HOMEBREW Digest #1644 Mon 30 January 1995

Digest #1643 Digest #1645


	FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
		Rob Gardner, Digest Janitor


Contents:
  Misconceptions: cask ales. (Jim Cave)
  Stuck lautering with oatmeal (Dr. David C. Harsh)
  Re:  New revision of Suds (PatrickM50)
  Philly HB supply stores (M_MACADAMS)
  Grant's spiced ale (Marla Korchmar)
  Problem with second brew. ("Andy....pbx 5152")
  south FL watering holes (Alvin Little)
  Ascorbic Acid (Ifor Williams)
  Re: Middle Ages Water ("nancy e. renner")
  Philly homebrew shop (Mark Kempisty - 957-8365)
  RE:Stout Subs, Cornies, et al (PGBABCOCK)
  Scaling Bitterness Efficiency (kr_roberson)
  Homebrew books (Gordon Dutrisac)
  GABF/Denver Tour (Terry Terfinko)
  DC Pilsner malt in PU clones ("Lee A. Menegoni")
  Yeast Culturing/Redox Stain/Diacetyl Measurement ("Fleming, Kirk R., Capt")
  More on pH Meters (A.J. deLange)
  Re: all grain-taking the plunge (Dion Hollenbeck)
  Re: where to get cheap/good 5 gallon popkegs (Dion Hollenbeck)
  stout substitutes ("Jeff M. Michalski, MD")
  Huntsville Area Brew Clubs (David Campbell)
  beer (Isabel Kazimierczuk)
  Cheers & Salutes ("MATTHEW F. BAYLEY")
  PU Clone yeast (Martin Wilde)
  Kraustening (Chris Strickland)
  High gravity brewing? (KBONNEMA)
  Source for CAMRA Book (mpeacock)
  Roller mill speed (Jack Schmidling)

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---------------------------------------------------------------------- Date: Fri, 27 Jan 1995 5:59:47 -0800 (PST) From: Jim Cave <CAVE at PSC.ORG> Subject: Misconceptions: cask ales. There are a few misconceptions mentioned in the net about cask ale. The first is that it is filtered. To my knowledge, this is not done in the UK. However, they do centrifuge to remove most of the yeast prior to casking. The second is that it is acceptable to have slightly cloudy cask ale. This is unacceptable in England. I have had somewhat variable pints of cask ale, but _none_ were cloudy. All were brilliantly clear. I think this is largely due to the quality of the finings available there, i.e. quality Issinglass, which, when properly used, will clear a cask in only a day or so. While fiddling around with cask ales at home, I am amazed at how the flavour changes from slightly cloudy (rough, green taste) to brilliant (balance, fine taste). If the cask is disturbed, the rough taste returns. I have been very unhappy with the North American cask ales that I have had as none (that I had) were brilliant and most were too cold. Finally, there is a misconception that cask ales need to be dispensed with a hand pump. This is unnecessary, and the more traditional means of dispense is by gravity and is still practiced in a few English pubs. The cask is simply put on the stillage and dispensed through a tab that resembles nothing more than a water faucet. This can be emulated very nicely with a cobra head, 6-12 inch line and a horizontal soda keg. A gently blanket dispense is all that is required for CO2 (not as traditional as some may like, but it keeps the beer in better shape for longer). Jim (enjoying 4 cask ales very much thank you) Cave Return to table of contents
Date: Fri, 27 Jan 1995 09:15:24 -0500 From: dharsh at alpha.che.uc.edu (Dr. David C. Harsh) Subject: Stuck lautering with oatmeal Kirk Harralson wrote in #1642: > blah blah blah...There was a follow up > post about oatmeal causing stuck or difficult sparges. Does anyone > have any words of wisdom on avoiding this, or just not worrying about > it? I have heard of using rice hulls to avoid stuck sparges in wheat > beers, but have seen little regarding oatmeal. This has happened to me, but not in the classic description of a "stuck" lautering process. I made an oatmeal stout using Steel Cut Oats. These are readily available in health food stores and are pieces approximately the size of the opening in the Listermann Lauter-tun. You guessed it, the oats stuck very nicely in every opening and I spent hours trying to get any runoff and ended up dumping the batch because it wouldn't lauter, even with threats and the occasional profanity. (Later I figured out that I had screwed up the mash temperature and pH too, but that's another story.) How to avoid it? Well, I made the same recipe last fall and got a couple of small grain bags and put the oats in the bags for the mash and lautering. The recipe was the Oatmeal Cream Stout from Cat's Meow II and I've been quite pleased with the result. No problems whatsoever with the entire process. My opinion is worth what you are paying for it. Dave ***************************************************************** * Dr. David C. Harsh * * Laboratory Manager/Instructional Specialist * * Department of Chemical Engineering * * University of Cincinnati * * Cincinnati, OH 45221-0171 * * * * "I'm sick and tired of people who want something for nothing. * * But enough about undergraduates... * ***************************************************************** Return to table of contents
Date: Fri, 27 Jan 1995 09:38:49 -0500 From: PatrickM50 at aol.com Subject: Re: New revision of Suds In HBD #1641 Chuck E. Mryglot writes: <<<<< "I suspect that the (SUDS)3.1 IBU calculation is based on the much debated formula recently published in Mark Garetz's book. eg. At rev 3.0c, a recipe has a calculated IBU of 28. the same recipe in 3.1 will show an IBU of 18..... quite a difference. " . . . "I checked out BRF and it tends to agree with the 3.0c formula. Anyone know what the new and old formulas for IBU calculations are?" >>>>> When I questioned SUDS author Michael Taylor re: the new low hop calc algorithm, he said it did indeed come from Mark Garetz's research. But I also believe it doesn't agree with anything I have made before nor read about elsewhere. I have not read Mark's book so I *may* be way out of line here, but the SUDS 3.0 results are much closer to BRF software, Byron Burch's book (Brewing Quality Beers), Brewing Techniques Magazine articles, award winning AHA recipes published in Zymurgy and the Brewer's Calculator software. Maybe if enough of us emailed Michael at 76625.2552 at compuserve.com and asked him ever so politely to give us the choice of two different hop calcs in his next rev of the program he might be inclined to do so? Just a thought . . . Return to table of contents
Date: Fri, 27 Jan 1995 09:27:30 -0500 From: M_MACADAMS at Mail.Co.Chester.PA.US Subject: Philly HB supply stores Rick, There are quite a few HB supply stores in the Philly area. In center city I believe there is an "American U-Brew" place (I've been hearing radio commercials for it lately), there is also a shop in Montgomeryville. In addition, look for a new shop to open soon in the Newtown area. If you need further details, drop me a line. ? ? ?? Mike ? ? ? ? ? ? ?????? If beer ferments in the woods, and nobody ? ?? ? ?? is there to drink it..... ? ?? ? ?? ?? ?? ????? Return to table of contents
Date: Fri, 27 Jan 1995 10:00:55 -0500 From: Marla Korchmar <marlak at pipeline.com> Subject: Grant's spiced ale Does anyone have a recipe approximating Grant's Spiced Ale? Return to table of contents
Date: Fri, 27 Jan 1995 10:55:11 EST From: "Andy....pbx 5152" <copea at kenyon.edu> Subject: Problem with second brew. Hello everybody, I'm a very new homebrewer. I'm currently working on my second batch and have run into a problem that maybe somebody can help me with. My first batch of amber ale turned out very well and I decided to try a pale ale recipe suggested by a brew store I visited. Here's what I did. (steralized everything with extreme care, using Super-Clor, a chlorine based cleaner. Soaked all things for half-hour and then rinsed thoroughly twice.) Boiled two gallons of bottled water. Added two cans of Munton Light Malt extract. Added 1 and 1/2 oz. of Northern Brewer flower hops -Boiled for one hour -Removed from heat Added 1/2 pound of crystal malt Added 1 and 1/3 oz Tettenang (sp?) hops -I allowed this mixture to steep for 10-15 mins. -I then moved immersed the pot into a cold-water sink. -When the water would become warm I would drain and add more cold in. -It cooled much more quickly then I expected, went down to about 65 degrees. I poured the wort into my plastic primary through a strainer to catch the hops and undissolved crystal malt. I then added three more gallons of cool water. This brought the temp lower than I wanted (I don't remember the exact level I measured.) -I then added one package of EDME dried yeast. This is all I know about this yeast, as I'm new and hope that the name rings a bell. -I sealed it and attached the airlock. The problem is this. After four days, I've had virtually no activity from the yeast. There was some tiny bubbles at first and for about one day, the water in the airlock was being pushed (I've got a "S" shaped airlock). After that day it hasn't moved at all. Yesterday I took a peek and although it smelled very nice indeed, I could see yeast still floating on the top (At least that's what it looked like). I thought that perhaps I added the yeast when the wort was too cold but I thought that as the liquid moved closer to room temp (68-70 degrees) it would activate. Was I wrong about this? I moved the primary to a warmer portion of my home and in 24 hours there's still been no activity. What should I do? Is it hopeless? Should I just toss the stuff and start again? If you have any words of wisdom, feel free to e-mail me privately. I'd be happy to post a summary to the digest so that any other new brewers can benefit from the responses. Thank you for your time. Andrew Cope Return to table of contents
Date: Fri, 27 Jan 1995 11:23:25 -0500 From: little at charlotte.med.nyu.edu (Alvin Little) Subject: south FL watering holes From: Skip little at charlotte.med.nyu.edu Subject: Brewpubs, pubs in S. FL I'll be visiting South Miami Beach and the Keys, in a month and would appreciate any info on pubs with good beer selections or brew pubs in that area. Responses by private e-mail are welcome. Slainte. Return to table of contents
Date: 27 Jan 95 11:30:47 EST From: Ifor Williams <100140.2651 at compuserve.com> Subject: Ascorbic Acid I was reading an item in the Winter Zymurgy about bottle caps that reduce oxidation of beer and was wondering why not add anti-oxidants to the beer instead? Would a dose of Vitamin C achieve the same effect? If so, how much? Could this have a negative effect on the beer? Does anybody have any experience/comments? Cheers, Ifor. Return to table of contents
Date: Fri, 27 Jan 1995 11:37:19 -0500 (EST) From: "nancy e. renner" <nerenner at umich.edu> Subject: Re: Middle Ages Water (From *Jeff* Renner) In HBD 1642, Mark Witherspoon said >Subject: Middle ages water. > >The reason bear and wine were the things to drink then and now >was the pollution of the local water supply. The water over >there then was full of bacteria (typhus, ameboa, step,staff, >etc..). Sorry, Mark. I'm not picking on you, but there are some problems here (I checked my facts on these critters in the World Book Encyclopedia, 1988, articles on each). "typhus" - Nope, typhoid. Typhus rickettsia are transmitted by lice, fleas, ticks or mites. Typhoid, which means "typhus-like," is water borne, and was indeed, and still is in much of the world, a great problem. "ameboa" - Ameba are protozoa, not bacteria, but you are right, while most are harmless, one kind causes amebic dysentery, a serious water borne disease. "step" - Streptococci are generally air borne in moisture droplets sprayed from nose or mouth. "staff" - Staphylococci are indeed found everywhere, including in water. They can cause food poisoning, but not the bacteria themselves. The toxins they produce cause the disease, and these are produced in contaminated food, not in water. >The boiling of the wort and the fermenting (alchol >creation) would destroy all or most of the bacteria content. True enough, but boiling was not a universal part of brewing. Some authors even claimed that boiling made unhealthful beer! (I can't give you the source for this - I read it years ago in several brewing histories). More important is/was the low pH of the beer. Beer in those days was probably more like lambic. It was difficult to avoid acid producing lactobacillus infections that dropped the pH even further than in modern beers, preventing the growth of pathogens. >Now days the local water is so full of heavy metals that >boiling will cause most of them to drop out or be absorbed by >the grain, protein, and yeast. Whoa! Several problems here. What local water? There are strict federal regulations (which can be superseded by even more stringent state requirements). (These are examples of "unfunded federal mandates). Lead and copper are mostly a problem in distribution (where water stands in lead or copper pipes, especially with lead solder. The limits are 15 micrograms/l Pb and 1.3 mg/l Cu in the 90% highest risk households. Ann Arbor, for example, easily meets these. Other limits: arsenic - 0.05g mg/l (AA, 0.0004); cadmium - .005 mg/l (AA, none detected at 0.001 limit); chromium - 0.1 mg/l (AA n.d. at 0.001); selenium - 0.05 mg/l (AA n.d. at 0.005). (Thanks to AA Water Treatment water quality manager for these numbers, no affiliation etc., not even a satisfied customer any more since I'm now on well water). I don't think your statement can be justified, at least as a general indictment of municipal water. I also don't know how boiling would remove heavy metals, and wonder what mechanism you propose for their absorption by grain, protein and yeast. I'm sorry that this may look like a flame. It isn't intended as one, but rather a correction that must be made publically since the claims were public. I hope I was gentle. Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu Return to table of contents
Date: Fri, 27 Jan 1995 11:58:38 -0500 (EST) From: Mark Kempisty - 957-8365 <MKEMPISTY at gic.gi.com> Subject: Philly homebrew shop In HBD #1640 Rick Gontarek asked if there were any homebrew shopy in the Northeast section of Philadelphia. Though not in Northeast Philly, Homebrewers Outlet in Fairless Hills near the Oxford Valley Mall shouldn't be too far. Though the store is small (10 X 15 feet sub-leased from a beer distributer) he has everything you might need. And if it isn't in stock he will gladly order it for you. Prices are average. You can call your order in ahead of time and pick up. Finally, if you want to talk beer and brewing you can spend hours doing it with him or his significant other. He has had to cut back on some of the shop's hours because of twins but is open evenings and all day Saturday. If you want to know their phone number and address, let me know via E-mail and I will send them to you. And now the usual stupid disclaimer... I have no interest in his business venture. Just an extremely satisfied customer. - -- Mark mkempisty at gic.gi.com) Return to table of contents
Date: Fri, 27 Jan 1995 11:56:23 -0500 From: PGBABCOCK at aol.com Subject: RE:Stout Subs, Cornies, et al This is a REAL long one, so please bear with me.... In HBD #1642: -=> M.Marshburn asks about roasting his own specialty barley malts, and whether to use wheat flour in place of wheat grains... Dave Miller treats the subject of home roasting malts in his Handbook of Hombrewing (or whatever. Far too many 'Handbook' titles out there to keep track of <G>). I've tried his method with good success. As far as using the flour goes: You can do it, but I wouldn't want to be running that sparge! Mashing flours yields more (usually) than mashing cracked grains, so you may want to use less. I can't tell you how to avoid the sparge-sticking you're in for... -=>Wade Wallinger expounds on his kegging experiences and asks for others... Process 1: Pressure test... I use a squirt bottle filled a solution of about an ounce of dish soap to about 4 ozs. H2O. I spray down all the fittings, the bung, and the seam (where exposed). I pressurize to 20 lbs (no ramp-up), and hunt for bubbles. I then rinse all the soap off before proceding. Pressure is more easily released by lifting the pressure relief lever or ring (if so equipped) than by either of the fittings. One thing I noticed is that, on most of my kegs, the bung cover goes on in only one direction without leaks. I've numbered the kegs and cover, and marked each keg and it's cover to ensure the same match and direction each time (used a cheap engraver). Your overnight test is an excellent idea for new or questionable kegs, though. I've a few I'll try this on... Process 2: Sanitize the keg Many will argue, but: not only CAN chlorine attack SS, it WILL at every opportunity! And, the effects are cumulative. Even chlorinated tap water is contributing to some degree. I recommend NOT using any chlorine compounds to sanitize SS. SS ceiling structures over indoor pools have been embrittled by airborne chlorine from the pool over time. I would imagine the airborne concentration is much less than that used for sanitation (not an expert). I recommend Iodophur (sp) or other non-chlorine sanitizers. Many will argue again, but rinsing may counter any sanitizing done. Personally, I DO rinse - but I get current (monthly) water analysis reports from the city and monitor THM levels and organics. I also filter with activated charcoal (whole house system) and crank my water heater up prior to any of these activities. I guess my recommendation here is to rinse only if you know your water. Otherwise, use solutions/concentrations that allow rinse-free sanitation. Process 4: Filling Prior to racking the beer to your keg, allow CO2 to run in with the bung open. This displaces air in the keg, protecting beer from oxidation (CO2 is heavier than air). I bought an extra outlet fitting which I have attached to the other end of my racking hose. This allows me to rack my brew from the bottom of the carboy or priming bucket to the bottom of the keg - ie. no splashing! I then fit the bung cover (after removing the racking fitting) and pressurize the keg with 5 psi or so to seal it before I throw the bung bail. Additional goodies on the subject: To cool your beer without a fridge, get the following: 15 - 20' x 1/4"OD copper or SS tubing 6' x 1/4" ID food grade vinyl hose 1 Cornelius Outlet fitting 1 Picnic Spigot 4 small diameter hose clamps Extra 5 gal bucket Coil the copper around the bottom of your keg (Just using the keg as a form here...). Attach 3' of hose to each end of the copper and clamp in place. Attach Cornie outlet fitting to one end and spigot to the other. Clamp in place. Sanitize the assembly. Drop the coil in the bucket, fill the bucket with ice, attach to keg, and dispense cold beer. This device is commonly referred to as a 'Jockey-box'. As an alternative, you can build the coil into a cooler (steel cooler recommended) and attach a bar-style beer faucet to it. Great for picnics! -=> Dave Housman expresses his opinion about the cost of Irish Moss (Carrageenan)... Irish moss CAN be had cheaply; however, I've seen homebrew supply shops charging as much $1.99 for 1/4 oz of this stuff. Being most of us buy from local shops, we pay the high price. I feel for Jim; I agree with Dave... It's all about choices. -=> Dave Ebert asks for opinions about allowing the wort to stand for 24 hrs prior to pitching... IMHO, some of the break material that settles out in that preliminary 'rest' would be 'kicked back into suspension' by the CO2 evolving from the busily fermenting yeast (without the preliminary rest). By the same token, the majority of re-suspended material could be settled out with a rest in the secondary following fermentation. At this time, there is little or no CO2 bei ng generated - (bubbling here is usually due to out-gassing of suspended/dissolved CO2). To make a short story even longer, it should improve the clarity of the finished beer. Depending on your 'normal' practices, this could be a vast, noticeable improvement, or negligible. BTW, if you can cool the beer during this rest (spare refrigerator), you may even settle out some chill haze constituents... -=>Bill Perry asks about reasonably-priced Cornie's. The most reasonable I've found in mail order was from Maltose Express (1-800-MALTOSE). I don't recall the price off-hand (call for their catalog. Includes useful profiles on yeast!!!), but I know they had both 5 and 3 gallon at the same price (between 30 and 45 as I recall). Also had good prices on regulators, tanks, etc... (BTW: I'm not affiliated with them or any other supplier.) -=>Darn! I had a question, but after all that I've forgotten what it was... ;-) "Beer is life! (The rest is just details...)" Brew On! Pat Babcock President, Chief Taste-Tester, and Consumer Numero Uno Drinkur Purdee Pico Brewery pgbabcock at aol.com brewbeerd at aol.com Return to table of contents
Date: Fri, 27 Jan 1995 09:38 -0800 (PST) From: kr_roberson at ccmail.pnl.gov Subject: Scaling Bitterness Efficiency Greetings from the confluence of the Columbia, Yakima and Snake rivers, I was wondering if anyone had any data on how the hop utilization factors might scale with batch size. I've been using the common chart that tops out with 30% after 60 minutes (at low gravity). There is a correction for density, but not for batch size. I make 6 gal. batches now and I know things will change as I move up to 1bbl to 7 bbls. Changes in extraction efficiency I think I can handle by checking the gravity (although tips on how this might scale would be gratefully accepted) and timing the boil, but how IBUs will change is harder (I think). I would expect that I would need to start off low and extend the boil until it tasted "right". However, my bitter wort taster is not as well calibrated as my finished beer taster! Let me know if this is treated in the archives somewhere, Kyle Return to table of contents
Date: Fri, 27 Jan 1995 14:22:44 -0400 From: Gordon Dutrisac <ac075 at cfn.cs.dal.ca> Subject: Homebrew books My roommate and I recently purchased a homebrew kit and are really interested in learning all we can about kit and scratch brewing. Could anybody suggest good comprehensive books on the topic. thanks for your help, Gordon Dutrisac Halifax, N.S. Return to table of contents
Date: Fri, 27 Jan 95 13:33:04 EST From: terfintt at ttown.apci.com.apci.com (Terry Terfinko) Subject: GABF/Denver Tour I am planning a trip this October to the Great American Beer Fest in Denver. I plan to spend a week in the Denver area and would appreciate any information on breweries/brew pubs to visit. Also any advice on hotels in close proximity to the convention center were the beer fest is held would be helpful. Terry Terfinko - terfintt at ttown.apci.com Return to table of contents
Date: Fri, 27 Jan 95 13:39:50 EST From: "Lee A. Menegoni" <lmenegoni at nectech.com> Subject: DC Pilsner malt in PU clones In my post on Brewing a PU clone I mentioned that the German Pils malts from Durst and Ireks were superior based on prior posted info. That ifo was from George Fix, In one of the first issues of Brewing Techniques he reviewed the DC malts. He mentioned that the Plis was a highly modified malt and that it was low in, SMM, a sulphur compond which contributes to malty flavor and aroma. In a more recent post to HBD Doctor Fix mentions that the type of grain used for the Pils malt had changed, d that it had high nitrogen and other chacteristics and these made it a lower quality malt than the original DC Pils. In another post Fix mentions that the degree of modification of continental malts like Durst and Ireks had increased, he still felt that they should be protein rested. Going from memory now, I believe he described them as "less modified" malts putting them between under modified and highly modified. Lee Return to table of contents
Date: Fri, 27 Jan 95 11:03:00 MST From: "Fleming, Kirk R., Capt" <FLEMINGKR at afmcfafb.fafb.af.mil> Subject: Yeast Culturing/Redox Stain/Diacetyl Measurement RE: The Practical Brewer (Chapter XI, Yeast-Stains and Handling Techniques) See p. 203 para. 2, referring to respiratory-deficient mutants (petites): "Since they do not posess oxidative properties, their colonies can be easily distinguised on agar plates by adding a redox stain, e.g., tri-phenyltetrazolium chloride. [TPC]" Based on a description of TPC in my reagent catalog, it is mixed in with the agar (or other) culture medium when preparing plates or slants. My question for you yeast farmers is: have any of you used TPC for RD mutant detection, and if so, how much do you use in the medium? I haven't done any culturing--I guess there is no reason to expect any mutants on a slant prepared from a lab culture yeast, but I'm thinking the occassional use of TPC would provide an entertaining spot check for slants that had been sub-cultured over many generations or maybe cultured from beer wort populations. Kirk R Fleming -flemingkr at afmcfafb.fafb.af.mil -BEER: It's not just for breakfast anymore. Return to table of contents
Date: Fri, 27 Jan 1995 14:24:29 +0500 From: ajdel at interramp.com (A.J. deLange) Subject: More on pH Meters The following long post was generated as a letter to the editors in response to Dave Miller's column in the last Brewing Techniques but answers some questions I received from my last post on the subject of pH meters here. In measuring the pH of wort there are two effects involved both of which need to be accounted for. First, the true pH of wort varies with temperature. Wort is acidic (pH less than 7). This means that organic acids (in particular phytic acid) are present and are disassociated. Disassociation is a process in which the acid molecule gives up one or more protons (hydrogen ions). The pH is proportional to the negative logarithm of the hydrogen ion concentration so that the more disassociation which takes place the lower the pH (no wonder it's confusing). Unsurprisingly the degree of disassociation is a function of the temperature and increases as wort temperature rises. Thus a particular wort is more acidic and has a lower pH (by typically 0.35 pH) when it is hot (65C) than when it is cool (18C). Second, the pH electrode is in reality a very feeble battery whose terminal voltage depends upon the pH (hydrogen ion concentration) of the wort and the temperature except at pH 7. At this pH an ideal glass electrode produces 0 millivolts (mV) at any temperature. At 25 C an ideal glass electrode would produce +59.17 mV for each unit of pH less than 7 (e.g. 118.34 mV for pH 5). The mV per pH unit is directly proportional to the absolute temperature (obtained by adding the centigrade temperature to 273.16) of the solution. Thus, in general, the ideal electrode produces a voltage V = 59.17(7 - pH)(T + 273.16)/(25 + 273.16) mV where T is the temperature of the solution (wort) in degrees C. The foregoing means that if a perfect buffer (true pH constant with temperature) is measured with an uncompensated meter the pH reading will depend upon the temperature. With respect to the first issue; the brewer who wishes to benefit from guidance like: "An infusion mash is best carried out at pH 5.2 - 5.4." [Briggs, Hough, Stevens and Young, Malting and Brewing Science, Vol I p279] must know the temperature at which the pH was specified. The sentence in this reference which follows the one just quoted says "Consequently the pH in the cooled wort will be 5.5 - 5.8 [at 18C]" so it is quite clear that these authors are specifying the pH at the temperatue of the mash. Conversely, DeClerk [A Textbook of Brewing, Vol 1 p267] says "When pH is mentioned in connection with mashing, it always refers to the cooled wort" but then on the next page: "...for a correct appraisal of the situation the pH should be measured at the temperature of the reaction." If the brewer ignores this last bit of advice or is compelled to measure cool wort because his meter won't withstand the temperatures of the mash then he must correct the reading to the temperature at which he wishes to know the pH if it is different from the one at which he took the measurement. As indicated above this correction amounts to an average of 0.35 pH units (the correction varies somewhat according to the composition of the grist and the liquor) to be added to a reading made at 65C to get the value at 18 C or subtracted from a reading at 18C to get the value at 65 C. I repeat for emphasis that this is not a correction for the electrical response of the meter electrode to temperature which correction is assumed to have made before this correction is applied. With respect to the second issue; there is no such thing as an ideal glass electrode and even if there were ideal performance would not be acheived because of imperfections in the meter which measures its voltage. This means that a real electrode does not give 0 mV at pH 7 nor does its output change by 59.17 mV per pH unit at 25C. Buffers (solutions with known pH) and calibration via controls or computation are used to overcome the basic limitations of the instrument. Success depends upon the degree to which the voltage produced is a linear function of the pH and the absolute temperature. There can be from 0 to 3 calibration controls on a pH meter. One is the offset or zero control. To use it one places the electrode in pH 7 buffer and adjusts the control until the meter reads pH 7 (or 0 mV on meters which also have a millivolt scale). The second control is the "span" control which adjusts the meter so that it reads the pH of a second buffer (pH 4 for brewing applications) correctly. If the third control is present it is the temperature compensation control and should be set to the buffer temperature when buffer readings are made and to the wort temperature when wort readings are made. Automatic meters don't have controls. They are simply millivolt meters with a microcomputer and a display. Let us pretend that one of these meters as its first processing step converts every millivolt reading to pH by dividing by 61 and subtracting from 7. This is exactly what a cheap pH meter i.e. one with no controls does: convert millivolts to pH. The 61 mV/pH is the theoretical sensitivity at 34C so that such a meter is "calibrated" in terms of span at that temperature i.e. the pH reading would change by 1 for every unit of true pH change in a wort at 34C. Now let us list the steps that the microprocessor in an ATC meter would go through to measure and display a corrected (for span, offset and temperature) pH reading. A brewer can correct readings from a cheap meter using these same steps. To illustrate the correction algorithm let's further suppose that the meter has an offset of +12 mV so that it reads 7 - 12/61 = 6.80 when the electrode is in pH 7 buffer and give numerical values (in brackets) with each step for a situation where a wort at pH 5.00 at 65C is to be measured. We will assume that the buffers are at 20C. a. Read the temperature of the buffers and store in memory. [Example: 20C]. b. With the electrode in the pH 7 buffer, take and store the pH reading. [Example: 6.80] c. With the electrode in the pH 4 buffer, take and store the pH reading. [Example: 3.94] d. Compute the span at the buffer temperature by differencing the buffer readings [Example 6.80 - 3.94 = 2.86 ] f. Read the temperature of the wort. [Example 65C] g. Compute the span at the wort temperature: (new span) = (buffer span)(wort temp + 273)/(buffer temp + 273) [ Example 2.86(65 + 273)/(20 + 273) = 3.30 ] h. With the electrode in the wort take and store the pH reading. [Example 4.60] i. Subtract the wort pH reading from the pH 7 buffer reading. [Example 6.80 - 4.60 = 2.20] j. Divide by the new span. [Example 2.20/3.30 = 0.667] k. Multiply by 3 (the difference in the true buffer pHs). [Example (3)(0.667) = 2.00] l. Subtract this from 7. [Example 7 - 2.00 = 5.00] If the meter has any controls one may use them or not as desired. Adjust a zero control to read 7.00 in the pH 7 buffer. Adjust a span control (after adjusting the 0 control) to read 4.00 in the pH 4 buffer. The correction procedure is unchanged. Finally I'd like to raise a cautionary note concerning the sticking of electrodes into the mash tun. One of the most popular pH meter references is the calomel half cell. Calomel is mercuric chloride and it starts to decompose at around 140 F. If one were to place such an electrode into hot mash one would, at best, destroy the electrode and at worst (although you very probably won't) get mercuric ions into the beer. Before placing an electrode into the mash the brewer must know the composition of the electrode, that it will withstand the temperatures involved and that the fill solution, some of which will pass into the mash, is innocuous. If uncertain, withdraw a sample for testing and discard it. A.J. deLange ajdel at interramp.com A.J._deLange at csgi.com Return to table of contents
Date: Fri, 27 Jan 95 11:28:29 PST From: hollen at megatek.com (Dion Hollenbeck) Subject: Re: all grain-taking the plunge >>>>> "ray" == ray fugitt <rfugitt at ix.netcom.com> writes: ray> I am ready to take the plunge, I'm looking for suggestions on a all ray> grain system. I am looking to buy one, not make it. The biggest ray> limitation is I live in an apartment, not alot of room. I am interested ray> in a system that has it's own heating source if possible, my stove does ray> not heat up well. Dealers replies welcome. ray> rfugitt at ix.netcom.com You may want to investigate a RIMS system due to the fact that it heats the mash with an electric element. The boil can be done with a propane burner camp stove. However, they are very expensive to construct. Look in the 1992 Zymurgy Special Issue for an article by Rodney Morris on RIMS construction. After reading it, ask me any questions you desire. I am an expert. dion - -- Dion Hollenbeck (619)675-4000x2814 Email: hollen at megatek.com Staff Software Engineer Megatek Corporation, San Diego, California Return to table of contents
Date: Fri, 27 Jan 95 11:36:51 PST From: hollen at megatek.com (Dion Hollenbeck) Subject: Re: where to get cheap/good 5 gallon popkegs >>>>> "William" == William Perry <William.L.Perry.13 at nd.edu> writes: Bill> Sorry to post here and not on the news group, but our news Bill> server is having its midlife crisis right now and has decided Bill> not to accept postings for some odd reason. Anyway, I am Bill> interested in purchasing or finding 5 gallon pop kegs. I have Bill> tried all of the bottlers in south Bend, Indiana (no laughing Bill> please) and they were not helpful at all. If anyone has Bill> suggestions on where I might get them relatively cheap I would Bill> appreciate it. The cheaper the better according to my wife. I Bill> would be interested in buying 4 or so for all of the different Bill> brews. Thank you very much, Bill Perry First try looking in Zymurgy for ads. They will be more expensive than the second option, but have generally been pressure tested and maybe have even had the rubber O-rings replaced. Then try looking at scrap metal recycling yards. I got 12 kegs last weekend for $5 each. All of them were holding pressure and a little bit of soda syrup when I got them and they had obviously been sitting in the scrap yard a long time. Of course, they will require re-gasketing before use which is an additional expense. I had to drive 1.5 hours each way to reach this scrap yard, but for kegs I could cherry pick and were in excellent shape (no dings, dirty as hell, no leaks) it sure was worth it. Unless you are a reasonable distance from Santa Ana, CA, don't bother asking for the name of the scrap yard. They don't do mail order and I won't either. dion - -- Dion Hollenbeck (619)675-4000x2814 Email: hollen at megatek.com Staff Software Engineer Megatek Corporation, San Diego, California Return to table of contents
Date: Fri, 27 Jan 95 13:55:49 -0500 From: "Jeff M. Michalski, MD" <michalski_jm at rophys.wustl.edu> Subject: stout substitutes I tried mailing this directly but it bounced. The question was about substitutions for Barrel of Monkeys Wheat Oatmeal Stout. Mike, You are missing the key ingredients to make a stout of any type let alone the recipe that you are describing. The roasted barley in a classic dry stout is unmalted. Some varieties of stout have substituted black patent or chocolate malt for the roast but you will not have the fantastic roasty aroma that accompanies a good stout. Raw wheat (unmalted) is not an appropriate substitute for malted wheat. I would recommend that you either omit the whole wheat flour or get the real thing. The oatmeal stout substitutes the classic "flaked Barley" that is used in the making of a classic dry stout. It adds body and head retention. It has a smoother note than the barley. Some describe it as silky. To sum up, I would go through the trouble of getting the ingredients you need rather than improvise. If the ingredients weren't so critical to the style you are trying to make it would be ok but the roasted barley (and to a lesser degree the wheat malt) is very important. Try your homebrew supplier or mail order. JEFF M. MICHALSKI michalski_jm at rophys.wustl.edu Return to table of contents
Date: Fri, 27 Jan 1995 14:07:48 -0600 (CST) From: davidc at office.sirsi.com (David Campbell) Subject: Huntsville Area Brew Clubs I am fairly new to the Huntsville area, and would like to know of any home brew clubs around. Private email is fine. davidc at office.sirsi.com Return to table of contents
Date: Fri, 27 Jan 1995 14:57:44 -0700 (MST) From: Isabel Kazimierczuk <iek at GAS.UUG.Arizona.EDU> Subject: beer I'm a beer lover. Send me info on the best brewing! Isabel Return to table of contents
Date: Fri, 27 Jan 95 17:03:07 EST From: "MATTHEW F. BAYLEY" <BM#B%LAFAYACS.bitnet at lafibm.lafayette.edu> Subject: Cheers & Salutes I'm looking for a short (20 or so words) quote/cheer/saying to engrave on pewter flasks for the men (by far still boys in many people's minds) in my bridal party. Humorous, sentimental, or just plain old salutations are all welcome- especially those personal favorites. If it helps any, we've all known each other for a good 15 years, and none of us are any strangers to throwing a few back! Many Thanks! Return to table of contents
Date: Fri, 27 Jan 95 14:14:02 PST From: Martin Wilde <Martin_Wilde at ccm.jf.intel.com> Subject: PU Clone yeast Text item: Text_1 The best yeast for a Pilsener Urquell clone is from Brewers Resource. I don't remember the order name, but just ask for the PU like yeast. It gives that nice hint of buttery flavor that PU has. The yeast is reportably the same yeast as PU uses. Yes I know that PU has 3-5 strains of yeast, but I have used this yeast many, many, many times and it produces that authentic PU yeast profile. Brewers Resource can be reached at : 800-827-3983 martin Return to table of contents
Date: Fri, 27 Jan 1995 18:58:58 -0500 From: cstrick at iu.net (Chris Strickland) Subject: Kraustening Let me try one more time. I tried kraustening a batch of beer. I saved off about 40 oz of 1.062 beer. I primed with the "green" beer, based on the bottles I believe it's a slight bit overprimed (I can live with that). My major problem is that I have about 1" of crap in the bottom of the bottle now. How can I use kraustening and avoid the sediment in bottom of the bottles? Also, I was given the maltmill for a Christmas present (I was using a blender). My specific gravity has gone from the 1.044-1.052 range to the 1.058 to 1.064 range. The mill was expensive, $149 but it's been well worth it. I am now the proud owner of seven mini-kegs, I'm in love! I use three per batch of beer, and bottle between 4 and 9 bottles (depending on size of bottles). I'll never go back to all-bottling again. I've been using the mini-kegs for the last six batches or so. - -------------- Chris Strickland cstrick at iu.net Return to table of contents
Date: Fri, 27 Jan 1995 19:21:41 -0500 From: KBONNEMA at aol.com Subject: High gravity brewing? I've been browsing through many back issues of the digest and remember seeing a post about "high gravity" brewing (sorry I can't remember the issue.) I have been partial mashing for a few months now, and would like to move to all-grain, except for one problem, I don't have the equipment or facilities to do a full wort boil. My question for the HBD continum is: What are the draw backs of going to all grain receipe's but only boiling ~2 to 3 gallons of the wort, and making up the difference by adding water to the fermenter (as in extract brewing) ? It seems that other than sanitation and hop utilization concerns, that this would provide an avenue for much better brews. A post or Email would both be welcome. TIA....Kurt Return to table of contents
Date: Fri, 27 Jan 1995 17:14:07 -0600 From: mpeacock at dttus.com Subject: Source for CAMRA Book Can anyone suggest a US source for the CAMRA book "Brew Your Own Real Ale At Home"? Even some biblographic info with an ISBN would help -- with that I might be able to have Border's special order it. TIA, Mark Peacock Birmingham, Michigan Return to table of contents
Date: Fri, 27 Jan 95 21:06 CST From: arf at genesis.mcs.com (Jack Schmidling) Subject: Roller mill speed From: Tom Clifton <0002419419 at mcimail.com> >The subject has come up regarding the "correct" feed rate (as in feet per minute) for a motorized mill. This would likely effect the quality of crush as well the condition of the grain due to possible shattering or heating of the grain if crushed too rapidly. I really don't think one could establish any universal "correct feed rate" as it depends too much on the type of rollers. Within limits, the surface speed of the rollers has more effect on the mills ability to feed grain efficiently than on the quality of the grist. > Specifically this is in regard to a mill my father is making from the Chris Barnhart plans. The mill has been changed a bit by its use of 6" long X 3 5/8" diameter hard maple rollers. The key to the answer is the type of texturing used on the rollers. With none, there probably is no speed slow enough, with very coarse, you can probably go as fast as you want. The problem you will have with wood is that whatever texturing you use, it is subject to wear and it will need to be renewed on a regular basis. As reference points, the MM with 1.5" diameter rollers, is most commonly run at 400 RPM with good results. The MMII with 3" diameter rollers also runs well at the same speed and one customer ran one at twice that speed, contrary to my advice. There is a point beyond which nothing is gained but a lot of dust and noise. In a hombrew environment, I would opt for the slow end. > The drive is via an electric wheelchair motor that turns at 180rpm at 12 volts which seems awfully fast for such a diameter roller as this would result in a feed of around 180 feet per minute. Sounds like a nice loafing speed IF you have the roller textured properly. >Also of concern is the torque available from the motor. It is spec'd at 20 inch pounds when running on 24 volts with a draw of 8.4 amps. Frankly, I don't think you are even in the ball park. I found that the MM required 60 in/lb by measurement but in practice, requires several times that if one is to believe what the manufacturers claim for their motors. I bought a 60 in/lb gear motor and even geared down 2:1, it would only work if the mill was started first. That's 120 in/lb or 10 ft/lb torque. I suggest that you don't count on the "when running" condition. Phones ring and lots of other reasons come up for stopping with the hopper full. Nothing is a bigger pain than emptying the hopper and the rollers to get it started again. BTW, the rollers on both MM's are much longer than yours and this would affect both the feeding efficiency and the torque requirements. However, your larger/shorter rollers probably require as much or more torque than the standard MM. Just a final note.... I have found over the years that the only people who ever had problems motorizing MM's were the ones who used gear motors and/or hand drills to power them. You just can't beat a simple motor with pullies and a belt. js Return to table of contents
End of HOMEBREW Digest #1644, 01/30/95