HOMEBREW Digest #5776 Wed 19 January 2011

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

		Digest Janitor: pbabcock at hbd.org


                 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.

  Over-Carbonation? Fermentation Re-Start Question ("John W. Zeller")
  Bulging kegs? ("Spencer W. Thomas")
  Re: Over-Carbonation? Fermentation Re-Start? (Calvin Perilloux)

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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 $3500 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. Financial Projection As of 19 Jan 2011 Projected 2011 Budget $3271.04 Expended against projection $ 520.75 Projected Excess/(Shortfall) ($2226.61) 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, Spencer Thomas, and Bill Pierce
---------------------------------------------------------------------- Date: Tue, 18 Jan 2011 23:59:39 -0500 From: "John W. Zeller" <jwzell at cincic.com> Subject: Over-Carbonation? Fermentation Re-Start Question Trish requested opinions on why her mini-kegs are bulging from excessive carbonation when only a minimal amount of priming sugar was used. My guess would be that there was a substantial amount of residual CO2 in the beer when it was kegged. The Octoberfest mentioned is a lager, so it would typically be fermented at about 50F usually fallowed by an extended lagering period at much colder temperatures. A diacetyl rest at near room temperature for 4-6 days should allow most of the residual CO2 to dissipate, but if the diacetyl rest was skipped and there were some residual sugars remaining in the beer going int lagering, then much the CO2 could still be in the beer when it was kegged. The CO2 generated by the yeast while consuming the priming sugar plus the residual CO2 could be enough to bulge the kegs. The excess CO2 had to come from somewhere and I can only conclude that much of it was already in the beer when it was kegged as you indicated that the fermentation had finished out normally. Give us more detail on your temps during fermentation, diacetyl rest and lagering period and we might be able to spot something. Also, what was your F.G.? If it was unusually high it could be an indication that the fermentation had not finished out completely. john zeller cincinnati Return to table of contents
Date: Wed, 19 Jan 2011 10:54:32 -0500 From: "Spencer W. Thomas" <hbd at spencerwthomas.com> Subject: Bulging kegs? My guess is that, indeed, fermentation had not finished when you kegged. I don't believe that residual CO2 would provide enough pressure to bulge your kegs. How can you test for complete fermentation? The simplest test is a "forced fermentation" test. Fill a beer bottle about 3/4 with your pitched wort, fit an airlock (or just cover the top with foil), and place it in a warm location (80F-ish), such as above the refrigerator. Within a few days, your wort should ferment to completion. It might not taste very good, but that's not the point. Degas it, and measure the specific gravity. Compare to the beer in your fermenter. If it's more than 0.002 different, you're not done fermenting. If it's over 0.004 different, you risk "bottle bombs" or bulging kegs. 0.004 SG is 1 degree Balling, or 1% by weight sugar, thus 10 grams of sugar per liter. 10 grams of sugar produces about 5 grams of CO2 when fermented. 5 grams of CO2 is about 2.5 liters at room temperature and atmospheric pressure. Compressing that 2.5 liters into the 1 liter of beer gives you 2.5 "volumes" of extra carbonation. I used the carbonation calculator at hbd.org (http://hbd.org/cgi-bin/recipator/recipator/carbonation.html) to find the pressure that 2.5 "volumes" of CO2 produces at various temperatures: 35F - 10PSI 45F - 15PSI 55F - 20PSI 60F - 23PSI 65F - 26PSI 70F - 29PSI If you've already carbonated your beer to 2.5 "volumes", then the additional 2.5 "volumes" will give these pressures: 35F - 34PSI 45F - 44PSI 55F - 53PSI 60F - 58PSI 65F - 63PSI 70F - 69PSI You're getting into bulging and bottle bomb range there. =Spencer in Ann Arbor Return to table of contents
Date: Wed, 19 Jan 2011 12:46:16 -0800 (PST) From: Calvin Perilloux <calvinperilloux at yahoo.com> Subject: Re: Over-Carbonation? Fermentation Re-Start? Trish, I'm curious, what kind of kegs are you using where you have bulging kegs and raised bungs? That's really not good at all with any of the kegs I've dealt with. Have you checked the actual pressure using a gauge? Might even be dangerous. In any case, a key detail is in your statement: >> the bungs were raised on every keg for the batch we made >> AFTER that (Belgian Honey Ale, pitched and kegged in December) This would indicate to me, assuming you are consistent with your priming sugar additions before and after, that you have a wild yeast infection in your bottling/kegging equipment. Yes, it is possible that the yeast stalled for a while just as you kegged it, but seems unlikely with multiple batches, and I assume this FG was similar to the other O'Fests's FG. Some wild yeasts can eat up a lot more sugars and dextrins in the beer than normal ale or lager yeast does, and it is common for homebrewers with problematic batches to have lots of carbonation problems and gushing. Interestingly (though logically), the beer is often crystal clear. You will often, though, find phenolic notes in the beer, sometimes strong and sometimes less so; this is because wild yeast generally will not have the same "clean" character as typical brewing yeast. To remedy some of the carbonation problem in existing beer: (1) Can you release pressure on the keg for now? I have no idea what you mean about releasing the bottom seal on the keg (bottom seal washer on a Sanke outlet?), but what you might do is hook up a tap and pull off several pints, as well as release most of the top pressure via the tap's pressure relief. Then remove the tap -- I'm assuming a Sanke -- and the keg is less pressurized and still has no air in there. Do this a few times over a week, and you can reduce the interior pressure just a bit. (2) Put those kegs in the cooler at 32 F now! If you have wild yeast in there, chilling them to near freezing will at least reduce further carbonation activity. Alternatively, you might consider adding sorbate or a similar preservative to the beer, though most people balk at that solution. For future brews: (1) Should you even use priming sugar? If it were me, and it were beer for a festival and needed to be transported, I'd say no, not unless there was a reason you want the beer to be on the yeast (e.g. Real Ale). Forced carbonation is more controllable and leaves less sediment. (2) - Is priming sugar the likely cause for the pressure? No, see my above explanations. You probably need to strip down whatever equipment you are using and sanitize it thoroughly. I'd replace most or all plastic parts. What sanitizer are you using? (Just use a good one.) Heat treat things that you can't get into easily. Calvin Perilloux Middletown, Maryland, USA Return to table of contents
[Prev HBD] [Index] [Next HBD] [Back]
HTML-ized on 01/20/11, by HBD2HTML v1.2 by KFL
webmaster@hbd.org, KFL, 10/9/96