Homebrew Digest Thursday, 25 July 1996 Number 2124

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


   FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
        Shawn Steele, Digest Janitor
        Thanks to Rob Gardner for making the digest happen!

Contents:
  Re: Seibolt (sic) Institute ("Robert Marshall")
  Gelatine (Rob Moline)
  brew skool,corn,wheat ((Dutch))
  RE: Fruit Beers ("Frederick L. Pauly")
  Re: What's Aeration (KennyEddy at aol.com)
  Wooden Beer Barrels ((Jim Overstreet))
  RE: HSA when decocting, Blue whale ale, Hop pellets ((George De Piro))
  Re: Indoor Propane (RUSt1d?)
  Cream Stout?? (Schwab_Bryan at CCMAIL.ncsc.navy.mil)
  Fruit Flavorings (Fred Hardy)
  Re: Blue Whale Ale (RUSt1d?)
  Propane (Scott Dornseif)
  Aeration. (Russell Mast)
  Condensation Problems? (Michael Caprara)
  Mash tun and extraction testing (Alan)
  Fruit Fresh Falsehood ((Jim Layton 952-3733))
  blue whale bitterness (M257876 at sl1001.mdc.com (bayerospace at mac))
  Aeration / a fishy story ("Dave Hinkle")
  Wheeler's Porter article (korz at pubs.ih.lucent.com)
  Aeration; Consumption; Propane; Hazelnut (Bob Waterfall)

For SUBMISSIONS to be published, send mail to: homebrew at aob.org For (UN)SUBSCRIBE requests, send mail to: homebrew-digest-request@ aob.org and include only subscribe or unsubscribe in the body of the message. Please note that if subscribed via BEER-L, you must unsubscribe by sending a one line e-mail to listserv at ua1vm.ua.edu that says: UNSUB BEER-L If your address is changing, please unsubscribe from the old address and then subscribe from the new address. If your account is being deleted, please be courteous and unsubscribe first. For technical problems send e-mail to the Digest Janitor, shawn at aob.org. OTHER HOMEBREW INFORMATION http://www.aob.org/aob - The AHA's web site. http://alpha.rollanet.org - "The Brewery" and the Cat's Meow Archives. info at aob.org - automated e-mail homebrewing information. ARCHIVES: At ftp.stanford.edu in /pub/clubs/homebrew/beer via anonymous ftp. Also http://alpha.rollanet.org on the web and at majordomo at aob.org by e-mail.
---------------------------------------------------------------------- From: "Robert Marshall" <robertjm at hooked.net> Date: Tue, 23 Jul 1996 19:20:46 +0000 Subject: Re: Seibolt (sic) Institute Jim asked: >In other questions - does anyone have the scoop on a place here >in Chicago called the Seibolt Institute (sp?).. Could you possibly be referring to the Siebel Institute?? If so, I found out yeasterday, that they have a WWW page at: http://www.siebel-institute.com/welcome Hope that helps. Later, Robert Marshall robertjm at hooked.net homepage: http://www.hooked.net/users/robertjm - ---------------------------------------------- "In Belgium, the magistrate has the dignity of a prince, but by Bacchus, it is true that the brewer is king." Emile Verhaeren (1855-1916) Flemish writer - ------------------------------------------------ Return to table of contents
From: Rob Moline <brewer at kansas.net> Date: Wed, 24 Jul 1996 23:05:46 -0500 Subject: Gelatine Jethro's Gelatine- OK, one more piece of evidence that Jethro doesn't know .... Gelatine.....Andy taught me..(previous HB)..to stir gelatine into cold H2O for fining...and the beers were clear...after 4 months....(only during closed time, waiting for re-opening, at least sanitation was good)..but after getting on to Dry_fine...(Isinglass)...I still use gelatine in cold Isinglass prep, using gelatine added at the last...and just blended into cold I-glass prep....then added to initial beer flow into secondary.... The beers are clear...to the point that one respondent to the BEER SURVEY CARD, said that "the bartender was mistaken, 'cos the wheat was clear!! Maybe he didn't know what he was pouring!!" (30 % wheat malt)... To me, Isinglass is the key, but I have used gelatine cold for 2 years and I won't stop, nor will I heat it... Jethro Cheers! Rob Moline Little Apple Brewing Company Manhattan, Kansas "The more I know about beer, the more I realize I need to know more about beer!" Return to table of contents
From: leake.5 at osu.edu (Dutch) Date: Thu, 25 Jul 1996 02:36:52 -0400 (EDT) Subject: brew skool,corn,wheat yes, yes, yes, I'm finally caught up. went on vacation for two weeks in June and just got caught up. Brew skool - I work for a guy that went to the brew skool in Chicago (short session) and apprenticed at the goose island. He said he would of learned more about (practical) brewing and running a brewery if he had spent his whole time in a brewery. He felt the skool was more for someone who wanted to brew for one of the big boys. He is now the brew master (brewer) for 4 or 5 micros. corn - I want to brew using corn. The corn i want to use i may only be able to get as flower or whole kernel. Which would be better to brew with if I can't get grits or flaked corn? It is very likely i will not be able to get these because of the variety of corn i want to use. I want to use 1.5 - 2 # corn, 8# 2-row, 0.5 - 1# 20 L crystal (maybe the new 2 L German crystal my local store just got in) Would 1056 American work OK with this? wheat - I have read (maybe brewing lager beers) that it is best to grind wheat fine so the enzymes in the mash can easily get to the starch. I recently talked with someone who though finely milled wheat caused slow or stuck sparge so he had his wheat milled so that each kernel was broken into approximately five pieces. This seems to me to be more likely to cause a difficult sparge. Any thoughts? (this whole paragraph is about malted wheat) OH Gelatin - This may not be popular but why use animal products in your beer when most often they are not necessary. (most gelatin is derived from animal sources although some vegetable gelatin is available.) I know that swim bladders and gelatin have traditionally been used in some beer but do we as home brewers need them. Many things that make beer cloudy also make it taste (feel) good and not all beers need to be completely bright IMHO. (I do consume met but not every day like beer) Private e-mail is great I don't want to start another grind and mill thread. If these questions are repeats sorry. walter leake.5 at osu.edu Return to table of contents
From: "Frederick L. Pauly" <flp2m at galen.med.virginia.edu> Date: Thu, 25 Jul 1996 08:18:34 -0400 Subject: RE: Fruit Beers I've tried making a few fruit beers, using fresh fruit in primary or secondary fermenters. In both cases the beers had some slight aroma and a little tase of the fruit but there was always a drying finish (tannin ?). Recently I visted the Potomac brewery in Northern Virginia and had a chance to try their new Raspberry Wheat. It was very nice. There was a nice fruit aroma and then some fruit flavor but the finish was good crisp clean beer. They use fruit extract and if I remember right they add it to the bright tank, nothing in the fermenter. They use their regular ale yeast and ( I can't remember) maybe 40 or was it 60% wheat. The beer was light bodied with a nice hop balance. Probably the best micro fruit beer I've tried. FWIW Rick Pauly Nuc Med Tech Charlottesville,VA Return to table of contents
From: KennyEddy at aol.com Date: Thu, 25 Jul 1996 08:30:24 -0400 Subject: Re: What's Aeration Mike Spinelli asked about aeration of wort: > So what is it? Am I shaking my ass off for nothing? Does the yeast care what > method is used? If aeration means adding more O2 than is already in the wort, > than why even shake? Aeration is the mixing of air in the *cool* (<85F) unfermented wort, to dissolve as much oxygen as possible. The oxygen is used by the yeast in its growth phase. Good aeration promotes faster growth (less chance of infection) and healthier yeast (less off-flavors, fewer stuck-ferments). Much of this was debated in detail here recently by the HBD Yeast Gurus. In HBD1928, A. J. deLange (where are ya, boy?) did an experiment to determine the effectiveness of shaking vs aquarium-pumping with a stone vs O2 with a stone. He was able to measure dissolved oxygen relative to saturation for each method. Following is a brief summary: "In a recent experiment I found the following levels of dissolved oxygen (relative to saturation) in 2.5 gal of water in a 5 gallon carboy (1) shaken VERY vigorously; (2) aerated with compressed air bubbled through an airstone with gentle swirling and (3) pure oxygen bubbled through an airstone with gentle swirling: Time Shaking Compressed Air Oxygen 1 minute 55% 40% 85% 2 70 62 145 3 75 75 - 4 80 82 5 82 90 6 84 92 8 87 98 " He also mentioned that dissolved O2 was about 7% at the start in all three experiments. Now, the question is, how much oxygen (realtive to saturation) is "enough"? If 70% is good, then any of these methods is adequate. If 100% is needed, obviously a different answer results. When I first "discovered" aeration, I used the splashing-siphon method. Then I went to the shake-the-carboy routine, followed most recently by a "Venturi tube" on the fermenter fill tube from the boiler to the carboy. I noticed a big difference in taste and lag time going from no aeration to splashing-siphon, but little difference in taste thereafter (though lag time is shorter still with the Venturi tube). Either the O2 from splashing is adequate or my latest technique is not hugely better than the original. But in any case it's a great improvement over nothing at all!! ********* Ken Schwartz KennyEddy at aol.com http://users.aol.com/kennyeddy Return to table of contents
From: wa5dxp at worldnet.att.net (Jim Overstreet) Date: Thu, 25 Jul 1996 13:03:48 +0000 Subject: Wooden Beer Barrels Many years ago, I purchased two wooden barrels from a local cooper for making beer. He informed me that beer barrels were always lined with a coating of paraffin (wax). I saw him do the coat as I was there when he finished assembling my two kegs. He coated all interior surfaces with melted wax and a torch before assembling the final end piece, then poured the flaming melted wax in through the bung to seal up the end and swished it around. I am sure there was an art to doing this just right, but he made it look simple. At the time he showed me charred barrels he made for people who liked to further age their whiskey. In previous articles I have seen refrence to "brewer's pitch" coating the kegs holding IPA for it's long journey to India. It was probably some type of pitch with the volatiles boiled out so the beer's flavor would not be contaminated. Or, perhaps this pitch was a contributing factor to the unique East Indian IPA flavor some are trying to re-capture? As paraffin is also a petroleum byproduct, could brewer's pitch and paraffin be the same coating? The life of these barrels was probably short-lived, as there was no liquid in contact with the wood to swell it up to maintain the hoop tension. Or, after use, the coating could be removed with boiling water and used in a conventional manner. This could be an interesting subject for a budding brewmaster's research paper. Return to table of contents
From: George_De_Piro at berlex.com (George De Piro) Date: Thu, 25 Jul 1996 08:54:04 -0700 Subject: RE: HSA when decocting, Blue whale ale, Hop pellets Mike Swan asks what Noonan means when he says that boiling the decoction deaerates it. Any air (oxygen) that may have been picked up earlier in the mash will be purged by boiling because the solubility of O2 in 212F water is nil. To tell you the truth, I can't think of why this should matter; if you splash around a lot when adding the decoction back to the main mash, you'll pick up O2 again! The reason you should be concerned about HSA (hot-side aeration) when collecting wort from the sparge is that it will be sitting in your kettle at ~160F for a while during the sparge. This could be enough time for some oxidation of the wort to occur, despite the low solubility of O2 at 160F. By the time you bring it up to a boil and purge the O2, the damage is done. In reality, pro brewers splash like mad as the grain flows into the mash tun at mash-in, and they don't care about it. Just try to keep aeration of the hot mash/wort to as little as reasonably possible, and you'll be fine. Duffy asks if the hop rate of Blue Whale Ale seems a bit high. Keep in mind that I am a malt-head, and firmly believe (from experience) that most "beginner" homebrew is over-hopped, but that's 33 ALPHA ACID UNITS for bittering a 5 gallon batch!!! GOOD GOD!!! If you use pellets the stuff will be incredibly harsh! In fact, even with whole cones, the stuff will be harsh! On top of that, there's a very substantial amount of flavoring hops, and case you still don't get it, it's dry hopped to boot! Further, those high-alpha hop varieties aren't my personal favorites because they can be a bit harsh, even in more reasonable quantities. Definitely back off on the hops, and if you use pellets, back off even more because you'll get higher utilization out of them. A question just occurred to me: in Fix's book "Vienna/Marzen?Oktoberfest he states (sorry, no page # and I'm paraphrasing) that it is generally accepted that multiple additions of hop pellets do not make a difference in their contribution to the beer. Who accepts this? It is directly contrary to my experience. I find that they don't need to boil nearly as long as whole cones, but boiling them for 40 minutes certainly seems to add more bitterness than boiling them for 10 minutes (which adds flavor). Have Fun! George De Piro (Nyack, NY) Return to table of contents
From: RUSt1d? <rust1d at swamp.li.com> Date: Thu, 25 Jul 1996 10:04:24 -0400 Subject: Re: Indoor Propane >I don't understand the paranoia here. A couple of years ago we had exploding >propane tanks up in the very high country where they had record snowfall and >the propane pressure regulators got frozen under a LOT of snow. Then they lost >their seals and leaked a lot of propane into cabins that ended up exploding, >but we're just talking about small tanks inside a basement aren't we? > >I say go for it Mike. > >Charley > Ack! Boy that's some advice. I guess "small tanks" that leak only cause small explosions, which can only start small fires... I say go for it Mike. John Varady Boneyard Brewing Note on HBRCP: If you got it and have problems with fonts, you probably need to install the two fonts that came with it to windows. ************************** ** rust1d at li.com ** ** John Nicholas Varady ** <-- Now Engaged. ** Eve Courtney Hoyt ** ************************** http://www.netaxs.com/people/vectorsys/index.html Return to table of contents
From: Schwab_Bryan at CCMAIL.ncsc.navy.mil Date: Thu, 25 Jul 96 09:02:47 CDT Subject: Cream Stout?? Greetings, I was wondering here ( yeah I have nothing better to do during Uncle Sugars time than to sit and ponder the possibilities of Brewin' that better batch of beer , than to worry about his Defense Systems...) on if it is possible, or even an accepted practice if and when one is brewin' up a Stout to add some powdered Milk to the mash bed? Or is there something more in line and accepted practice when one is brewin up a Cream Stout? I have searched the Cats Meow, as well past issues of Zymurgy and BYOB with out any sucess. I am sur I hae read something in one of these magazines before which gave me the idea but with all that is going on with Defense Buget Cutting and Job security these days my mind is a hazey shade of confusion!! On another note, if anyboby gets over the Victory Brewing Company in Dowingtown PA, it is wort your visit. GREAT BREWS, Good Atmosphere ( some of the waitresses need to lighten up abit though! :) ) Good pizza even. Good Job Jim!!:):):) Bryan Return to table of contents
From: Fred Hardy <fcmbh at access.digex.net> Date: Thu, 25 Jul 1996 10:27:46 -0400 (EDT) Subject: Fruit Flavorings Todd Kirby asks a very good question regarding fruit flavorings found in HB shops. Todd, they are inexpensive and good. Purists will insist that you must use fresh or frozen fruits, and for them that is true. There is, however, an excellent reason to use the flavorings: ease of use. Many of those exponents of real fruit use malt extract instead of all grain for the base beer. Who is kidding who here? A neat way to try these flavorings is bottle 1/2 (or some fraction) of your base brew, add an appropriate amount of flavoring to the bottling bucket, stir, and continue to bottle. You can adjust the amount of flavoring next time if you aren't fully happy with the results. These flavorings are no different than real fruit when it comes to how much is enough? It depends on two things - the beer and the fruit. Darker beers usually mean more flavoring to get the aroma and flavor threshold above the dark malt effect. Fruits such as plums have a much less aggressive flavor/aroma profile than raspberries. Lower flavor profile usually means more fruit, but it depends on the effect you are seeking. Using the split batch approach lets you quickly (relatively speaking) decide if the flavorings work for you, or if you prefer to go the real fruit route. This weekend I will sip a mild cherry ale (English Mild fermented with sweet (Bing) cherries) while I bottle 1/2 of an American pale lager as a pale lager, add peach flavoring (2 1/2 ozs.), and bottle the other 1/2 as a peach lager. Some of us, you see, use both real fruit and flavorings. Cheers, Fred =========================================================================== We must invent the future, else it will | <Fred Hardy> happen to us and we will not like it. | [Stafford Beer, "Platform for Change"] | email: fcmbh at access.digex.net Return to table of contents
From: RUSt1d? <rust1d at swamp.li.com> Date: Thu, 25 Jul 1996 10:46:21 -0400 Subject: Re: Blue Whale Ale Duff sez: >Hop Schedule: >1.25 oz Nugget (14.6%) for 90 min. >1.25 oz Chinook (11.8%) for 90min. >.75 oz Willamette (4.4%) for 20 min. >.75 oz Centennial (10.3%) for 20 min. >.5 oz Perle (6.6%) for 20 min. >.5 oz Chinook (11.8%) for 20 min. >1.75 oz Centennial (10.3%) dryhopped in secondary > Duff, You did good calculating the IBU's. I ran the schedule through HBRCP and came out with 178.2 IBU's. That is bitter! Is it undrinkable? I don't know... That's a matter of what you like. Personally, the guideline I use for too bitter is when the IBU's exceed the specific gravity. The S.G. you should expect is about 1.070, If you would like to match the IBU's to the S.G., use this schedule (Rager's utilization numbers): Name: Blue Whale O.G.: 1.070 Style: IPA I.B.U.: 71.3 Volume: 5.0 gallons A.B.V.: 7.0% Grains/Fermentables Lbs Hops AAU Oz Min Alexanders's LM Extract 8.00 Nugget 14.6 0.50 90 Crystal 40, American 1.00 Chinook 11.8 0.50 90 Crystal 20, American 1.00 Willamette 4.4 0.30 20 Centeninal 10.3 0.30 20 Perle 6.6 0.20 20 Chinook 11.8 0.20 20 .70 oz Centennial (10.3%) dryhopped in secondary John Varady Boneyard Brewing Co. http:\\www.netaxs.com\people\vectorsys\index.html Return to table of contents
From: Scott Dornseif <SDORNSE at wpo.it.luc.edu> Date: Thu, 25 Jul 1996 09:54:02 -0500 Subject: Propane cburns at spider.lloyd.com (Charley) Date: Wed, 24 Jul 1996 22:04:57 GMT writes: <snip> > motten at fcmc.com ([Michael Otten]) asks: >>. ... my concern right now is safety. I have heard all the warnings about not using >Mike: Serious. The concern about Propane is not CO. It is the propane itself. <snip> >Guy Gregory >I've been using propane to heat my house and cook my food in the kitchen for 2 1/2 >years with absolutely no problem (hasn't gon e "boom" yet). Millions of people use it in >rural communities <snip> > I say go for it Mike. > Charley <snip> Take Home Point: Yes propane is dangerous! Yes you can use it safely. Ensure ventilation during use. Store tanks outside. Test connections for leaks, every use. Know what you're using / doing... someone suggested talking to a professional / dealer Scott Return to table of contents
From: Russell Mast <rmast at fnbc.com> Date: Thu, 25 Jul 1996 10:15:58 -0500 Subject: Aeration. > From: paa3983 at dpsc.dla.mil (Mike Spinelli) > Date: Wed, 24 Jul 96 15:18:54 edt > Subject: What is Aeration anyway??? > Me, I shake the shit out of the carboys til I get a nice head ontop. Me, too. I hate having any traces of shit in there. > Am I adding any more O2 than already was in the wort? No. Yes! You are. The gas in the headspace, at least before fermentation starts, is plain old air from the room, about 20% oxygen. When you shake it like that, and the foam rises, the fowm is caused by gas passing through the solution, and entering a colloidal (or maybe suspended?) state. When the gas passes through the solution, some of it will dissolve. That is to say, when you shake it, you -are- dissolving some of the headspace's O2 into the wort. That's how it helps your fermentation go faster. - -R Return to table of contents
From: Michael Caprara <mcaprara at awwarf.com> Date: Thu, 25 Jul 1996 08:13:34 -0600 Subject: Condensation Problems? Hello brewing collective (from beginners to pros) I have a question about condensation in my keg fridge. I have an old 60's model fridge that I use for serving draft homebrew. It is the short, wide type with a small freezer inside. The controller went out about a month a go and I bought one of those controllers with the probe and temp dial. When my fridge starts to get warm, it turns on, and when the desired temp is reached it turns off. During the time it has the fridge running, I build up the slightest bit of ice in the freezer. When the fridge is not running, the ice melts and collects in the bottom of the fridge. It isn't much, but if I don't clean it regularly it can start to get funky in the bottom. I am relaxed and not worried, but some of my friends seem a little hesitant to drink from the tap when there is a little beer/water/funk on the bottom. How (if it is possible) can I keep it from condensating and getting my kegs wet. Thanks. Brewfully Deadicated MC :{P} <---don't want no more wet kegs! Return to table of contents
From: Alan <amf at ktb.net> Date: Thu, 25 Jul 1996 09:24:14 -0700 Subject: Mash tun and extraction testing Beer folk, Most of the designs for coolers turned mash tuns that i've seen use slotted pipe manifolds. I use a ~54Qt rectanglular cooler with a false bottom made from a piece of plexiglass drilled with about 300 1/8" holes. Seems to work great. My question: how food safe is plexiglass? It shows no discoloration after ~8 batches and rinses easily (if i get to it within one day, yuck). During extraction i test with iodine and notice the liquid will quickly stop showing reaction (turning dark purple from starch) but the crushed grains will always turn black. Should i expect to see no iodine starch reaction in crushed grains once i achieve conversion perfection? Thanks. al Beeeeerr! Homer Return to table of contents
From: layton at sh28.dseg.ti.com (Jim Layton 952-3733) Date: Thu, 25 Jul 1996 11:27:09 -0500 Subject: Fruit Fresh Falsehood First, I want to thank the contributors to this digest for providing the wealth of information. My knowledge of brewing continues to grow. In HBD 2121, David Burley states that he, in most cases, sterilizes (?) fruit for brewing fruit beer using Fruit Fresh. He also states that metabisulfite is the active ingredient in this product. Folks, this is not correct. The package label lists dextrose, ascorbic acid, and silicon dioxide. That is all. The label specifically states that this product contains no sulfites. I know that some people avoid sulfites for health reasons and some avoid them for other reasons. I have used Fruit Fresh for its intended purpose, to prevent browning of fruit. I have no experience in using it to make beer but, looking at the ingredients, I doubt that it is very effective at killing bacteria or wild yeasts. If anyone wants to use this product in their beer but is concerned with sulfites, don't be concerned. If you want to sanitize fruit, other methods are available. I have no commercial interest in Fruit Fresh or anything else you may want to put in your beer. Jim Layton layton at antme2.dseg.ti.com Return to table of contents
From: M257876 at sl1001.mdc.com (bayerospace at mac) Date: Thu, 25 Jul 1996 11:53 -0600 Subject: blue whale bitterness collective homebrew conscience: my $.02 on the blue whale bitterness question posed by duffy toler: i have been using two conflicting methods of calculating hop bitterness for about a year now. one is jackie rager's formula, found in the zymurgy 1990 special issue (i think), and the other method is from the hoptech catalog. the biggest difference in these two methods is the utilization factor, which rager states as 30% for a 60 minute boil; hoptech says 20%. gee, are they trying to get me to use more hops???? the other big difference is that hoptech's method cuts off bitterness contribution on a steeper ramp as the end of the boil is approached. rager's formula claims more bitterness can be extracted with under 30 minutes to go. from the looks of the recipe duffy posted, i would say it's probably going to be pretty bitter. but what's the starting gravity going to be? that's a key, and it can't be underestimated (as well as the final gravity). if the beer is relatively unattenuated at the end of fermentation, it can stand to be hopped more aggressively, and in my experience it is sometimes pretty dramatic how much more hops you can put in there without throwing the balance off. i'm not sure i've had any similar recipes to this one. i'm normally not throwing in that much crystal malt for my ales. this could tend to push the final gravity up, which would allow for higher hopping rates. i will make one comment regarding the use of high alpha hops for bittering: i've noticed a bit of a harsher flavor when using galena for bittering as opposed to using lower alpha hops ( for lagers, i normally use liberty to bitter them ). i've seen some recent material in zymurgy that talks to this issue. anybody else out there have this same idea about the high alpha hops? i used to read that "alpha is alpha", but it sure doesn't taste like it to me. these lager batches were virtually identical in every aspect, except for the bittering hops. could it just be the particular hops i used in the recipe? they were '95 galena. (i must apologize if this particular topic has been recently covered. i've only been getting the hbd for a few weeks now. ) hey, what about that decoction mash question i had???? brew hard, mark bayer Return to table of contents
From: "Dave Hinkle" <Dave.Hinkle at aexp.com> Date: 25 Jul 1996 09:42:18 -0700 Subject: Aeration / a fishy story Mike asks: " What does Aerating the wort mean? ... Am I shaking my ass off for nothing? Does the yeast care what method is used? If aeration means adding more O2 than is already in the wort, than why even shake?" Aeration: It's simply dissolving air (hence, more O2) into the wort. Gases can & do dissolve into liquids. Without an aerater / air pump in an aquarium, the fish will suffocate from lack of O2 after a day or two. Even blowing through a straw into a glass of water will aerate it (exhalation is still around 15% O2, the reason why rescue breathing works). The problem with exhalation through wort would be the stuff you expel besides air, such as saliva. Shaking is one of several ways to force more air to get dissolved in the wort. Note that pumping pure O2 into the wort is actually oxygenation, not aeration. Aeration puts other gases (ie. "air") in besides just O2. I don't think the yeast care how the O2 gets in there, as long as it IS in there. I've never read effects of other dissolved gas levels on beer yeast, but I'm sure a yeast rancher has studied it somewhere. Dave Hinkle Phoenix, AZ Return to table of contents
From: korz at pubs.ih.lucent.com Date: Thu, 25 Jul 96 12:05:26 CDT Subject: Wheeler's Porter article Steve writes: >Overall, I think that Al's objections to Wheeler's porter article were too >harsh and generally unfounded. I have brought in my copy of Foster's Porter as well as Dr. John Harrison's Old British Beers and How to Make Them, the Summer 1996 issue of Zymurg (which contains two articles about Porter) and Wheeler/Protz's Brew Your Own Real Ale. Oddly, Wheeler himself perpetuates the Harwood story on page 139! I was wrong about Foster contradicting Wheeler. I've checked all the above sources and there are indeed many stories on how Porter came to be, but all the authors mention that none are definitive. I appreciate the information on Rodenbach from Peter Bouckaert... this extinquishes my skepticism regarding the ties between Porter and Rodenbach. Steve writes: >> For the record, I personally get no acetic (vinegary) character >>in either of the Rodenbach beers. > >You didn't taste the right bottle :-). > >Seriously, there is extremely wide variation from oak barrel to oak barrel >at Rodenbach. A member of our local homebrew club (Sarah White)had a very >personalized tour of Rodenbach a couple of years ago. She walked around >the brewery with Peter, tasting samples from many of the 294 aging barrels. >Sarah reported that the variation between aging tanks was fascinating, one >would be lactic, another acetic, another like New England style cider. Been there, done that... well, I didn't get to taste as much at Rodenbach as Sarah did but I was there and have, over the years, tasted a great deal of both the Rodenbach and Grand Cru. I still assert that I don't smell a noticeable level of acetic acid in either. What I've gathered from my private tour of Rodenbach last summer as well as from reading, that only *selected* vats (barrel is rather a misnomer... these things are nearly 10 feet tall and 10 or 12 feet in diameter!) become Grand Cru. The ones that are in the extreme are used for blending (makes sense, no?). >Al, you also didn't fully quote Wheeler, he clearly stated that the acidity >of Rodenbach Grand Cru may be mellowed by extended aging - this is exactly >the same discussion that has been going on regarding esterification in the >lambic digest. The Brett activity in the aging barrels may be enough to >get the acetic acid level close to or below threshold My point was that in neither product do I get a noticeable level of acetic character... I was not contesting the fact that the beer is acidic. Jim posted data that the lactic was clearly dominant (even in the unlikely extremes: min lactic, max acetic), on average twice to two and a half times more lactic than acetic. If you will recall, I was the *originator* of that thread in the Lambic digest. I'm the one that pointed out that older Lambics and pLambics are less sour most likely due to esterification. My other point was that indeed there are two different types of microbiota contributing the two different types of acids (lactic and acetic), a point that Wheeler was unsure about. He also hailed Guinness's blending-in soured beer as being a new revival while they have been doing it in their stouts for years. There were my greatest gripes and really the only parts of my post that were harsh. Al. Al Korzonas, Palos Hills, IL korzonas at lucent.com Copyright 1996 Al Korzonas Return to table of contents
From: Bob Waterfall <waterr at albany.net> Date: Thu, 25 Jul 1996 13:14:51 -0400 (EDT) Subject: Aeration; Consumption; Propane; Hazelnut Mike Spinelli asks for a clearer definition of aeration of the wort: >Me, I shake the shit >out of the carboys til I get a nice head ontop. Am I adding any more O2 than >already was in the wort? No. The short answer is: Yes you are. You're not wasting your time shaking your carboy. The long answer is: Boiling the wort gets rid of just about all of the dissolved O2. Eventually, wort in contact with air would dissolve O2 from the air to reach equilibrium at about 8 or 9 mg/L (I don't recall the exact number but it has appeared in HBD in the past). The key word is *eventually*. The yeast need the O2 pronto (during the first 8 to 24 hours?). Shaking the wort helps to speed up the dissolution of O2 from the air in the headspace. Using an aquarium pump speeds it up even more. Using an aquarium pump with an in-line air filter reduces the chances of infection. Using bottled O2 speeds it up even more and almost eliminates the chance of infection (from this part of the process anyway). The equilibrium concentration of O2 in the wort is higher by about 5 times for wort in contact with pure O2. Theoretically, you can get your wort dissolved oxygen (DO) level up to about 40 ppm. I seem to recall that this is actually too much for the yeast, but don't quote me on that. Assuming that noone is keeping the wort under a pure O2 blanket though, the DO level would outgas back down to the 8 or 9 ppm level *eventually* even in the absence of yeast or other O2-using organisms. Someone (AJ?) published some experimental data on aerating/oxygenating wort several months ago in HBD. As I recall it showed basicallly what I described above; increasing amounts of DO from boiled wort->shaken wort->aquarium pump->bottled O2 given a reasonable amount of time in treating by each method. Of course, all this has nothing to do with hot-side aeration, which is a Bad Thing. Someone on r.c.b was confused about why, if boiling gets rid of the DO, is HSA from sparging a problem. The answer to that is the DO then gets involved in reactions with components of the wort (melanoidins??). Once those reaction products are formed, boiling won't get rid of them. ************ Bill Rust wonders how much beer to brew for his wedding: Congratulations. For our wedding, we made enough to give everyone a bottle of homebrew (root beer for the kids and non-drinkers) with custom labels by yours truly and ribbons to match the color scheme instead of little bags of candy coated almonds or whatever. That was less brewing but if I never have to tie a bow in another piece of ribbon, it will be too soon. FWIW, this Memorial Day we went through 2 cornys in about 4 or 5 hours with 50 people (including a few kids, non drinkers, winos, and someone who left a few Silver Bullets behind to clutter up my beer fridge). Some friends recently got married, I think they had three cornys and about 100 people and finished it off well before the festivities were over. ************* The basement use of outdoor propane cookers thread once again rears its ugly head: Yes propane is regularly used in rural communities for stoves, dryers, etc. You will notice that the tanks are outside to eliminate the propane pooling in the basement next to a water heater pilot light syndrome. Also, gas lines have (we hope) been fitted by someone who knows what s/he is doing. Also, normal houshold appliances are rated well below the 100,000+ Btu/hr ratings of your typical outdoor cooker. As an air pollution engineer, I would say your biggest concerns would be carbon monoxide from poor combustion (throttled down hole-in-a-pipe type burners) and nitrogen oxides from good combustion (ring burner going full tilt). Unfortunately I don't have any data for propane cookers to back this up. I do have emission factors from USEPA for Liquified Petroleum Gas combustion in commercial boilers (generally 300,000 to 10 million Btu/Hr). They say you should assume NOx (as NO2) at 14 lb/1000 gal fuel and CO at 1.9 lb/1000 gal. The gallons are gallons of vapor, not the liquid fuel. I would assume that we would produce less NOx but more CO than boilers due to the open flame, but I'll use those figures anyway just to get a ballpark figure. Given a typical heating value of 91,500 Btu/gallon, let's assume we burn 1 gallon per hour to make it easy. That's 0.0019 lb CO and .014 lb NOx produced in a 1 hour boil. If your room is about 5000 cu. ft. (about 20'x30'x8')and has minimal ventilation, you would have concentrations of 24.5 ppm NOx and 5 ppm CO. Of course if you have poor ventilation the CO will jump way up (a factor of 500 could be considered typical IMHO). That would put your CO level well over the IDLH (immediately dangerous to life or health) level of 1500 ppm. On the bright side, the levels of NOx would be much lower than predicted when you die of CO poisoning. The IDLH for NO2 is 50 ppm. The applicable workplace standards for these are 35 ppm (8 hr) and 200 ppm (Ceiling never to be exceeded) for CO and 1 ppm (Short Term - 15 min) for NO2. Adequate ventilation can lessen these concerns. But adequate ventilation does not mean having a window open. I'm talking about commercial kitchen range hoods here. "Industrial Ventilation" (17th Ed., Amer. Conf. of Gov. Indust. Hygienists, 1982) recommends 125 cfm/sq ft of hood area for island-type hoods which is about the closest thing they have to our problem. The hood you would need would be about 5 sq ft or so set several feet above the burner. For that size hood then we're talking about at least 625 cfm. That comes out to 7.5 air change-overs per hour which seems low. I would up it to at least 20 changeovers per hour or 1700 cfm. I would also go to more effort than these back of the envelope calculations, but you get the idea. After attempting to copy Longshot Hazelnut Brown (Annetmark at aol.com) Mark Tumarkin says: >I tried them and found the hazelnut extract >flavor to be overwhelming in both. To my taste they are both almost >undrinkable. Really a shame too, as the Porter tastes excellant otherwise. I find the Longshot to be almost undrinkable. It seems that this whole nut flavored extract thing came about because of the term "Nut brown ale" which as we know has to do with the *color* of a certain product from Tadcaster. I will admit that you can find a nutty overtone to the flavor if you really want to, but it's subtle (as it should be IMO). If I want sweet hazelnut flavors, I'll take a small glass of Frangelica or a Ferrero Rocher candy, thanks. Bob Waterfall <waterr at albany.net>, Troy, NY, USA Return to table of contents