HOMEBREW Digest #1540 Fri 30 September 1994

Digest #1539 Digest #1541

		Rob Gardner, Digest Janitor

  A primer on priming (pt 1) (HIBBERD Mark)
  A primer on priming (pt2) (HIBBERD Mark)
  bottle infections... (abaucom)
  Regional Recipe Request (TJWILLIA)
  labels, out of control (HEWITT)
  Mailing beer ("William F. Cook")
  Thanks, Wort-Chiller Wins by a Landslide (ESMPD)" <gcunning at Census.GOV>
  Semi-open fermentation (Allan Rubinoff)
  How to get "dirt cheap" grain (Spencer.W.Thomas)
  Ball Valve Alert (npyle)
  calcium chloride (Jay Weissler)
  King Kooker Kooking (Btalk)
  1st Annual Naked Pueblo Homebrew Competition (Ray Brice)
  Re: Aeration equipment (Dion Hollenbeck)
  light beer. (djfitzg)
  Re : yeast cell lifespan (Mike Twardowski)
  Re: Aeration equipment (KWH)
  Re: Plumbing parts for SS kegs (Joel Birkeland)
  Wyeast 3068 ("Seth L. Betaharon")
  Mature in carboy or bottles? (Jim Blue)
  New Magazine ("Vandermey, John")
  Screening nasties/stuck ferment (Algis R Korzonas +1 708 979 8583)
  Hard Water Brewing (Art Steinmetz)
  Pilsner Urquell Yeast (Jay Weissler)
  Brewpubs in CA (BrewerBob)

****************************************************************** * NEW POLICY NOTE: Due to the incredible volume of bouncing mail, * I am going to have to start removing addresses from the list * that cause ongoing problems. In particular, if your mailbox * is full or your account over quota, and this results in bounced * mail, your address will be removed from the list after a few days. * * If you use a 'vacation' program, please be sure that it only * sends a automated reply to homebrew-request *once*. If I get * more than one, then I'll delete your address from the list. ****************************************************************** Send articles for __publication_only__ to homebrew at hpfcmi.fc.hp.com (Articles are published in the order they are received.) Send UNSUBSCRIBE and all other requests, ie, address change, etc., to homebrew-request@ hpfcmi.fc.hp.com, BUT PLEASE NOTE that if you subscribed via the BITNET listserver (BEER-L at UA1VM.UA.EDU), then you MUST unsubscribe the same way! If your account is being deleted, please be courteous and unsubscribe first. FAQs, archives and other files are available via anonymous ftp from sierra.stanford.edu. (Those without ftp access may retrieve files via mail from listserv at sierra.stanford.edu. Send HELP as the body of a message to that address to receive listserver instructions.) Please don't send me requests for back issues - you will be silently ignored. For "Cat's Meow" information, send mail to lutzen at novell.physics.umr.edu
---------------------------------------------------------------------- Date: Wed, 28 Sep 1994 17:49:55 +1200 (EST) From: HIBBERD Mark <mfh at dar.csiro.au> Subject: A primer on priming (pt 1) I've recently put together some notes on priming for our club newsletter and thought I'd see what response it receives herre. It was inspired by a desire to explain some of the problems I'd been having with priming various styles of beer. Priming notes (part 1) - Mark Hibberd (Bayside Brewers, Melbourne) - ---------------------- Most homebrewers carbonate their beer by adding priming sugar at bottling time. Usual instructions call for about a teaspoon of sugar per bottle. But exactly how much sugar is needed and what types of sugar are suitable? And what can you do if a beer is over- or under-carbonated? Carbonation levels The amount of carbon dioxide in a beer can usefully be described in terms of the volumes of CO2, i.e. how many volumes of CO2 (at atmospheric pressure) are dissolved in one volume of beer. This terminology is familiar to those who keg. Charts for kegging systems show the gas pressure to apply at each temperature to achieve a particular carbonation level. If this pressure is held for several days, the carbonation reaches its equilibrium value, i.e. the beer will absorb all the CO2 it can at that temperature. In bottle conditioning, the CO2 is produced by the fermentation of an accurate dosing of priming sugar. Just as each style of beer has its own balance of hops and maltiness, so the appropriate level of carbonation varies from beer to beer. British ales should be much less carbonated than lagers or wheat beers. The accompanying table shows typical carbonation levels for various styles of beer. Exact values are a matter of personal preference, but a good starting point for a homebrew is 2.4 volumes CO2. Beer style Volumes CO2 ---------- ----------- British-style ales 1.8 - 2.2 Most lagers, Aussie beers 2.2 - 2.6 American, highly carbonated 2.6 - 3.0 Typical CO2 levels in bottled beers How much priming sugar To achieve a particular carbonation level, you need to know the initial CO2 content of your 'green' beer as well as the amount of priming sugar that will give the additional CO2. Green beer, i.e. beer that has finished fermenting and is ready for bottling, is saturated with carbon dioxide because it has had CO2 bubbling through it continuously during fermentation. This amount of CO2 can be estimated from the accompanying graph. It shows that the CO2 level depends on the temperature (at which fermentation was completed) and explains why a sample taken from a secondary fermenter at 2 degC tastes much brighter than a sample from an ale fermenting at 20 degC. For the following example, we will assume an initial 0.9 volumes CO2. Temp (degC) Vol. CO2 Temp (degC) Vol. CO2 ----------- -------- ----------- -------- 0 1.7 12 1.12 2 1.6 14 1.05 4 1.5 16 0.99 6 1.4 18 0.93 8 1.3 20 0.88 10 1.2 22 0.83 Chart substituted here for graph in original article Determining the amount of priming sugar is based on the fact that adding 4 grams of fully fermentable sugar (dextrose, glucose or normal white sugar) per litre will ferment to give 1 volume of CO2: 4 g/l sugar --> 1 vol. CO2 For our sample homebrew with a final 2.4 volumes CO2, we subtract the initial 0.9 vol. CO2 in the green beer to find that we need another 1.5 vol. CO2. This is achieved by adding 1.5*4 = 6 g/l priming sugar. It can be added directly to each bottle (4.5 g per 750 ml bottle) or by bulk priming the whole batch. For bulk priming (in this example, 140 g for a 23 l batch), the sugar is dissolved and sanitised by boiling in about 500 ml water, then cooled and added to a clean fermenter. The green beer is then racked into this fermenter, carefully mixed and bottled. Bulk priming has the advantages of sterilising the sugar, consistent carbonation for all bottles and not having to worry about siphoning yeast sediment at the end of bottling. Balanced against this are the risks of oxidation and infection with the extra racking as well as the additional time involved. Variations in the priming rate as small as 1 g/l can produce noticeable changes in the final CO2 levels (0.25 vol. CO2) so that fairly accurate measurements are required to obtain consistent results. For comparison with the priming rate suggested above, it is useful to note that the 3/4 cup corn sugar (4 oz. dry weight) per 5 U.S. gallons called for in many American recipes is equivalent to a priming rate of 6 g/l. This simple picture can be complicated by the CO2 generated by the slow breakdown and fermentation of dextrins, particularly in strong all-malt beers. This is rather difficult to estimate. Although it will be negligible in most beers, it is said to be sufficient to fully carbonate some high gravity beers that are stored many months before drinking (maybe producing up to 1 vol. CO2). (continued in part 2) Return to table of contents
Date: Wed, 28 Sep 1994 18:22:36 +1200 (EST) From: HIBBERD Mark <mfh at dar.csiro.au> Subject: A primer on priming (pt2) Priming notes (part 2) - ---------------------- Measuring priming sugar The most accurate method of measuring priming sugar is by weight but for bottle priming the most convenient method is by volume using a measuring spoon. However, much confusion arises here because the same spoon holds different weights of different sugars. Measurements show that a standard (5 ml) kitchen teaspoon holds 4.5 g of normal white sugar but only 3.4 g of dextrose or glucose powder - about 25% less dextrose. This difference is sufficient to explain the changes homebrewers report when switching from one priming sugar to another, particularly as many kit recipes suggest rather high priming rates to produce a beer ready for drinking soon after bottling; these beers often become over-carbonated with time. Another useful 'spoon' is a homebrew bottling measure, which holds 6 g of white sugar (4.5 g dextrose) on one side and 3 g (2.3 g dextrose) on the other. Thus, either a standard teaspoon of white sugar or a bottling measure of dextrose per 750 ml bottle will give the same final level of carbonation (+1.5 vol. CO2). But if the sugars were reversed (teaspoon of dextrose or bottling measure of white sugar), the final beer would be under- or over-carbonated by 0.4 vol. CO2. For really reliable results, you need to know exactly how much priming sugar your measuring spoon holds. If you have accurate scales, you can check directly. However, it's best to average by adding, say, 20 scoops to a small container and weighing them all at once. If your scales aren't accurate enough, you could ask your homebrew shop to do the weighing. Or buy some good scales - they're also useful for weighing hops and letters! Types of priming sugar The above calculations are based on using fully fermentable sugars. These include glucose, dextrose (corn sugar), fructose, and sucrose (white sugar or castor sugar). Icing sugar should be avoided because of the small amounts of cornstarch added to prevent clumping. In fact, a given weight of sucrose produces 5% more CO2 than the other sugars, but the difference can safely be ignored. When used in small amounts for priming, none of these sugars contributes any flavour to the beer. On the other hand, some people enjoy the note added by using brown sugar or Demerara sugar to prime ales; the same weights should be used as for dextrose. For the adventurous, syrups can also be used, but the weights need to be increased to account for the water and different types of sugars present: honey (extra 40% by weight), genuine maple syrup (+50%) or molasses (+80%). Furthermore, the results will be less predictable and carbonation will take longer. Finally, the all-malt purist may want to prime with malt extract, either dried (+30%) or liquid (+40%). Again the results may be variable. More involved methods include adding unfermented or actively fermenting wort (krausening); details can be found in good brewing books. Problems Sometimes things just don't work out and you find a whole batch is over- carbonated. It may have occurred because of bottling too soon, over- priming or possibly because of an infection. In any case, the batch can be saved by releasing some of the pressure. With swing-top Grolsch bottles, just release the pressure momentarily a number of times over several days. For crown-sealed bottles, it's best to cool them as much as possible to avoid gushing. Prise off the caps but leave them sitting loosely in place to minimise possible contamination of the beer. The time to wait before resealing with new caps can only be determined by trial and error so experiment with one bottle at a time, starting with 10 to 30 minutes. On the other hand the beer may be under-carbonated or even flat. The simplest explanations are that you forgot to prime or that the caps are not sealing properly. But it may also be that they just haven't had time to carbonate properly in which case you'll probably be able to taste the sugar. The bottles should be held at the yeast fermentation temperature for a few days for an ale yeast to several weeks for a cool-fermenting lager yeast. A longer time may be required if the beer sat for a long time before bottling allowing more of the yeast to sediment out. But there should always be enough yeast left to do the job provided they are given sufficient time. If you're really worried, it is possible to add extra yeast - a few grains of dried yeast or drops of liquid yeast. But extra priming sugar should only be added as a last resort if you want to avoid producing a batch of grenades. In conclusion, a teaspoon of sugar per 750 ml bottle is a good rule of thumb and if you're happy with the result then stick with it. But if you're having problems, the factors discussed here should enable you to consistently produce beer that is carbonated the way you like it. Return to table of contents
Date: Wed, 28 Sep 94 7:35:03 EDT From: abaucom at fester.swales.com Subject: bottle infections... I once read that if you have a ring around the neck of your bottles (at the liquid line) that was undeniably an infection signal... I have some mead that has been bottled for about 6-8 months and before that it was in a secondary for 6-8 months...Here's the wierd thing... all the mead bottles have a thin white consistant ring right at the liquid line but the mead is FANTASTIC... If it IS infected...then 3 cheers for infections... So my question is the obvious...is there other explainations for a bottle ring besides infections? Thanks... Andrew - ------ Andrew W. Baucom, abaucom at fester.swales.com Return to table of contents
Date: Wed, 28 Sep 94 08:25:17 EDT From: <TJWILLIA%OCC.bitnet at CUNYVM.CUNY.EDU> Subject: Regional Recipe Request Risking the flames ... For those in Michigan (or close by), does anyone know of a clone of Sol Sun out of the Kalamazoo Brewing Co.? I know that this may vex those far removed from these environs, but if I can come up with this I may just have a new convert for this noble hobby. Extract or all-grain. E-mail just fine. TIA Tom Williams tjwillia at occ.bitnet Return to table of contents
Date: Wed, 28 Sep 1994 08:45 EDT From: HEWITT at arcges.arceng.com Subject: labels, out of control Three cheers to Nuttings Lake Publishing. Good service deserves highlighting to fellow users. I recently made my first order for beer labels (ad in Zymurgy) and recieved my order priority mail almost before the check cleared. Very refreshing. (no affiliation, etc.) Are you listening psycokitty? On another subject, on my next lager batch I am considering an approach to more accurately control fermentation temperature. Rather than mounting the Hunter controller sensor on the inside of the refrigerator, I am planning on mounting it on the side of the carboy and taping insulation on the backside. I will monitor the fridge temp and carboy temp with time to document the results. To avoid a large undershoot in cooling to fermentation temperature I will wait until the wort and starter have stabilized at the desired temp, pitch, switch the sensor to the carboy, and let the controller compensate for the heat generated by fermentation. Five gallons of high density wort may be too much of a thermal mass to control effectively with only free convection, but I will give it a shot. Anybody tried something similar before I burn up my compressor? Pat Hewitt "Don't let the same dog bite you twice" - Tesla Return to table of contents
Date: 28 Sep 94 08:43:41 EDT From: "William F. Cook" <71533.2750 at compuserve.com> Subject: Mailing beer Please forgive if this is in a FAQ or zymurgy somewhere...I haven't found it in the stuff I have access to. What is the proper way to mail homebrew, wrt legality and shipper policies? I've heard that UPS & post office will not ship beer. Private e-mail is fine, I will summarize and post. Thanx in advance, Bill Cook HydroComp, Inc. Team Dennis Conner Return to table of contents
Date: Wed, 28 Sep 1994 08:52:35 -0400 (EDT) From: "Jerry Cunningham (ESMPD)" <gcunning at Census.GOV> Subject: Thanks, Wort-Chiller Wins by a Landslide Hello everyone, I read Bob the Badgerspace guy's article today saying that thanks are in order for people who respond to your questions (I didn't know if I should send thanks or not). I decided to thank everyone who responded to my "wort-chiller vs. secondary" question, but I lost their addresses, so I'm gonna do it in public! Thanks Jeff D., jc, CLAY, Darren Aaberge, Steve Peters, Al.K, Ralph Griffin, Paul S., Rick Magnon, and Steve Turner. I really appreciate your comments, and sorry if I forgot anyone. To summarize, my question was which piece of equipment would have a bigger impact on improving my brews. The responses were 2-1 in favor of the wort- chiller, so naturally I went out and bought a carboy! Here's my "logic": Winter is coming so my wort will cool faster, and with a glass carboy as a secondary I can bottle _when I want_! I do plan on building a wort-chiller in the future, though. Thanks again. P.S. I also received 2 geography lessons telling my that Checkoslavakia (sp?) has split into 2 countries. Yeah, right, next thing you'll tell me the Soviet Union split up. Jerry Cunningham Annapolis, MD Return to table of contents
Date: Wed, 28 Sep 94 09:13:40 EDT From: Allan Rubinoff <rubinoff at BBN.COM> Subject: Semi-open fermentation After all this discussion lately of exploding and shattered carboys resulting in loss of life and limb, I'm starting to reconsider my brewing procedure. I brew three-gallon batches, which I ferment in a five-gallon carboy. Since this leaves a great deal of headspace, I just attach a stopper and airlock for the entire fermentation. The krausen sometimes gets pretty high, but has never reached the airlock. The next two brews I'm planning, though, will be pretty high gravity, and I suspect I'll get a pretty vigorous fermentation. I don't want to risk having a clogged airlock. I also don't want to bother with a blowoff hose. So, I'm thinking of using the following procedure: - After pitching the yeast, attach stopper and airlock. - When krausen starts to build up, remove stopper and airlock, leaving carboy open. - After krausen begins to die down, reattach stopper and airlock. I figure it's OK for the carboy to be open during high krausen, because the wort is well protected by the CO2 being blown off. And this way I avoid the chance of the airlock clogging. The worst that could happen is a little krausen overflowing out of the carboy. Can anybody see a problem with this approach? Should I at least loosely cover the carboy, to keep spiders out of my beer? Thanks, Allan Rubinoff <rubinoff at bbn.com> Return to table of contents
Date: Wed, 28 Sep 94 10:01:56 EDT From: Spencer.W.Thomas at med.umich.edu Subject: How to get "dirt cheap" grain It worked for us, anyway. Step 1: Find a friend who has a business, so they can order wholesale. Step 2: Call Schreier (or other maltings, I imagine) and get a current price list & spec sheet. They had a big ad at the back of the most recent Brewing Techniques. Step 3: Canvas your friends for 50-100 lbs of grain each (1-2 bags). Step 4: Wait until you've accumulated an order for at least 1000 lbs. Step 5: Have friend's business order grain from maltings. Step 6: Enjoy! We did this recently (I picked my grain up Monday evening). We managed a 2000 lb order (1000 lbs is the minimum from Schreier, there's another price break at 1500). I got a bag of DWC Belgian Pale Ale malt and one of DWC Belgian Pilsner for $23.50 & $23, respectively (< 48c/lb). Specialty malts (CaraVienne, Munich, Aromatic) came in at 48c/lb. These prices include shipping (10c/lb to Ann Arbor). If I had "settled" for the Schreier 2-row malt (a "lager" malt, it appears from the specs), my cost would have been about $19/bag (38c/lb). If you don't have a friend with an appropriate business, you may be able to coerce your local HB shop owner into a bulk special order with minimal mark-up. =Spencer in Ann Arbor, MI Return to table of contents
Date: Wed, 28 Sep 94 8:44:57 MDT From: npyle at hp7013.ecae.StorTek.COM Subject: Ball Valve Alert As a followup to this, from John Palmer, about ball-valves: >On ball valves; I have noticed several varieties. Many are imported from >Italy. The ball valve I finally selected was forged brass, chrome plated and >used >Teflon seals around the ball. It is manufactured by B&K and distributed by >Ace >Hardware. I like it. I mounted it 4 inches out from the keg to get it away >fromthe heat of the propane burner the keg sits on. I've found out the hard way about getting wrong type of valve. The valve I used on the outlet of my kettle was a gas valve, which I didn't think much of at the time. It is a brass valve, might be made by B&K (not sure), with a SS ball in a black rubber socket. I suppose the rubber gives a better seal at gas pressures. Well, after a year of service, I started to get infection problems. It took several tries to realize the root of the problem is the ball valve itself. The rubber deforms slightly when the valve is opened and closed, which is a great trap for spare wort, which is a great home for all kinds of microscopic beer-killers. Oh, but the heat of the boiling wort should kill that, you say? I said that too, but I suspect the rubber makes a fair heat insulator to allow the little guys to thrive, or at least survive. No amount of boiling water run through this thing managed to take out this infection. The solution is to use a liquid ball valve, as John suggests. These have a "hard" socket for the ball to rotate in. John says his is made of teflon; I believe these look like a white plastic socket. I'm pretty sure I've also seen them in brass sockets, but I can't say for sure. The point is that the ones containing rubber will eventually cause problems, so keep it in mind. Cheers, Norm npyle at hp7013.ecae.stortek.com Return to table of contents
Date: Wed, 28 Sep 94 09:51:30 -0500 From: jay_weissler at il.us.swissbank.com (Jay Weissler) Subject: calcium chloride Every so often I get the urge to screw-up the perfectly good brewing water found here in the Chicago North Shore. For those not familiar with it, we have moderately soft water (about 130) with a high pH (7.6-7.8). The hardness is almost all temporary. I rarely pre-boil, because of the low mineral content and instead usually acidify. I thought it would be fun to mess up a few lagers with Calcium Chloride. Anyone have any experience with this stuff? Any advice, suggestions, recommended procedures, etc? TIA jayw Return to table of contents
Date: Wed, 28 Sep 94 11:18:05 EDT From: Btalk at aol.com Subject: King Kooker Kooking Mark Montminy asks about flame adjustment and stuff burning on pot bottom. FWIW, heres what I do. I've noticed that if the 'air' vent is opened too much proportional to the gas that the flame sorta lifts off of the burner. I close the 'air' vent so the flame barely sits back down. It is also quieter. No yellow flame ever. I figure that running a bit lean will get maximim btus from the propane. Any other thoughts on this? Regarding pot scorching- Keep stirring while on high heat, or raise heat a little at a time stirring once in a whle to keep things moving. I still have a little cooked on area in the bottom of my keg kettle. What do other people do for a flame spreader/ diffuser for a keg & Kooker set up? Regards, Bob Talkiewicz,Binghamton,NY<btalk at aol.com> Return to table of contents
Date: Wed, 28 Sep 1994 08:28:36 -0700 From: Ray Brice <ray at hwr.arizona.edu> Subject: 1st Annual Naked Pueblo Homebrew Competition Greetings, The 1st Annual Naked Pueblo Homebrew Competition will take place November 19th at: Gentle Ben's Brewing Co. 841 N. Tyndall Tucson, Arizona 85719 (602) 624-4177 First Round Judging will begin at 1:00. Best of Show Judging will begin at 4:00. Awards ceremony will begin at 6:00. This is an AHA sanctioned competition with 10 main categories and 21 subcategories. Please contact Ray Brice (602-744-6688; ray at hwr.arizona.edu) or John O'Neal (602-622-4004; JohnmO123 at aol.com) for free entrants packet. Winner's of each category will receive a commemorative pint glass. 2nd and 3rd place in each category will receive ribbons. Best of Show winner will receive a gift from a local sponsor, pint glass, plus the opportunity to brew a batch of beer along with the head brewer from Gentle Ben's Brewing Co. Runners up to Best of Show will receive a gift from a local sponsor. Cheers, Ray Brice Return to table of contents
Date: Wed, 28 Sep 94 09:12:01 PDT From: hollen at megatek.com (Dion Hollenbeck) Subject: Re: Aeration equipment [...question about filtration of aeration air...] Don't have direct experience, but I was just re-reading a back issue of Zymurgy, special issue on Yeast Propagation and one article talks about building a glove box for doing propagation chores. It talks about a way to use an aquarium pump for creating a positive pressure in the box and tells how to sterilize the air pumped in. Dion Hollenbeck (619)675-4000x2814 Email: hollen at megatek.com Staff Software Engineer Megatek Corporation, San Diego, California Return to table of contents
Date: Wed, 28 Sep 94 12:31:19 EDT From: djfitzg at VNET.IBM.COM Subject: light beer. This may be of general interest to a few of you who have the pleasure of being both a homebrewer and a family man. My wife has been asking me to brew a beer to her liking for a few months now, Mary has a fondness for american light beers. So 3 weeks back i gave it a shot. It is an all grain recipe, but is very easy to do in a 5 gallon pot on top of the stove, anyone who hasnt tried all grain shouldnt have a problem with this one, i used papazians step mashing procedure. ingredients for 5 gallons: 3 lbs 2 row lager malt. 2 lbs 2 row pale 1 lb rice 1 oz saaz hops 2 tsp irish moss 1 pkg brewers secret ale yeast. sg. 1.036 fg. 1.004 Make a yeast starter the day before. all grains should be cracked, and rice needs to be pre-cooked before starting the mash, i under-cooked slightly. follow a step mashing process with a 20 minute protien rest at 120-122 deg. After 3 weeks this beer is light and refreshing, Mary loves it and finds it to be similar to her favorite light beers. My wife is drinking homebrew while I attempt a celis white clone...Theres peace in the kitchen again... Enjoy, and happy brewing, Dan Fitzgerald djfitzg at vnet.ibm.com Return to table of contents
Date: Wed, 28 Sep 1994 13:13:42 -0400 (EDT) From: Mike Twardowski <mtwardo at gsosun1.gso.uri.edu> Subject: Re : yeast cell lifespan Date: Thu, 22 Sep 94 23:32:01 EDT From: RaceBrewer at aol.com Subject: yeast cell lifespan Hi Gang, I have an odd question for the microbiologists out there. Does anyone know the lifespan of a single yeast cell under ideal conditions? Not the lifespan of a culture or how long it will survive in a dormant condition... But just simply, from birth to death, under normal conditions, how long will one of Man's Best Friends live? (Technical references appreciated) Sorry, no prizes for the correct answer... Just my thanks. John "RaceBrewer at aol.com" Mulvihill **REPLY** 9/28/94 John at RaceBrewer at aol.com, Interesting question. I think it would be difficult to find any microbiology literature out there giving you a mean lifespan for a yeast cell, but my curiousity has led me to offer this estimation, the merits of which you can determine. The life cycle of a healthy yeast cell is complicated by the fact that when there are plenty of substrates to grow on (sugar, i.e.), the yeast buds asexually, but when the yeast is starved it will reproduce sexually where a full set of chromosomes splits in half to form "haploid" cells in the same manner that humans form sperm and eggs. Haploids can then fuse to make "diploids" which can then bud asexually again. Luckily, we can simplify the situation by assuming that by "normal conditions" you mean the exponential growth phase in a culture, the time span where the yeast are growing at the maximum rate possible. This occurs right after the lag phase (just pitched the starter) when the culture has acclimated to conditions in the fermentation vessel. Now we can assume the population is growing primarily by budding. >From the general microbiology book edited by Prescott et al. (1990), I quote, "Each time a yeast produces mitotically [i.e., budding], it gets a bud scar. When it no longer has any unscarred area through which to bud, it dies. [p. 510]" I estimate (from looking at the buds in the textbook) that an average yeast cell could support about 10-15 bud scars over its surface area. I am going to use 10 here. This value is probably the biggest question mark in this calculation and you can change it accordingly to get different results. >From the same textbook, p. 114, it is given that the mean time it takes a population of S. cerevisiae to double in cell numbers is 2 hours. Assuming only budding is going on in the culture, it should then take 2 hours for each bud to become its own entity. So, it would take **20 hours** for a rapidly growing yeast cell to bud 10 times, after which it would die. If we assume that after it's budded itself to death it could still survive another generation time or so, then we're looking at 22-24 hours before the spent soul sinks to its doom. Hope this helps! Although you specifically asked for no replies about the lifespan of a dormant yeast cell, I have to add to this discussion that in the dormant state a yeast cell can survive hundreds of years. Have you heard of the English Flag porter brewed with a yeast culture isolated from a bottle of beer found on a shipwreck? The wreck dates back to 1825. Incredible! I can't wait to taste it. -Mike Twardowski, mtwardo at gsosun1.gso.uri.edu Graduate student at U.R.I. Return to table of contents
Date: Wed, 28 Sep 94 11:33 From: KWH at roadnet.ups.com (KWH) Subject: Re: Aeration equipment In HBD 1538, Martin Lodahl discusses his wort aeration setup: ....text deleted >contribution to Brewing Techniques: A small widemouth bottle with >a 2-hole stopper, a long tube going through one hole that nearly reaches >the bottom, and a short tube in the other hole. Run tubing from the pump >to the long tube, and from the short tube to the airstone. Fill the >bottle about half-way with mild hydrogen peroxide solution or cheap >vodka, and bubble the air through it. Works fine. I saw the text and graphic of this setup in BT #2 a while back and wanted to build this. The text said that even if some hydrogen peroxide was pushed into the wort, it would not hurt it. I was very skeptical about this, and this has kept me from using this technique. If this is not a concern, I will *gladly* put a crowbar in my wallet and make one of these ASAP. I do not enjoy shaking carboys at the end of an already long brew day. One question - how mild a solution is used? Do you simply dilute with a certain amount of water? Secondly, the graphic in BT showed a second airstone in the jar with peroxide. Is this necessary, or could you simply bubble the air through the end of the tubing? Kirk Harralson kwh at roadnet.ups.com Return to table of contents
Date: Wed, 28 Sep 94 10:58:51 MST From: birkelan at adtaz.sps.mot.com (Joel Birkeland) Subject: Re: Plumbing parts for SS kegs In Homebrew Digest #1538 (September 28, 1994), John Palmer wrote: >I found that I could easily obtain stainless pipe, but had no end of trouble >getting it threaded. Solution was to purchase copper soldering fittings that >were threaded to NPT for the chrome plated brass ball valve and silver solder >those over the SS pipe. For those of you with a McMaster catalog, note that they sell type 304 Stainless pipe nipples. I don't know if these will work, but I thought I would let you know. For my own 15 gallon boiler, I simply drilled a hole in the side of the pot, and inserted a Swagelok bulkhead fitting. A "fiber" washer on the outside, made from some microwave circuit board, makes it seal very well. Just a thought for those of you who do not have access to a welder or don't want to weld. Joel Return to table of contents
Date: Wed, 28 Sep 1994 14:51:35 -0400 (EDT) From: "Seth L. Betaharon" <sethb at wam.umd.edu> Subject: Wyeast 3068 Sometime during the next two weeks I hope to brew another batch of my favorite brew to date: a dunkelweizen. The first time I brewed it I used Wyeast 3056 Bavarian Wheat yeast. This time, though, I want to try Wyeast 3068 Wheihestaphen (sp??) yeast. Recently I have seen many posts concerning this yeast, but in none of them did I see any recomendation as to what a good fermentation temperature is for this yeast. I saw several posts that mentioned fermenting at 55F, but this seems awfully cool to me for an ale yeast. Can anyone out there make any suggestions. Thanks in advance, Seth L. Betaharon sethb at wam.umd.edu Return to table of contents
Date: Wed, 28 Sep 94 14:52:20 -0400 From: blue at cam.nist.gov (Jim Blue) Subject: Mature in carboy or bottles? I'm making an imperial stout, and I know that it will take months to reach its peak of perfection. After the secondary or tertiary has stopped bubbling, should I bottle or wait longer? What's the difference in quality between maturation in the carboy or in the bottle? (I realize that too much time in the carboy and too much of the yeast may drop out, and I could have to add more yeast at bottling time.) Return to table of contents
Date: Wed, 28 Sep 94 13:43:00 PDT From: "Vandermey, John" <JAVANDER at p06.dasd.honeywell.com> Subject: New Magazine I came across a new publication last week that I thought was very well done. It's called "Beer, the magazine". It has a lot of interesting articles ranging from brewing stone beer, to brewpubs in Quebec, to a visit to the Orval brewery. The articles were well written, informative and entertaining. I found my copy at my local grocery store. If anyone wants more information, e-mail me, and I will get back to you. John (javander at p06.dasd.honeywell.com) No affiliation, just enjoyed the magazine... Return to table of contents
Date: 28 Sep 94 19:43:00 GMT From: korz at iepubj.att.com (Algis R Korzonas +1 708 979 8583) Subject: Screening nasties/stuck ferment Martin writes: >> Question #2: What is a good filter material to screen out the nasties >> before they contaminate my precious fluid? And where can it be obtained? > >This is a very legitimate concern, in my opinion. I've seen frequent >references to 0.2 micron filters being used for the purpose, but I've >just used the method that I got, if I recall, from Pete Soper, a >much-missed HBD contributor of years ago, and have since seen in a >contribution to Brewing Techniques: A small widemouth bottle with >a 2-hole stopper, a long tube going through one hole that nearly reaches >the bottom, and a short tube in the other hole. Run tubing from the pump >to the long tube, and from the short tube to the airstone. Fill the >bottle about half-way with mild hydrogen peroxide solution or cheap >vodka, and bubble the air through it. Works fine. Although this appears to kill nasties in the air, if you think about it a bit more, it doesn't. Let's think of nasties in the air as riding on dust particles (like those ones you see floating around Sunday morning as you read the paper -- you know what I'm talking about). As the dust-filled air travels down the tube and into the H2O2, it forms a bubble... a little sphere full of dust particles. When it rises to the top and bursts, it releases its cargo of dust into the headspace of the jar. From there it's just a short ride through a few more tubes to the wort. There is no reason for the H2O2 or alcohol to actually kill anything inside the bubbles. If you want to minimize nasties in your air, you will have to put something like a 0.2 micron in-line filter into your air line. Perhaps if you stuffed cotton into the widemouth bottle instead of putting H2O2 or alcohol into it. Then, maybe you would catch some of the airborne particles. I don't know what the effective pore size would be of a jar full of cotton. Disclaimer: I'm not a biologist -- I used my knowledge of physics, not biology, to come to the conclusions above. ******** gee writes: >If / when your fermentation is >stuck, do you usually pitch another batch of yeast, or do you go ahead and >bottle it? Why? Is what you do dependent on the gravity? I've heard (and >read) arguments either way. I'm curious because my last two batches have >gone kaput at around 1.033-36 (from 1.072-76). This sounds like a candidate for a FAQ -- many have experienced this problem and posted questions about it to the HBD. "Stuck" fermentations are usually caused by: 1. very unfermentable wort, 2. insufficient nutrition for the yeast, 3. temperature shocks, 4. high alcohol levels AND insufficient oxygen for the yeast, 5. high alcohol levels AND insufficient starter size, 5. very high alcohol levels, or 6. overly-flocculent yeast. I put stuck in quotes above, because #1 and #5 are not really stuck ferments. They are frankly, what is expected. The order of the reasons, is based upon the frequency I've encountered among my fellow homebrewers. First of all, if the yeast poops out you should first determine if you are close to the expected apparent attenuation for the yeast (see the yeast FAQ). If you are, then nothing you will do, short of adding a more attenuative yeast will get the gravity to drop any further. You calculate the apparent attenuation by using the following formula: %ApparentAttenuation = (1 - (FG - 1)/(OG - 1)) * 100 So, for example, if your OG was 1.050 and your FG was 1.012, then: %ApparentAttenuation = (1 - (1.012 - 1)/(1.050 - 1)) * 100 = (1 - 0.012/0.050) * 100 = (1 - 0.24) * 100 = (0.76) * 100 = 76% apparent attenuation The most common cause is really a very unfermentable wort. Usually this is caused by using a malt extract such as Laaglander dry or "Dutch" dry malt extract. With these two extracts, I have known brewers to experience apparent attenuations of only 55%. Insufficient nutrition is common only among beers that are made of very large percentages of corn sugar, cane sugar, rice sugar or honey. When making meads, some kind of yeast nutrient is virtually mandatory. The best solution, in my opinion, is to decrease the percentage of these nutrientless sugars and use more malt, but the easiest solution is to add yeast nutrient. Chances are that, even if you are trying to make an American Light Lager, your beer will taste a lot better if you don't overdo the adjuncts. Temperature shocks (sudden changes, downward usually, in temperature) can cause yeast to flocculate out early and settle on the bottom. The solution is to warm up the batch into a comfortable range for the yeast you used (ale or lager) and then stir the yeast up into suspension again somehow. If you are trying to make a barleywine or a triplebock and your yeast poops out, you must ask yourself: "Did I aerate enough?" and "Did I use a big enough starter?" There's no way for me to tell you how much aeration is enough, but I use at least a 2 liter starter for OGs over 1080 or so and a 4 liter starter for OGs over 1100 or so. I don't actually pour all the spent wort from the starter into the batch, but rather, I make a 2 liter starter, let it ferment out, pour off the spent wort, add 2 liters more wort let that ferment out, pour off most of the spent wort and use that. If you answered no to either of those two questions, you can make up a new, bigger starter and pitch that. If the alcohol level is really high, then about all you can do is to pitch a more alcohol-tolerant yeast, such as Pasteur Champagne yeast, available both dry and from Wyeast. You should still make up a big starter even if you use a more alcohol-tolerant yeast. Sometimes rousing (stirring up the yeast) can lower the gravity a few more points (try to not aerate the wort too much or you will elevate diacetyl levels). If you are using a very highly flocculent yeast, such as that used by Samuel Smith's brewery, then you will have to keep rousing the yeast to get it back into suspension. Al. Return to table of contents
Date: Wed, 28 Sep 1994 15:56:55 -0400 From: Art Steinmetz <asteinm at pipeline.com> Subject: Hard Water Brewing EricT at aol.com asks about pre-treating hard water as a novice brewer. The short answer is relax. Don't bother pre-boiling. Water chemistry is very important for mashing and not very important for extract brewers, which I suspect you are. The yeast *does* care what kind of water you have but in my experiences - many batches with soft water, then I moved to a location with very hard water - I've noticed no detrimental effect over a wide variety of yeasts. When I do all grain I preboil the day before and rack off the sediment. Contamination isn't an issue since the water will be boiled again anyway. I bypass my water softener whether doing extract or all grain. I prefer calcium to sodium in my beer. Caution: when shunting the water past the softener check the taste of the water you'll be brewing with. My unit provides a salt surge when switched over. I did an all-grain O-fest I had to dump 'cuz it was saltier than a pretzel. Lesson learned. Return to table of contents
Date: Wed, 28 Sep 94 16:12:41 -0500 From: jay_weissler at il.us.swissbank.com (Jay Weissler) Subject: Pilsner Urquell Yeast Does any one have experience with the PU(D) aka wyeast w2124 yeast? Do you use a diacetyl rest? What temps do you use? Miller suggests using w2308 without the rest for a PU clone. Anyone ever try this? I've always used it with the rest for Dortmunder style lagers and have been pretty happy, but have never tried a PU. I've also been pointed at W2278. Has anyone tried this for a PU, what about the diacetyl rest, etc? TIA jayw Return to table of contents
Date: Wed, 28 Sep 94 18:28:10 EDT From: BrewerBob at aol.com Subject: Brewpubs in CA Subject: California Brewpubs I have visited By request, the following is a brief review of the brewpubs my wife and I visited during our recent trip to California. 20 Tanks Brewing, San Francisco: At least six different beers made by 20 Tanks were available. We tried: Heifer Weisen - an unfiltered wheat beer. Good but not great. Kinnikinick Stout - Light flavor, not dry but not sweet either. Kolsch, the specialty beer of the month - a mild but very hoppy beer, very good, the best of the three we tried. The service was non-existent on a Sunday afternoon. We had to go to the bar to order and a different place to order food. The atmosphere is casual with too loud rock music during a time that appeared to be an easy crowd that just wanted to talk or read. The place did not give me a feeling of cleanliness but I wasn't uncomfortable with it either. They would not give me samples, even at a price. Marin Brewing Co, Larkspur: Far and above, one of the nicest brewpubs I have been in anywhere. Clean, bright, friendly with excellent service and wonderful food, albeit mostly sandwiches and salads. I wanted a porter and a blueberry but they were out of both! We did try: Amber - very good flavor and body, an all round good beer. Hefe Weisen - not quite as good as the amber but better than average, not quite sour enough to suit me in a weisen but still very good. Barley Wine - I'm not big on Barley Wine because it usually has too much alcohol flavor. However, this one was much like Bigfoot as opposed to Thomas Hardy or Samislaus and I enjoyed it. My wife did not like it. Stout - Low bittering with nice roasty chocolate flavor, a bit too sweet for my palate but my wife enjoyed it very much. Napa Valley Brewing Co, Calistoga: Located in the back of the Calistoga Inn and Restaurant, this is a very small brewery brewing only 350 barrels a year. They have three beers which are also available in the local stores. The restaurant is tops. We had a wonderful dinner in the garden (weather was perfect). Wheat - average, not bad but not great. Amber - better than average, I enjoyed this beer enough to buy a bottle before leaving town. However, at the restaurant, the cost for a 22 oz bottle is $4.75. I got it three blocks up the street at a little specialty food store for $2.99! Sudwerks in Davis: Big, clean, modern but still a lot of bright polished wood. Good atmosphere, good service. We did not eat here but the menu looked good. Mostly lagers, only one ale available. Amber - hoppy and full bodied, tastes a LOT like Pete's Wicked Ale. This brewery is in the process of expanding from an annual capacity of 4500 barrels a year to 40,000 barrels a year! There is a very large building being built behind/beside the present building. We did not get to San Francisco Brewing Company as we had planned. We decided it would be "proper" to have lunch in Chinatown (NOT!) and did not go to the brewpub only two blocks away. Some folks said it was not very good but I'm sure it could not have been worse than the Golden Dragon! Also in the plan was to finish the trip at Pacific Coast Brewing but we got to Oakland later than we expected and we could not find a parking place. The brewery is very near to downtown (is downtown, really) and difficult to find parking on Friday evening. I heard good things about it and I'm sorry we missed it. I was a bit surprised at the lack of darker beers but I guess that shows the California preference. I personally love a good porter but I didn't have any the entire trip except for a bottle of Anchor Porter that I had with my dinner at a place on Fisherman's wharf. Also, Buffalo Bill's was listed as a "stay away" place. I read in the Celebrator that Bill has sold the place so it may improve in the near future. If you have been there and were dis-pleased, wait a month or so and give it another try. BrewerBob at aol.com Return to table of contents
End of HOMEBREW Digest #1540, 09/30/94