HOMEBREW Digest #5504 Sun 15 February 2009


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


	FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
		Digest Janitor: pbabcock at hbd.org


***************************************************************
        TODAY'S HOME BREW DIGEST BROUGHT TO YOU BY: 

                 Sponsor The Home Brew Digest!
     Visit http://www.hbd.org/sponsorhbd.shtml to learn how
			 
    Support those who support you! Visit our sponsor's site!
********** Also visit http://hbd.org/hbdsponsors.html *********

DONATE to the Home Brew Digest. Home Brew Digest, Inc. is a 
501(c)3 not-for-profit organization under IRS rules (see the
FAQ at http://hbd.org for details of this status). Donations
can be made by check to Home Brew Digest mailed to:

HBD Server Fund
PO Box 871309
Canton Township, MI 48187-6309

or by paypal to address serverfund@hbd.org. DONATIONS of $250 
or more will be provided with receipts. SPONSORSHIPS of any 
amount are considered paid advertisement, and may be deductible
under IRS rules as a business expense. Please consult with your 
tax professional, then see http://hbd.org for available 
sponsorship opportunities.
***************************************************************


Contents:
  Re: Low Alcohol Big Beers ("Greg 'groggy' Lehey")
  HBD Server Fund (Fred L Johnson)
  O2 Saturation ("A.J deLange")
  FW: Yeast Performance / Aerobic propagation (Joshua Wilkins)
  re: Low Alcohol Big Beers (steve alexander)
  Re: aerobic growth is not respiration (Fred L Johnson)
  2009 Charles Town Homebrew Competition ("H. Dowda")

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * The HBD Logo Store is now open! * * http://www.hbd.org/store.html * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Beer is our obsession and we're late for therapy! * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * NOTE: With the economy as it is, the HBD is struggling to meet its meager operating expenses of approximately $3400 per year. If less than half of those currently directly subscribed to the HBD sent in a mere $5.00, the HBD would be able to easily meet its annual expenses, with room to spare for next year. Please consider it. As always, donors and donations are publicly acknowledged and accounted for on the HBD web page. THank you 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: Sat, 14 Feb 2009 17:07:55 +1100 From: "Greg 'groggy' Lehey" <grog at lemis.com> Subject: Re: Low Alcohol Big Beers On Friday, 13 February 2009 at 8:32:54 -0600, Eric (Rick) Theiner wrote: > Hail Brewmeisters, > > My preferred brews are big on flavor, body, hops, etc. > Thus I often brew IPA's and similar, but I would really > rather not have to deal with the typically accompanying > high level of ethanol. If I sit down for 3 or 4 over the > course of a few hours, I'd rather not be intoxicated at the > end of the evening. I know the feeling. > I have been thinking about playing around with high dextrine malts, > but before I started down that road, I thought I'd ask if anyone on > this list has done something along those lines... I've been trying this way for some time. The standard malts available here in Australia are relatively high in dextrins, but there's more to flavour than body. I'm brewing my current beers at about 13% Brix and then diluting 50:50 with water; the flavour is more hop-based than malt-based. I don't think I'll win any prizes for them, but they're comparable in body with full-strength commercial beers. Greg - -- Finger grog at Freebsd.org for PGP public key. See complete headers for address and phone numbers. Return to table of contents
Date: Sat, 14 Feb 2009 07:43:54 -0500 From: Fred L Johnson <FLJohnson52 at nc.rr.com> Subject: HBD Server Fund Hey, guys. Note in the header of the Homebrew Digest the appeal for us to financially support this great service. The janitors note that if we all gave a very small amount annually, the HBD can continue with financial ease. Otherwise, they deal with an endless struggle to keep the service running. Fred L Johnson Apex, North Carolina, USA Return to table of contents
Date: Sat, 14 Feb 2009 08:56:25 -0500 From: "A.J deLange" <ajdel at cox.net> Subject: O2 Saturation For Bill Kaiser: When you say "saturation" WRT O2 measurement that usually means WRT to air i.e. most DO meters will read 100% at about 8 mg/L at reasonably cool temperature. When oxygenating with pure O2, however, saturation means about 5 times this. When I used to oxygenate after the wort was in the fermenter (I now do it inline - as the wort enters the fermenter) I found it would take about 3 minutes to pin my meter which reads up to 20 mg/L (about twice air saturation and 2/5 pure O2 saturation) using a small(1 1/2 inch x 3/8 inch dia?) sintered stainless steel stone at a flow rate just sufficient to cause bubbles to appear at the surface. This I have always found to be sufficient. Obviously it's going to depend on the flow rate and the size of the bubbles somewhat. Be sure to move the stone around in the solution. As I recall the molecular sieves produce about 95% pure O2 so the results you get should be very similar to what you would get from bottled O2. A.J. Return to table of contents
Date: Sat, 14 Feb 2009 16:17:33 +0000 From: Joshua Wilkins <jowilki3 at hotmail.com> Subject: FW: Yeast Performance / Aerobic propagation Hey guys, I am very busy this weekend, so give me some time to respond back on Mon to some of the more specific things asked about my post.But I'll answer some now. "Do you have any ballpark recommendations on how long it would take to attain 100% saturation using a surplus medical O2 concentrator and an aquarium airstone? (that I just happen to have)" Yes, in my industry it is fairly standard to set the run parameters for at least 45- 60 minutes, although longer is better, before saturation is accomplished.We then calibrate DO probes to 100% saturation. Speaking of which since I know some of you have DO probes, be careful how you use them because they depend highly on how they are calibrated and maintained. Once calibrated to 100% saturation and zero % saturation, they need to remain within that media or else they need to be recalibrated to be accurate. Also the biggest problem with DO probes is that the probe itself needs to be replaced frequently when used in anything other than water. The media fouls up the membranes giving rise to inaccurate readings. In my industry we replace them every third batch, but I have seen in labs using them longer. But consult your literature on your specific models. Fred I cannot speak for white labs nor wyeast as I am not affiliated nor have I seen their facilities. But they are confined within another specific industry with particular goals (high biomass, sterility, cost, and shipping methods are probably their biggest issues), so using their methods for brewing should not be done. But knowing why they do things can help you in brewing. I would assume they are using aerobic growth for the high biomass yields. But I'll touch more specifically on your questions on Mon in a separate posting so I can get into some details. Matt you are correct that there is a lot of science terminology that gets used slightly incorrectly as shorthand in industry,so I apologize for the confusion. But I do have one correction to your statement, respiration more specifically speaks of the glycolytic pathway which is present in both aerobic and anaerobic growth phases (including alcoholic fermentation). In alcoholic fermentation respiration begins with glucose and ends with pyruvate before it gets shuttled into the actual alcoholic formation or diacytyl pathway. Also there is a lot of referencing to the Crabtree effect, of which I am also going to save for my post on Mon because I always confuse it with the pasteur effect and catabolic repression when going from memory, so I want to go back to their definitions, but from memory it does not play as critical a role as you all make it sound. These three are very important effects to know of for troubleshooting,but they are not as common as you may think. They DO NOT define or govern a fermentation process, but they do occur in it. Happy Valentines Day.. Josh Wilkins Return to table of contents
Date: Sat, 14 Feb 2009 13:58:24 -0500 From: steve alexander <steve-alexander at roadrunner.com> Subject: re: Low Alcohol Big Beers Rick Theiner mentions, > My preferred brews are big on flavor, body, hops, etc. > Thus I often brew IPA's and similar, but I would really > rather not have to deal with the typically accompanying > high level of ethanol. If I sit down for 3 or 4 over the > course of a few hours, I'd rather not be intoxicated at the > end of the evening. > > I have been thinking about playing around with high dextrine > malts, but before I started down that road, I thought I'd ask > if anyone on this list has done something along those lines... > > And if not, what are your general thoughts on getting to my > goal of a really big, but low alcohol beer? > > Rick Theiner > Rick - our preferences have a lot of overlap. I really like flavorful interesting beers, but for everyday drinking the 15P+ monster beers aren't a good choice. OTOH alcohol definitely has an impact on body/ mouthfeel. Perhaps I'm wrong, but my feeling is that (using conventional methods) it's not possible to create a really big low-alc beer. Flavors like big hops must be balanced with big malt. To include so much malt flavor means high OG and your only choice is to either attenuate the OG into big alc or leave the OG as big dextrin; neither is acceptable in a session beer IMO. In my experience if you start around 12P,with attenuation much below 72%AA by either mashing or loading up on crystal, then you end up with one of those syrup-y dextrinous beers [gluhbier] that isn't useful as a session beer. You can make a very good APA/IPA style beer (perhaps violating the style guidelines) starting at an OG of 12P, but don't expect to include 75IBU. You'll want to make extravagant use of specialty malt, but again - the attenuation needs to be reasonably high. You can push the malt flavors upward by a careful choice of malt .. a good toasty UKpale malt, or melanoidin or munich malt perhaps, some wheat then match malt flavors w/ hops. Still, you have a fundamental limitation; you can only hop to match the malt flavor, the malt flavor is limited by the OG, and the OG results in either alcohol or dextrin - checkmate ! It's no wonder that many traditional session beers start like at 7.5-10P, since w/ modest alc and modest dextrin you can drink many of these and they still taste good. -S Return to table of contents
Date: Sat, 14 Feb 2009 14:06:35 -0500 From: Fred L Johnson <FLJohnson52 at nc.rr.com> Subject: Re: aerobic growth is not respiration Matt points out that we should simply refer to respiration versus fermentation in the discussion of yeast propagation, with respiration being aerobic whereas fermentation can be aerobic or anaerobic. I would probably generally agree with this except that many folks use the phrase "anaerobic respiration" as being equivalent to "fermentation". To avoid confusion, I will try to use the phrase "aerobic respiration" to clearly distinguish purely oxidative production of carbon dioxide and water from the process that yields carbon dioxide and ethanol. To reiterate, the production of ethanol is the hallmark of fermentation. The goal of yeast propagation with very low concentrations of sugars in the medium in the presence of oxygen is to convert as much of the energy contained within those sugars into cell mass rather than to lose it in the mass of ethanol. Fred L Johnson Apex, North Carolina, USA Return to table of contents
Date: Sat, 14 Feb 2009 19:49:06 -0800 (PST) From: "H. Dowda" <hdowda at yahoo.com> Subject: 2009 Charles Town Homebrew Competition Entries for the first AHA sanctioned Charles Town Homebrew Competition are being taken. Entries and paperwork must be in Charleston S.C by Feb 28. BJCP judges are especially invited. Enter and help us get homebrewing competitions going strong in the S.C. Lowcountry. Visit: www.lowcountrylibations.com for complete info Return to table of contents
[Prev HBD] [Index] [Next HBD] [Back]
HTML-ized on 02/15/09, by HBD2HTML v1.2 by KFL
webmaster@hbd.org, KFL, 10/9/96