-75 F. This seems like a good idea given the potential for non- linearity in expansion coefficients, difficulty in getting temperature measurements right, tendency to warm/cool while you take the measurement, etc. One other note-in-passing: Somewhere there was a discussion of the "poten- tial alcohol" scales on hydrometers. I have two hydrometers. Both show potential alcohol, and both clearly say "by volume", but they're not the same. However, the one that's different (:-) has the zero for potential alcohol at a gravity value other than 1.000. Is this just a simple screwup, or does someone know a reason this might make some sense? Seems wrong to me...I'd expect water to have SG of 1 and potential alcohol of 0. --- Dick Dunn {ncar;ico;stcvax}!raven!rcd (303)494-0965 or rcd at raven.uucp Return to table of contents
End of HOMEBREW Digest #249, 09/10/89 ************************************* ------- Return to table of contents
Date: Wed, 6 Sep 89 14:18:01 PDT From: rutgers!retix.retix.com!alexs at hplabs.HP.COM (Alex M. Stein) Subject: "How not to open a beer" Reprinted from Chemical & Engineering News: "A weird encounter with a non-screw-on beer-bottle cap was reported recently by physician Karanvir Prakash and colleagues at Bronx-Lebanon Hospital Center, Bronx, N.Y. "The subject, a man aged 36, was `watching a tense baseball game on a hot summer afternoon.' He was opening a bottle of beer with his teeth when the compressed gas inside blew the loosened cap down his throat. Off to the emergency room. The cap had to be removed surgically because its serrations were `firmly embedded' in mucous membrane. The physicians' report of the episode describes the cap carefully as `measuring 2.7 cm in diameter and bearing the words MILLER HIGH LIFE.' The patient came out okay. "The episode `highlights the hazard of opening bottles of carbonated drinks with the teeth,` say Prakash, et al. They suggest that such drinks be marketed only in cans. You could cut your fingers, but that would appear to be preferable to a bottle cap in the throat." Alex Stein alexs at retix.com Return to table of contents
Date: Sun, 10 Sep 89 21:07:46 PDT From: CASEY%MIT.MFENET at CCC.NMFECC.GOV Subject: CASEY at MIT.MFENET subject: amateur yeast experiment: I started brewing only four months ago, and am still in the wild experimentation stage. I quickly became confused about different brands of yeast available, and was able to get almost no reliable information, so I tried an experiment. The results are posted below. I just joined this bboard, so I have no idea if this sort of thing is common. I'd love to hear of other experience or comments along the same line. If this is an old subject, just flame to me directly instead of clogging up the board. First: I already realize that I used a pretty bad recipe for the test. It had far too much bittering hops for balance. The idea was to look for differences in yeasts, however, so I tried to look through it. I was also experimenting on yeasts suitable for my conditions (Boston in summertime), where the temperatures are ungodly hot, and mold runs rampant. I also realize the problem with my lack of gravity measurements and exact temperatures, sorry. Don't chew me out for these, but I would be interested to hear if one of the "bad" yeasts might be perfectly good under other circumstances. 7 gallon recipe: 2x 3.3# can M&F light unhopped .75# M&F light unhopped spray .75# crystal (steeped while coming to boil) 1 tsp gypsum 2oz clusters boiling .5 oz cascades finishing Divided evenly into seven 1 gal bottles, different yeast in each bottle. Fermented at about 75-85 F. Results were: 1st: Edme ale - best overall. rounded, slightly sweet. some diacetyl. nice balance. fermented rather slowly (3-4 days). 2nd/3rd: Whitbread ale - lighter, crisp. poorer head. some esters. very fast fermentation. 2nd/3rd: CWE ale - slight yeasty bite. very dry (attenuative). good head. no esters. extremely fast fermentation (frighteningly). ... these three were all quite good, and I have been using them successfully since then. they all rated fairly close together. the remaining four were all quite a bit worse (a very big gap in quality), and I haven't touched them since. none seemed to have spoiled, they just had unforgiveable ester content and/or carbonation qualities. (this could be due to temperature). 4th: M&F ale - heavy yeast bite. flat head. very little ester taste. 5th: Kitzengen lager - (fermented warm) this had the best head and carbonation quality. very dry (attenuative). extremely bad ester content. 6th: Doric ale - yeast bite. very estery. bad head. overall horrible. 7th: Red Star ale - same as Doric, but a little worse. these were the results of two different double blind tests, with only minor variations between the two events. I might try this sort of thing again with a better recipe after it cools down, and include some liquid cultures that I've tried since (with luck); unless somebody else out there has done it for me and can post the results. I have heard that the next issue of Zymurgy will cover yeasts - perhaps all this will be superceeded soon. Jeff Casey CASEY%MIT.MFENET at CCC.NMFECC.GOV Return to table of contents
End of HOMEBREW Digest #250, 09/11/89 ************************************* -------
[Prev HBD] [Index] [Next HBD] [Back]
HTML-ized on 06/29/00, by HBD2HTML version 1.2 by K.F.L.
webmaster at hbd.org, KFL, 10/9/96