HOMEBREW Digest #2375 Sat 15 March 1997

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  Re: Protein terminology (part 1) (Steve Alexander)
  Re: Protein terminology (part 2) (Steve Alexander)
  Re: decoction at mashout (korz)
  Evaluating Starters ("Kirk Harralson")
  Live Beer (Bruce Baker)
  RE:  Mashout/Partial Decoction ("Toler, Duffy L.")
  RE: Yeast pitching / chocolate beer / burnt counter tops (George De Piro)
  dry yeast storage (Jeff Sturman)
  brews for a wedding (Eugene Sonn)
  Lactoak, sour mash ("David R. Burley")
  where to buy hop plants ("FINLEY, BARRY CURTIS")
  Decoction mashing (Bill Giffin)
  Runoff Gravity Change Equation / Keg Chillers (KennyEddy)
  foamy beer (Tom Pope)
  foamy beer (Tom Pope)
  Re: Pubs in UK ("Brian M. Rezac")
  ban the sour mash (BAYEROSPACE)
  Re: decoction at mashout (John Wilkinson)
  Re: HBD Dist List Use (Dave Hensley)
  '70's Flashback -- Miller Proud of Bland Beer; Secures Patent (KennyEddy)
  re: heterofermentative bacteria (Steve Alexander)

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---------------------------------------------------------------------- Date: Thu, 13 Mar 1997 01:57:57 -0300 From: Steve Alexander <stevea at clv.mcd.mot.com> Subject: Re: Protein terminology (part 1) Harlan Bauer writes about proteins enzymes and terminology ... >What I'm trying to get a handle on is what terms refer to what weight >proteins? IOW, from the following lists, what is the correct order from >largest to smallest molecular weight? And which would go under the headings: >heavy, medium and low molecular weight proteins and the enzymes that >catalyze the reaction? (I realize these enzymes are classes of enzyme and >that there are a lot of specific enzymes represented by each class.) Let's do the easy (and first thing) first. PROTEINS: >albumin >globulin You forgot hordein and glutelin - these four names form a functional classification of proteins. Albumins are water soluable globulin is salt water soluable, hordein is soluable in warm ethanol and glutelin isn't soluable in the above. Hordein is a plant store of amino acids - the amount of hordein falls and the amount other peptides rises throughout malting. >"true" proteins excluding non-amino nitrogen and simple amino acids as well as excluding proteins compounded with lipids and sugars. BTW - cell walls are full of peptoglycans and peptolipids [thanks to Jeff Renner for pointing out the difference between cell walls and cell membranes re yeast - I wasn't making the proper distinction in a previous post.] >albumose Don't know ?? Peptone is the one that doesn't quite fit. A lot of culture media for microorganisms list peptone as an ingredient. Peptone is a degraded beef muscle tissue, which includes a lot of proteins and amino acids but isn't well characterized. but ... >proteose >peptone Proteose and peptone are also used to denote the non-amino acid nitrogen containing fraction of an Osborne degradation of protein according to M&BS. The fact that they represent non-amino nitrogen is sufficient for my purposes. I'd look up the Osbourne degradation for more detail. >peptide Peptide - an amino acid polymer in which the individual amino acid residues are linked by amide bonds. Amide - compound containing the -CONR functional group. (R represents a radical that indivuates the particular amino acid) O || R-C--NH2 Amide Amide bond - links amides, as in the dipeptide ... O O || || NH2-CH-C--HN-CH-COH | | R' R'' Polypeptide - generally refers to peptides smaller than proteins. Sometimes referenced as 2 to 30 amino acids linked. Protein - a large peptide containing 50 or more amino acid residues. ENZYMES: Common Names - The naming of enzymes is a confusing thing. Common names for enzymes are based in all sorts of things tho' often because of a natural source: Alpha-amylase is also spitase because of its presence in saliva, Beta-amylase goes by maltase because of its presence in malt, Proteases papain and ficinase because of their presence in papaya and figs. Common names for enzymes are also taken from their substrate, their product and their common uses. I have a list of 23 common names for alpha-amylase! With a given field of use, common names often make useful handles for communication purposes. If we were all discussing the George Fix 40-60-70 mash schedule we might coin names like '40ases' and '60ases' to refer to the enzymes active at the various temperature steps. Common names are, by themselves, uninformative. Common names for enzymes aren't cast in stone - make up a name if it suits your purpose. Everyone else does. Systematic Names - There are 6 broad classes of enzymes: hydrolases, isomerases, ligases, lyases, oxidoreductases and transferases. Within the 6 broad classes above there are subclasses, for example under the class of hydrolases (which break bonds by hydrolysis) there are amylases, lipases, nucleases and proteases among others. These subclasses can be further dissected. The systematic names for enzymes have two parts, the first part defines the substrate, the material or specific chemical bond on which they act, and the second part defines the enzyme class (above) with an '-ase' suffix. Thus beta-amylase is systematically name '1-4-alpha-D-glucan maltohydrolase, while alpha-amylase is '1-4-alpha-D-glucan glucanohydrolase'. 'beta-amylase' and 'alpha-amylase' are listed as the 'recommended' names. EC classification - Sometime in the 1950's, when the discovery rate of new enzymes was skyrocketing, an international committee was formed to classify the nomenclature (naming) of enzymes. In addition to the systematic naming convention an EC (Enzyme Committee) numerical classification was created. Beta-amylase is thus EC, and alpha-amylase is EC The initial 3 refers to the hydrolases, the 2 in the second position is for glucanases, the 1 indicates a sub-sub category that is subclass specific and the final 1 & 2 are for the specific enzyme modality - it's method of action. The proteases are listed under EC3.4.x.x. Springer-Verlag Press publishes a set of 7 or 8 volumes of ring-bound EC classifications with a short set of properties and references. Each volume is 4 to 6 inches thick and updates are sent out regularly. The Springer-Verlag is a great source from which to launch a search. Let's be perfectly clear on one point. All of the alpha-amylase whether from barley or beans or bacteria or mice or men are classed as EC These enzymes do have different physical properties - different molecular weight, different temperature optima, different pH optima different co-factors. What they share is the same (or at least very similar) mechanisms of acting on their substrate. Enzymes are classified by function, not structure. And alpha-amylase from sources seemingly as similar as wheat and barley DO have different physical properties! Steve Alexander Return to table of contents
Date: Thu, 13 Mar 1997 02:06:08 -0300 From: Steve Alexander <stevea at clv.mcd.mot.com> Subject: Re: Protein terminology (part 2) Back to the questions from Harlan Bauer - Harlan asks specifically about the names protease, proteinase and peptidase. Without context these are common names and so the author, like Alice's Red Queen, can choose the meaning he/she likes. Note tho' that 'protease' is a recognised subclass of hydrolases which are enzymes involved the the hydrolytic elimination of a bond in protein. Proteinase, as a common name would most likely refer to any enzyme that acts on proteins and so could include not only the hydrolase.proteases, but also ligases, lyases ... . The mashing enzymes that we are most concerned with, the amylases, proteases and glucanases are classed as hydrolases - that is they catalyse the hydrolysis of bonds in amylose and proteins respectively. I believe that there are also some ligases involved in protein breakdown too. Peptidase is -often- used to refer to proteases that snip off only small peptides, or just amino acids from a protein. There is an analogy with beta-amylase which snips maltose from the non-reducing end of a polysaccharide and a pepidase snipping amino acids from a protein. Beta-amylase is also called an exo-amylase because is act on the external or end of a polysaccharide. Alpha amylase is an endo-amylase because it can act on interior bonds of a saccharide. Similar for endo- and exo-protease or peptidase. In an extremely interesting note on pp 270 of M&BS it is stated that in infusion mashes [enzymatic] proteolysis accounts for about half of the TSN (total soluable nitrogen) and alpha-amino nitrogen in the wort. This is attributed to heat-stabile endo-peptidases(!!) acting in conjunction with heat stable carboxypeptidases. It'd be interesting to read more on this. Your question implied that certain proteases will only attack amide bonds in selective weight proteins. I don't believe that this is the case. It's just that exo-proteases will only produce small bits, and endo-proteases will be more effective at reducing large proteins into small and medium sized bits for statistical reasons alone. To repeat the anolgy above, alpha-amylase is effective in breaking big polysaccharides into medium sized ones - but alpha-amylase will also measurably break dextrins into yet simpler sugars ! I'm not aware of a significant molecular size contraint on the substrate for the proteases. As a ballpark figure, amino acids range from a molecular weight of 89 to 204 and probably average around 133 or so. M&BS divide proteins into classes of <5000MW, 5-10,000MW, 10-50000MW, 50-100000MW and >100000MW. These 5 categories would translate roughly into <30 amino acid residues, 30-60 aminos, 60-300aminos, 300-600 aminos and >600 amino acids. As a point of comparison the mashing enzymes have estimateed molecular weights from 60,000 to 200,000 perhaps 450 to 1500 amino acids in their structure. Some as small as 213 amino acids tho'. How big is a haze forming protein ?? I don't know. There are probably factors other than protein size to be considered in haze formation. Steve Alexander Return to table of contents
Date: Thu, 13 Mar 1997 14:14:53 -0600 (CST) From: korz at xnet.com Subject: Re: decoction at mashout Tim writes: >I'm thinking of removing a third of the grains with a strainer (after >completion of mash) and transferring it to another kettle, adding water to >prevent scorching and boil for say 15 minutes and then return to the >mash tun for mashout. I guess I could pull grains and sweet wort to boil >since I am done with the enzymes anyway. This is risky business... one of the benefits of decoctions is that they release trapped starch from the steely ends of the barley. When you use a decoction to raise the mash to mashout, you should use only the "thinnest part" of the mash to prevent starch from being released. The "thinnest part" is often misunderstood... it means "just the liquid!" If you release any starch in the mashout (final) decoction, you have no "live" enzymes left to convert it once you add this decoction back to the mash... the mashout temperatures denature ("kill") all your enzymes, remember? Al. Al Korzonas, Palos Hills, IL korz at xnet.com Return to table of contents
Date: Thu, 13 Mar 97 15:29:31 EST From: "Kirk Harralson" <kwh at smtpgwy.roadnet.ups.com> Subject: Evaluating Starters A. J. deLange wrote: -snip- >and mimimum aeration. In checking a starter, therefore, what you are >looking for is the presence of bacterial infection. This tends to result >in foul smells rather than the admittedly unpleasant chemical smells and >tastes (very sour) of an otherwise normal starter. About the only comfort >I can offer is that with experience you will come to know what's normal >and what isn't. One of the main problems I had in evaluating starters was my abusive addition of hops to the starter media. Adding hops to starters for their anti-bacterial properties (whatever that is) has been suggested in books and in this digest in the past. I found that all my starters smelled and tasted like, well, hops and yeast whether they were contaminated or not. I canned 4 gallons of starter wort last weekend and added no hops in the hope that potential problems would be easier to spot before a whole batch is ruined. Kirk Harralson Bel Air, Maryland Return to table of contents
Date: Fri, 14 Mar 1997 09:37:00 +1300 From: Bruce Baker <Bruce.E.Baker at tsy.treasury.govt.nz> Subject: Live Beer G'day, I distinctly recall my first pint of beer in an English pub. I ordered a nice cold lager (I think it was an Australian brand) which lead to an earbashing from the bloke sitting next to me. He said I was drinking "dead beer", that is, beer without live yeast growing in it. He said I should be drinking "live beer", the warm stuff that lives in a big barrel in the basement of the pub. (Or at least that's my conception of how it looks.) Over the following week, I had quite a few pints of "live beer", pumped up out of the basement with hand pumps. My question is this: supposing I wanted to run a brewpub, offering authentic "live beer". What kind of hardware would I need? I'd also like to know: How do the hand pumps work? Do they pull the beer up with a "piston" or do they pressurise the kegs? What do the kegs look like? Stainless steel or wood? How long will the beer live before it goes flat? How do pubs get deliveries from the breweries? I think a brewpub serving live beer, or "Real Ale" could be a huge commercial success in New Zealand, where lots of people have ties to Mother England. Cheers, Bruce Return to table of contents
Date: Thu, 13 Mar 97 16:31:00 PST From: "Toler, Duffy L." <TOLERD at cdnet.cod.edu> Subject: RE: Mashout/Partial Decoction Tim Martin asks in #2373 about using a decoction as a mashout at the end of his mash program (currently done in a Gott without a mashout step) as a way of improving his beers. His plan was to pull the thick 1/3 of his mash, boil it and reintroduce it to the main mash. Tim... The biggest benefit of a mashout that I have found is that you pick up a couple of extraction points. I too mash in a Gott and do infusion and decoction mashes both. Usually, when I am doing an infusion mash, I will do a mash out decoction. Instead of pulling the thickest 1/3 (the grain) portion of your mash, pull the liquid 1/3 of the mash and heat it. This is how you perform a mashout in a classic triple decoction schedule. You could pull the thick portion and boil it if you were wanting some build some melanoidin character in addition to simply performing a mashout. Being lazy by nature (and having freakishly short arms), I find it easier to just crack open the outlet valve on the Gott mash tun and collect some wort in a boiler than to scoop out grain. YMMV Duffy Toler Sugar Grove, Illinois Return to table of contents
Date: Tue, 11 Mar 1997 10:54:30 -0800 From: George_De_Piro at berlex.com (George De Piro) Subject: RE: Yeast pitching / chocolate beer / burnt counter tops Hi all, Seeing as my E-mail service is erratic at best, and that there is quite a waiting list to get published on this forum, I don't know if/when this will get posted. Sorry if this gets posted so late that it is irrelevant. At least that "music-in-brewing" thread is getting posted. There were a couple of similar yeast pitching questions, so I'll address them both. Larry asks if you can repitch yeast from a bottle of homebrew. Yes, you can. Not only that, but you can pitch yeast from ANY beer containing viable yeast. You have to make a starter out of the yeast, though. There are several reasons for this. Two of the more important ones are: 1. There is not nearly enough yeast in a bottle of beer to pitch a 5 gallon batch. 2. The yeast will probably be sluggish at first, because it has been resting so comfortably in its beery surroundings. If you don't make a starter, the yeast will be very slow to start, and some may not start at all. There are other reasons to start the yeast fresh, like adapting it to the new environment that you are going to be pitching it into. Dennis asked a similar question about his yeast from Germany. Yes, it is probably still viable, but you should make a starter to wake it up. If it is lager yeast, then keep it cool for the entire process, so that you won't have to worry about temperature shock, etc. In all cases, taste the starter before pitching to make sure that it tastes clean!!! Never pitch a starter that tastes like it is infected! ------------------- Bob asks about brewing with chocolate. He mentions that he has heard of people just tossing some chocolate bars into the kettle. This will not yield good results if you use sweetened chocolate. The sugar in the candy is completely fermentable, and if a significant amount is used, the beer will become dry and thin. The bitterness of the chocolate then becomes harsh and overwhelming. Not good. You can use unsweetened chocolate (either block or powder). Be aware that either way, you will get an oil slick that kills head formation, so rack carefully to avoid getting the oil in the bottled product. Be sure to use a high mash temperature to ensure adequate residual sweetness, and use very little hops. The chocolate adds substantial bitterness to the beer. If making the beer out of extract, use one that you know finishes with a high gravity. The important thing to remember is that the chocolate needs sweetness to balance its bitterness and bring out its flavor. Choose a yeast that produces a malty beer, to help support the chocolate tones. I find Wyeast 1338 to be a good choice. 8 ounces of cocoa powder will give a subtle, but noticeable, chocolate character to 10 gallons of beer. ----------------- Bill asks about burnt counter tops. Yeah, mine is ruined, as is my stove top. I don't intend to fix either until I move or give up homebrewing! Also, NEVER put hot pots on synthetic rugs... Have fun! George De Piro (Nyack, NY) Return to table of contents
Date: Thu, 13 Mar 1997 18:54:02 -0700 From: brewshop at coffey.com (Jeff Sturman) Subject: dry yeast storage I need some help from the yeast experts. One of my customers recently had a terrible experience. He pitched one 14 gram sachet of Yeast Lab Whitbread Ale dry yeast into each of two fermenters, after rehydrating the yeast for 15 minutes in warm water. No action after 12 hours so he again rehydrated and then pitched again with the same yeast and 12 hours later (24 hours total) no activity was apparent. He then pitched one sachet of edme dry yeast into each fermenter and finally witnessed some activity about 8 hours later. He is positive that I sold him dead whitbread yeast. He says the reason the yeast is dead is because I keep it in a refridgerator. He read somewhere that dry yeast will go 'permanently dormant' if kept refridgerated. I have never heard anything like this and the particular yeast he had problems with has only been in my shop for about 4 weeks. BTW, I have sold dozens of sachets of this yeast, week after week for almost two years, and have had very few complaints. Almost every single person who uses this yeast is totally happy and in my experience it is a fast, clean fermenter as far as dry yeast goes. Out of curiosity I did an ultra high tech test on these sachets of whitbread yeast. I put 8 ounces of water and 2 tbsp of dry extract into each of three separate cups and then added whitbread yeast directly to each cup from three separate sachets. All three cups are now burping with activity after approximately 2 hours. The yeast isn't dead. I have talked with this customer extensively about his experience and I cannot figure out why the yeast didn't take. However, after being in this business for two years, and home brewing for about 5 years, I know that sometimes the damn yeast doesn't work and there is no reason why it didn't work it just didn't and no amount of reflection and contemplation will unravel the mystery because for some damn reason the yeast just didn't work...but when it happens to you it is frustrating and you tend to believe the damn home brew shop owner sold you some crappy, old, dead yeast. I know because it happened to me a couple of times before I opened my shop. But this particular case has me worried because the customer pitched two rehydrated sachets (apparently perfectly fit for fermentation) into two separate worts with no luck. I called my suppliers and they all agreed that refridgeration does not hurt dry yeast and three of my suppliers keep their dry yeast refridgerated prior to shipment to home brew shops. So, what gives? Does refridgeration damage or kill dry yeast? This customer is adamant about this and I don't have any solid proof to show him that refridgeration is not detrimental to dry yeast. I'm just looking for some credible evidence that I can show to this customer to ease his worries about the evil home brew shop owner who is trying to spoil his beer. TIA for any assistance. And sorry this is so long winded and really irrelavent to this group. For punishment I won't drink any home brew tonight :) yeah right! jeff casper, wy Return to table of contents
Date: Fri, 14 Mar 1997 08:33:47 -0500 (EST) From: Eugene Sonn <eugene at dreamscape.com> Subject: brews for a wedding Hi HBDers, Two friends of mine just got engaged and I've promised to brew four batches of beer for the wedding reception. I've got three out of four beers selected: Oatmeal Stout, Steam, Strawberry Wheat. My questions is I haven't figured out what to brew for the fourth beer. Any suggestions? I know several people have posted about brewing for weddings before. I'd love to hear what beers you folks selected. Thanks in advance, Eugene eugene at nova.dreamscape.com Return to table of contents
Date: Fri, 14 Mar 1997 08:33:52 -0500 From: "David R. Burley" <Dave_Burley at compuserve.com> Subject: Lactoak, sour mash Brewsters: AlK asks about oak chips as a source of lactobacillus. I was in a HB store and a new brewer came in with his first beer that was spoiled - an extract lager which he had treated with oak chips. (he "read it in a book"). I was called over by the store owner and asked to taste the beer. The store owner pronounced it as an acetic infection - which it was not. When I suggested that it was a lacto infection and that in the future the brewer should first sterilize the oak chips in a pressure cooker, the store owner wasn't happy and said "there's a lot easier way to sterilize oak chips than a pressure cooker" and I said "Name one". I later apologized for butting in by offering an opinion when I had been asked for one. I admit I should mind my own business in other people's stores, but I hate to see bad advice being given and no advice given on how to handle unusual ingredients. Oak chips should be sterilized ( yep) in a pressure cooker, 10 minutes at 15psig. Put them in a bowl on a rack above the water. I suppose boiling is better than nothing, but use the water also, since most of the tannin will be in there. Don't boil too long as most of the vanillin will evaporate, but how long is long enough and not too long? I don't know. The advantage of the pressure cooker is that the pressure penetrates into all the pores, whereas the water is still at atmospheric pressure and can't displace the air in the small pores or heat the non-conducting wood easily. I have used lightly toasted French oak in preparing several beverages to good effect. - ----------------------------------------------------------------------- Speaking of Lacto infections, Jim Cave believes there is NO reason for brewers to do a sour mash. As long as this is exactly what he means, I agree. No one should infect their whole mash, or worse, their beer with lactobacillus directly. If you wish to add a sour (or "stale") beer in making an Entire Porter or Entire Stout Porter, sour about 3% of your batch, sterilize it by boiling, and add this to taste to your finished beer. This "additive" is reputed ( with no confirmation from Guiness) to be the secret ingrediernt they send out to all their subsidiaries around the world. I have tasted some Guiness in past years that did have some enteric qualities. Keep on brewin' Dave Burley Kinnelon, NJ 07405 103164.3202 at compuserve.com Voice e-mail OK Return to table of contents
Date: Fri, 14 Mar 1997 08:57:27 EST From: "FINLEY, BARRY CURTIS" <BFINLEY at MUSIC.CC.UGA.EDU> Subject: where to buy hop plants I am curious about growing my own hops. Shouldn't be to hard, my mom is an avid gardner and horticulturist. But I have no idea where I can buy the hops in the first place. Are there any good mail order companies that you have had good results with? Please inform me. Thanks, Barry Finley Return to table of contents
Date: Fri, 14 Mar 1997 08:37:23 -0600 From: Bill Giffin <billgiffin at maine.com> Subject: Decoction mashing Top of the morning to ye all, Chris Pertschi said: >You can add 'foundation' water to your decoctions & stir almost constantly to >avoid scorching. I don't add any foundation water to a decoction. I do not find that it is needed. What is needed is a decoction kettle that has a heavy flat bottom, which will evenly distribute heat. The heat applied should be low. The temperature should only increase about 2 degrees F per minute. This way I only have to stir only every 10- 15 minutes utill it comes to a boil and then it so liquid that a couple of stirs during the boil is all that is required. The key is a good pot and slow heating. I have done some where around 100 decoction mashes. I can tell you that cleaning up a scorched pot isn't fun so go slow and it will be easy. Bill May you be in heaven an hour before the devil knows you are dead, Bill Bill Giffin 61 Pleasant St. Richmond, ME 04357 (207)-737-2015 All you need is a few good friends and plenty to drink because thirst is a terrible thing! Return to table of contents
Date: Fri, 14 Mar 1997 10:50:15 -0500 (EST) From: KennyEddy at aol.com Subject: Runoff Gravity Change Equation / Keg Chillers Mark Prior is asking for an equation to predict runoff gravity during a sparge: "I am interested in understanding the changes in specific gravity during the sparge of an all grain beer." First, according to the priciples of "parti-gyle" brewing (whereby different worts are made from different parts of the runoff), two-thirds of the gravity are found in the first half of the runoff. This has been discussed here (early this year by Alex Santic) and there's an article in one of the back issues of Brewing Techniques covering this. Second, it might be reasonable as a first pass to assume an exponential curve. I've plotted this data once in the past (don't have the actual data anymore, sorry) and visually the curve "looked" exponential, so let's start with that. So the first crack at the equation would be of the form G/G0 = e to the -a*v/v0 G/G0 is the ratio of the current runoff gravity (G) to the starting runoff gravity (G0), after running off volume v from an initial volume v0 (got it?). "e" is the natural exponential operator ~ 2.7183. Solving for a using G/G0 = 1/3 (2/3 of the gravity is gone) when v/v0 is 1/2 the equation is G/G0 = e to the -2.2*v/v0 Tabulating at 10% intervals: % volume remaining % gravity 0 100 10 80 20 64 30 52 40 41 50 33 60 27 70 21 80 17 90 14 100 11 This may be a ways off but it' should be a reasonable place to start. Any other thoughts? ***** Louis Bonham wrote (after appropriately bashing Peltier junctions): "My bottom line -- just scrounge up an old working fridge or freezer. Not real fancy, but they really work. :)" I've also messed with Peltier junctions and have to agree 100% with Louis. A while back on this forum, there was a post by an individual who makes refrigerated wine cellars using those little "cube" refrigerators. The idea is to *carefully* "cut away" the cooling mechanism from the refrigerator housing (which is mostly just plastic and/or sheet metal). After discarding the refrigerator housing scraps, you're left with the compressor, the plumbing, and the box- or tube-shaped freezer (which is the cooing end of the circuit). This is then carefully installed in the new wine-cellar cabinet, which is custom-built for the application. No recharging or reassembly required, a good thing considering the high pressures involved and chances for disaster should your soldering be less than perfect. A small circulation fan wired across the compressor (after the thermostat) would aid in more-efficient cooling. If you're handy with basic woodworking, you should be able to rig up a nice refrigerated cooler for two or more kegs for well under $150, cheaper if you can get the fridge used. Remember too that if the kegs are cold going into the cooler, and the cooler is well-insulated, only a small amount of power is required to *maintain* the temperature. To *chill* from room temperature may take a while but if you plan ahead (for your porta-parties) you should accomplish your mission. ***** Ken Schwartz El Paso, TX KennyEddy at aol.com http://members.aol.com/kennyeddy Return to table of contents
Date: Fri, 14 Mar 1997 08:34:40 -0800 From: popeman at webtv.net (Tom Pope) Subject: foamy beer Ian Smith wrote about foamy beer from his keg. I would suggest that he check his product tube,valve, disconnect, hose and tap for clogs of particulates. If there is any major obstruction, the effect is much like that of a stout shear tap; major foaming... As a last resort, I would check the accuracy of his gas gauge readings by comparing them against reradings from other gauges.. My experience has been that a lot of these gauges are not terribly accurate, but if you use one for awhile, you get to know what readings produce desired results for your set-up. Tom Pope The Pope of Corte Verona Return to table of contents
Date: Fri, 14 Mar 1997 08:47:24 -0800 From: popeman at webtv.net (Tom Pope) Subject: foamy beer Ian Smith wrote about foamy beer from his keg. One source I haven't seen posted is a clogged product tube, valve/poppet, disconnect , hose or tap.. Hop fragments or any other solid matter can clog any of these areas and will act much like a shear tap in producing very foamy beer.. I've had this experience on only one occasion with a dry-hopped batch of English bitter. If this doesn't solve the problem, check accuracy of your gas gauges.. Some gauges are not very accurate and it's a trial and error thing to get the pressures that work right for carbonating and dispensing your kegged beer. The Pope of Corte Verona Return to table of contents
Date: Fri, 14 Mar 1997 11:18:20 -0700 From: "Brian M. Rezac" <brian at aob.org> Subject: Re: Pubs in UK Rick Gontarek wrote: > I am fortunate enought to be going on a business trip to the UK the > week of 22 March. Since this is my first visit, I would like to get > some input regarding great little pubs to visit. I will be staying two > nights in London, then a few in Cambridge, and then a few evenings at > one of my company's R&D facilities in Harlow. If anyone has any advice > on where to sample beer, I would greatly appreciate it. BTW, I have > heard of CAMRA's guide to real beer in the UK, but since time is > short, I won't have the chance to run out and get it. Any summaries > are welcome. > > Also, any hints on yeast strains to bring back? > > Thanks a ton, > > > Rick Gontarek > Owner/Brewmaster of the Major Groove Picobrewery > Trappe, PA > gontarek at voicenet.com Rick, I'm envious! You may want to try the UK Homebrew EMail Discussion List/Digest Forum. They could probably give you very good advice on all your inquiries. Here is how you get in touch with them: To submit messages to the list/digest, address them to... uk-homebrew at rhbnc.ac.uk To subscribe or unsubscribe, send a message with one or other of the following commands in the message body (no other text) to... uk-homebrew-request@ rhbnc.ac.uk SUBSCRIBE - Subscribe to INgest form. UNSUBSCRIBE - Unsubscribe from INgest form. SUBSCRIBE DIGEST - Subscribe to Digest form. UNSUBSCRIBE DIGEST - Unsubscribe from Digest form. Good Luck & Good Beer! Keep Brewin' - Brian Brian Rezac Administrator American Homebrewers Association (303) 447-0816 x 121 (voice) 736 Pearl Street (303) 447-2825 (fax) PO Box 1679 brian at aob.org (e-mail) Boulder, CO 80306-1679 info at aob.org (aob info) U.S.A. http://beertown.org (web) Return to table of contents
Date: Fri, 14 Mar 1997 12:33 -0600 From: M257876 at sl1001.mdc.com (BAYEROSPACE) Subject: ban the sour mash collective homebrew conscience: jim cave wrote: >The sour mash rears it's ugly head again!!<snip> >I think homebrewers have been mislead by the advocates of this process. >FOR GOODNES SAKES, GIVE IT UP!!!! Enteric bacteria are involved, as >well as lactic ones, and they add sewer like flavours to your beer. There are >really no good reasons for homebrewers to do sour mashes, unless you have to >make a pilsner with higher pH water and have some fanatical desire to adhere >to the reinheitsgebot! Otherwise, why not add lactic acid?? >There is no good reason for a homebrewer to do sour mashes. i've edited jim's submission, but i take issue with the above generalized statements. it is my personal opinion that there are some valid reasons for doing sour mashes, and this opinion is based on my personal experience. my sour mash weizen won best of show at memphis last year. i brewed another one this year that was tasted last month at the saint louis brews homebrew meeting. none of the comments included "sewer-like". to the contrary, it was well-received. so i would disagree, based on personal experience and the judgments of many others, that sewer-like flavors were added to my brews by the sour mashes. plus, it's very possible to overdose on lactic when you're adding it from a bottle that says "85%" or some other number that may be questionable. a sour mash has virtually no chance of doing this. the amount of grain you put in it limits the quantity of acids it can produce. this is a minor argument, i think, though i did actually screw up a mash one time by adding lactic acid from a bottle. if somebody could tell me exactly how much of a given percentage of lactic acid i could put in my beer to *approximate* the flavor profile i get from sour mashing, i would be more likely to try it. but i already have a collection of good recipes using this method, and they work fine and make great beer. i'd like to keep "tweaking" them, instead of reinventing them. i agree completely that this is an outdated, traditional, empirical method of producing lactic acid. just like decoction mashing is a traditional, empirical, outdated method of mashing, with all the well-modified malts we have available these days. despite this, i use both of these methods. i also agree completely with jim that it's not just lactic bacteria at work in the sour mash. there is definitely a difference in the way a sour mash smells versus a bottle of lactic acid. i've not noticed "sewer-like" smells from the sour mash, but i always pick up aromas reminiscent of corn and sauer kraut. they blend great with the malt flavor. i don't believe that these flavors and aromas could come from a bottle of lactic acid. the sauer kraut smell, in particular, convinces me that the south german beer gods are smiling. brew hard, mark bayer Return to table of contents
Date: Fri, 14 Mar 97 12:32:09 CST From: jwilkins at imtn.tpd.dsccc.com (John Wilkinson) Subject: Re: decoction at mashout Jeff Renner wrote: >The point of mashout is to destroy enzymes and stabilize the wort. I have heard this before but never understood it. Why destroy the enzymes? What is meant by "stabilize the wort"? If there is starch present in the wort, wouldn't you want the enzymes to remain active to reduce them? If there is no uncoverted starch present, what difference does it make if the enzymes are denatured or not? I know Jeff knows a hell of a lot more about brewing than I do but the only reason I can see for raising the mash temperature to ~170F would be to promote the dissolving of sugars into the liquid. Where have I gone wrong in my thinking? John Wilkinson - Grapevine, Texas - jwilkins at imtn.dsccc.com Return to table of contents
Date: Fri, 14 Mar 1997 12:33:46 -0600 From: Dave Hensley <dhensley at telecom.tandem.com> Subject: Re: HBD Dist List Use I've been getting several junk e-mails a week for the last 2 weeks also. = I haven't been able to determine where they have been getting my e-mail = address from. All of them require a "remove" response since they all = promise (threaten) more e-mail to follow. Note that none of these = e-mails was for anything related to liquid refreshment. Is it possible = to restrict the address list without a lot of effort? BTW, the S/N looks about the same now as it has during the last 6 or so = years (including the periodic S/N debates). The Digest is still the best = thing on the net. Thanks to all for the great posts. - -------------------------------------------------------------------------= - ------------------------------------ Dave Hensley Tandem Telecom Network Systems Mail: dhensley at Xtelecom.tandem.com Web: http://www.tandem.com Return to table of contents
Date: Fri, 14 Mar 1997 14:10:20 -0500 (EST) From: KennyEddy at aol.com Subject: '70's Flashback -- Miller Proud of Bland Beer; Secures Patent This is an excerpt from an actual patent issued in 1979 to Miller Brewing Company. I think it pretty well sums up what we already know. #4180589 Preparation of a bland beer INVENTORS: Chicoye; Etzer, Milwaukee, WI Helbert; J. Raymond, Waukegan, IL Rice; James F., Milwaukee, WI ASSIGNEES: Miller Brewing Company, Milwaukee,WI ISSUED: Dec. 25, 1979 FILED: Dec. 28, 1977 ABSTRACT: A method of preparing a lager beer having a mild, bland, less aromatic character comprises conducting the fermentation of the wort for about 60 to 200 hours under suitable conditions to maintain the dissolved carbon dioxide concentration in the fermenting wort at about 2.1 to about 4.0 cc of dissolved carbon dioxide per cc of wort. In a preferred embodiment, the fermentation of the wort is conducted at a temperature of 60 deg to 85 deg F. with an appropriate overpressure of from 5 to 40 psig of carbon dioxide. The beer thus obtained has a mild character and can be used, if desired, as a base for flavored beverages. CLAIMS: We claim: 1. A method of preparing a lager beer having a mild, bland, less aromatic character which comprises placing beer wort in a fermentation vessel and fermenting the wort in said vessel for about 60 to about 200 hours at an elevated temperature of 60 deg F. to about 85 deg F. while maintaining the dissolved CO2 concentration in the fermenting wort at about 2.1 to about 4.0 cc per cc of the fermenting wort by use of a CO2 overpressure in the vessel of about 5 to about 40 psig. **** The last sentence of the abstract offers a marginally legitimate excuse for such a process, but one could surmise that the idea spread across the product line. On a more serious note, I wonder if this process relates to the recent question of CO2 toxicity by Alex Santic and fermenting under pressure by Scott Murman? ***** Ken Schwartz El Paso, TX KennyEddy at aol.com http://members.aol.com/kennyeddy Return to table of contents
Date: Fri, 14 Mar 1997 14:53:14 -0500 From: Steve Alexander <stevea at clv.mcd.mot.com> Subject: re: heterofermentative bacteria All, I sent a longer version of this to George with more detail. The shorter version is .... George Fix wrote ... >In HBD#2371 S. Alexander writes: >> BTW G. Fix in PoBS claims pediococcus are hetrofermentative, >> every other source I've checked lists pedeococcus as >> homofermentative... > >Most pedios known to me are capable of producind acid and large >amounts of diacetyl among other things. This is what I meant by >heterofermentative, i.e., produces more than one product. The key distinction I believe isn't the array of products so much as the metabolic pathways involved. Homofermentative bacteria use the E-M-P pathway, heterofermentative bacteria follow the pentose phosphate pathway and generate significant amounts of CO2, ethanol and acetic acid. I have a lot of microbiology references that pediococcus IS homofermentative (available on email request). I don't see any reason why a homofermentative bacteria couldn't produce objectionable levels of diacetyl (with a sensory threshold around 0.1ppm it doesn't take much), tho' I can see some reasons why we might expect diacetyl to potentially be a bigger problem with hetero's. n.b. lacto brewers may want to check out http://www.danonenewsletter.fr/ for their newsletters. Good reading, quite detailed technical info on lacto cultures. This is Dannon Yogurt's parent company I believe - no affiliation. >Alexander continues: >> ...maybe another case for AlK's errata web site > >Sure, but who is looking after the dismal signal to noise ratio >on this forum. I guess I'm really at a loss over this last statement, so let me make my position clear. Principles of Brewing Science is a great book IMO. Full of excellent information, well written and organized, up to date, excellent lit references, and affordable to the HBer at around $30. No other Homebrewing oriented book comes close in terms of accuracy and detail. Please don't take anything I've said about corrections to PoBS as general criticism of the book, it certainly wasn't meant that way, but this book, like any other contains a few errors or points in doubt which, because of it's value as a reference book, are in need of notation. I have a short list for PoBS, several typo, several heading and a few minor factual errors. Since you've set the expectation that PoBS is a reference work for HBers, I believe these should be addressed. If you won't ... I guess that leaves the door open for others to comment. Frankly PoBS is one of the few HB books worthy of a critical reading - many are filled with fluff and 'half-science'. Is the SNR on HBD 1997 more dismal compared to earlier years ?? I've just reviewed a couple of issues back from 1988 to 1992 era. The noise and the signal were both clearly present back then as today, tho' the tenor of each has changed a bit. I think that many HBD contributers (mea culpa) could stand to review their posts for relevence, utility and courtesy before posting. George, your contributions to HBD are numerically few recently, but they are real gems to the homebrew world. You obviously have a wide range of experience and have access to professional brewing literature that is difficult for most of us to obtain. The long threads and lively discussion related to First wort hopping, no sparge brewing and the 40-60-70C mash schedule (a few that come immediately to mind) indicate great interest in the topics you present to HBD. Please don't be discouraged. Steve Alexander P.S. I'm still looking for your new book George, any updates on when in "early 1997" we should expect it ? Return to table of contents