Homebrew Digest Tuesday, 2 July 1996 Number 2090

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

Contents:
  Light on Samuel Smith's ("Crist, Tim")
  1996 Colorado Brewers Festival (John Adams)
  1-4 links vs 1-6 links (Steve Alexander)
  Primary Yeast Dreg Problem (paa3983 at dpsc.dla.mil (Mike Spinelli))
  RE: 140^F rest ("CHUCK HUDSON, ER LAB 3-2865")
  esters and flavor/post fermentation ester formation (Anders Lundquist)
  Anheuser-Busch SBG Website (korz at pubs.ih.lucent.com)
  maltose syrup (blades at airtime.co.uk (Liz Blades))
  mixed bag.... (Dckdog at aol.com)
  Boiling wort in a pressure cooker, Crystal Budweiss clone (Michael_Evans at FRB-MAIN-2.CCMAIL.CompuServe.COM)
  Ancient Yeast DNA, taste (Jeremy Bergsman)
  RE: Will this make it??? 5th try ("CHUCK HUDSON, ER LAB 3-2865")
  Igloo mash tun (John Wilkinson)
  misread (Kyle R Roberson)
  Hot O2 or not to O2? post#2 (Charlie Scandrett)
  Enzymes - (sources) (Steve Alexander)
  BUZZ-Off results (BrewIPA at aol.com)
  Re: HSA - Chill to 35 F  ("Sharon A. Ritter")
  Re: Radiator hose for RIMS (hollen at vigra.com)
  How to clean up a boilover? (jfrodriguez at jfrodriguez.seanet.com (Joe or Sue Rodriguez))
  Three stage cooler (The GasFamily)

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---------------------------------------------------------------------- From: "Crist, Tim" <Tim.Crist at alliedsignal.com> Date: Mon, 1 Jul 1996 14:12:00 -0700 Subject: Light on Samuel Smith's Dear Collective: I recall reading a thread on skunked beer via light contamination. I'm sure that Sam Smith's is very sensitive to this phenomenon since they only use clear bottles. At a BSBC (Bull and Stump Brew Club, Kokomo Indiana) party some years back I brought a six pack of Sam Smith's Winter Welcome Ale. Upon opening, each of the six had a foul smell and nasty taste <- descriptive enough? I had had some of this beer earlier in the year from the same store and it was great. So now I'm thinking light contamination since the store in question prominently displayed their beer under the fluorescent lights. Well now I live in Tucson. While at a local beer and wine market I noticed the Sam Smiths out in the open again. I remarked to the manager of fermented goods that she should stash them out of the light. She agreed to move them as long as I could provide her with some explanation of what was happening, and recommend proper storage. She also noted that the store used halogen lamps instead of flourescents. In turn, she was going to ask here importer and Samuel Smith's Brewery the same. If I get any useful info from her, I will post it. In the meantime, can anyone help me with the specifics of what wavelengths do the damage, how the damage is done, and what is the primary wavelengths of halogen lamps? Thanks, Tim Crist Return to table of contents
From: John Adams <jadams at pipeline.cnd.hp.com> Date: Mon, 1 Jul 1996 07:36:33 -0600 Subject: 1996 Colorado Brewers Festival The Colorado Brewers Festival was held Saturday and Sunday June 29 and 30= in Fort Collins, Colorado. Saturday was a fantastic Colorado summer day,= the beers refreshing, and the downtown atmosphere was perfect. Last years festival was (unfortunately) held in a less than ideal parking= lot (due to construction downtown) but this year's event returned to Olde Tow= n = with 21 beers from 21 breweries. This is the original Colorado-only beer= = festival and still better than the Lodo fest I attended last weekend (eve= n thought they used last year's mugs). Many of the beers were nothing fantastic (but good never the less), one b= eer = bad enough to find the spooge bucket, but my 'best of show' goes to IL = Vicino's Wet Mountain IPA with B.F. Coleman and Palmer Lake breweries as runners up. John Adams - --- Range River Red (4 stars) B.F. Coleman Brewing (Judge Baldwin=92s) Colorado Springs, Colorado A nice dry hoppy flavor. Flavored with a hint of raspberry and wheat, th= is = has a slight raspberry tartness and very very drinkable -- Nice! Honey Rose Amber Ale (2 stars) The Coophouse Brewery Broomfield, Colorado The Coophouse recently went from extract to all-grain. This is a pleasan= t spicy ale, with a little diacytle that is noticeable. Clean and drinkabl= e. Duke of Ale (2 stars) Fleetside Pub & Brewery Greeley, Colorado Not a bad beer (maybe it just the big pour)! A roasty taste that has a slightly astringent taste. Slightly hoppy and finishes dry. Wet Mountain India Pale Ale (5 stars) IL Vicino Oven Pizza and Brewery Salida, Colorado YUM! Very hoppy, slightly bitter IPA. Nice centennial hop character tha= t = has a dry finish. This beer wins my personal Best of Show. Seamas' Irish Red Ale (3 stars) Namaqua Brewing Company Loveland, Colorado Namaqua had a very good beer at the Lodo fest so I had to check them out.= A nice mild-medium bodied ale. Slightly bitter, dry finish and clean. V= ery pleasant beer. Levity Ale (3 stars) Odell Brewing Fort Collins, Colorado Nice clean, mild taste that is slightly sweet. Not too much or too littl= e, very quenchable. Palmer Lake Cherry Velvet Porter (4 stars) Palmer Lake Brewing Company Plamer Lake, Colorado A recent arrival that is doing something right: two awards at the World B= eer Cup and my 'Best of Show' at the Lodo fest. This beer is velvety and smo= oth. Slightly tart finish and creamy. Cherry Lager (0.5 stars) Powers Brewing Company Brighton, Colorado This beer was really bad, it gets my 'Dog Award' (which is not given very= often). Oxidized and astringent, YUCH --I dumped this beer after two = swallows! Pick Axe Pale Ale (3 stars) Tommyknocker Micro-Brewery Idaho Springs, Colorado A slightly bitter beer that has a medium hoppiness. Needs a little more = hop flavor, pleasant and drinkable. Slightly astringent. Rattlesnake Kate=92s Vienna Lager (2 stars) Union Colony Brewery Greeley, Colorado A nice clean lager. Spicy and refreshing but nothing out of the ordinary= =2E Artic Wheat (3 stars) Mountain Sun Pub and Brewery Boulder, Colorado I finished the day with this unique, lemongrass and mint wheat beer. Ver= y nice for a hot summer day beer. Lemony freshness made this a very refres= hing beer. Return to table of contents
From: Steve Alexander <stevea at clv.mcd.mot.com> Date: Mon, 1 Jul 1996 17:36:10 -0400 Subject: 1-4 links vs 1-6 links Al K wrotes ... >There is also the factor of 1-6 links, which are the key (if memory serves >correctly) to "limit dextrins," the dextrins that can not be cleaved by >alpha amylase (although I believe that beta amylase does nibble off maltose >molecules from their ends). I faintly recall that the beta amylase only >cleaves off maltose from *one* end of the chain. Once it hits a 1-6 link, >that's all, folks. Is that right, Steve? Right - except the parenthetical bit requires more explanation. Beta-amylase and alpha-amylase both break 1-4 links. Beta amylase removes 1-4 linked disaccharides from the NONREDUCING end of a starch which in turn become maltose. If the nonreducing end of a starch chain is near a link other than a 1-4 (such as a 1-6 link or a 1-3 link) then the beta-amylase can no longer act, and we have a beta-limit dextrin - and these can be big ugly starchs. Alpha-amylase needs a site with at least three 1-4 linkages in a row to act. But even if there are three 1-4 links, they may be situated in such a way, near branches, that they cannot be accesses by the 'business end' of the alpha-amylase enyzyme. So there are a lot of complicated, difficult to define structures for alpha-limit dextrins. Mostly they are smallish, from G4 to around G30 in size, and can include a substantial number of branches. So alpha-1-6 links often define the beta-limit dextrins, and alpha-limit dextrins too. When alpha-amylase snips a 1-4 link in the 'middle' of a long starch, it (usually) creates a new nonreducing end for the beta-amylase to work on. Debranching enzyme and alpha-glucosidase, the other two important amylolytic enzymes found in germinating barley, can each break 1-6 bonds, and thus degrade limit dextrins. Only a small but important amount of each survives kilning. As you've pointed out before Al, reducing all the carbs to fermentable form is NOT the point of making beer. The non-fermentables dextrins are a major part of the flavor and sensory effect of a beer. Incidentally several recent posts and some brewing books incorrectly indicate that beta-amylase removes disaccharides from the REDUCING end of an amylose; it should read the NONREDUCING end according to the sources I reference. Steve Alexander Return to table of contents
From: paa3983 at dpsc.dla.mil (Mike Spinelli) Date: Mon, 01 Jul 96 17:45:27 edt Subject: Primary Yeast Dreg Problem HBDers, A question to all those who repitch using the primary dregs from previous batches. How long is the yeast viable when stored in a ball jar in the fridge? The reason I ask is I just pulled out a jar of yeast from the fridge that was about a month old. It would've also been the 3rd generation of Brewtek CL-160 British Draft Ale strain. Cooked up 1/2 gallon of wort , cooled and aerated it, then dumped the warmed up yeast slug onto the wort. I expected a violent ferment and a finish within hours, however the next day I checked the gallon jug and noticed all the yeast was settled out. It didn't look quite right to me so I checked the gravity and tasted it. Sure 'nuf the gravity didn't budge from the original of 1.035 and the taste was sweet. This is the first time I've waited longer than 2 weeks to repitch the primary dregs. All the other times went w/o a hitch and didn't even require making up a new starter. I was led to believe that yeast slugs can be fridged for as long as 6 months. My system was thus: 1 - Pressure cook the ball jar, let cool 2 - Rack beer, swirl up dregs, dump in jar, cover w/2 sheets Saran and then foil 3 - Stick in fridge What happened? Mike in Cherry Hill NJ Return to table of contents
From: "CHUCK HUDSON, ER LAB 3-2865" <CHUDSON at mozart.unm.edu> Date: Mon, 1 Jul 1996 16:03:01 -0600 (MDT) Subject: RE: 140^F rest Greg asked about a certain type of bacteria that I added to malt for vinegar, to be formed, Acetobacter is a common bug that floats around but you would be best to purcahse a starter from your local homebrew store, most have mother of vinegar if not the way I found my starter was shooping at Albertsons and found two bottles of vinegar with the mother growing in them and I have been using the same staters for around two years. Just one word of warning (Warning Will Robinson) Keep it as far from your brewing area as possible it will migrate by air currents and attack your beer. Chuck chudson at mozart.unm.edu Return to table of contents
From: Anders Lundquist <Anders.Lundquist at bion.kth.se> Date: Tue, 02 Jul 1996 00:18:51 +0200 Subject: esters and flavor/post fermentation ester formation This got rather longer than I intended, ah well... In Digest #2087 Tracy Aquilla <aquilla at salus.med.uvm.edu> wrote: > I believe the idea that the tongue can only detect sweet, salty, sour, and > bitter is very old and has been disproved. I thought this was still valid, if this has changed, I'd like to hear some more on it. > It is also essentially impossible > to separate taste from smell, as smell contributes significantly to taste. > Esters do have flavor. If they didn't, most foods would taste very bland. In a general meaning, you're quite correct, but I think there might be some terminology confusion here. Waving my dictionary, I quote: taste -n. 1. a. The sense that distinguishes the sweet, sour, salty, and bitter qualities of dissolved substances in contact with the taste buds on the tongue. b. This sense in combination with the senses of smell and touch, which together receive a sensation of a substance in the mouth. So we have: taste (general meaning) = taste (strict meaning) + smell + mouthfeel This, by the way, is more than I learned at school, I don't recall any mention of the mouthfeel part. Is this perhaps what you meant above? So, can you taste esters? Depends on what you mean with taste. In the general meaning, obviously yes; in the strict meaning, it seems not (judging by Andy's experiment, but for all I know, other esters might have some strict meaning tastes). I just did a (very) quick check of a psychophysics textbook: - - I didn't see anything on mouthfeel (but I might have missed it). - - They mention two different "modes" of smelling: distance smell and food smell, and mention that they can give quite different results (to me this suggests some synergetic effect between smell and taste). - - They use taste in the strict meaning only. - - They use flavor for the general meaning. This taste-flavor distinction is what I try to use in English (no such luck in Swedish, there's just one word for it all). Unfortunately, this doesn't work well in verb form, since 'to flavor' means something else. The textbook uses 'to experience flavor' for the verb, which is fine for a textbook, but rather awkward for everyday usage. So in the end, I still say that I want to taste a beer, but if asked how it tasted, I describe the flavor... (and if I liked it) ObBrewing: You and others wanted to hear results from individuals. So I offer the following anecdote, which isn't directly about aeration and fermentation ester formation, but relevant anyway, I think. Once upon a time I brewed what was intended to be a Belgian Triple. Details on grain bill etc available if anyone's interested. I fermented the beer fairly warm (about 21-22C ambient). However, due to the small volume (less than six liters), and the rather slow working yeast (cultured from Hoegaarden Wit), the actual fermentation temperature might not have been much above ambient. Nonetheless, at bottling time it had a fairly high level of what I concluded was fusel alcohols. While the beer was some 10% abv, the sharp, burning alcoholic flavour was too much to just be ethanol. I was somewhat disappointed, and thought it wouldn't get any better, since I couldn't think of any way for the fusel alcohols to get broken down into something simpler. It just didn't occur to me at the time that they might combine with something, and form more complex molecules instead. High school chemistry temporarily all gone. Anyway, I sampled the occasional bottle of it, and some time later (not sure how long, a few months perhaps; long after carbonation at any rate) I was in for a surprise. From one bottle to the next (with a week or month between them, again I don't recall) the fusel alcohols were all but gone, and instead the beer had the most intense raspberry aroma I've ever tasted in any beer short of Liefman's Frambozen! While the raspberry aroma was rather one-dimensional compared to that of real raspberries, it made for a very nice effect nonetheless. I loved this beer. Enough so that I would like to try to reproduce the result sometime, but I have no idea if this is reproducible, or if I was just plain lucky that time. Some other probably relevant data: - - Probably underpitched. For high gravity beers, I normally use the dregs of a previous batch, but this time it was just a starter. While I don't have any note on the size of it, I'd guess it was an underpitch, despite the small batch volume. - - No note on aeration unfortunately. But if I did things my normal way, I shook the bucket (with lots of headspace) for a couple of minutes, and repeated a few times during the evening (aeration with yeast). - - At bottling time, I added fresh yeast (same strain), as recommended for high gravity beers. I've got the impression that the fresh yeast might be very important for the rate at which the ester formation happens, not sure where I got that from. I know far too little about what really goes on here, that there's little point in starting to ask about specifics. So, I'll just throw out the big one: is there any significant risk of backfire? I wouldn't mind so much if I got the "wrong" ester, that would probably just be another nice surprise. However, I'd hate to intentionally promote fusel alcohols only to find that they refuse to turn into esters... Anders - --- Anders Lundquist (andersl at bion.kth.se) http://www.bion.kth.se/~andersl/ Return to table of contents
From: korz at pubs.ih.lucent.com Date: Mon, 1 Jul 96 17:14:34 CDT Subject: Anheuser-Busch SBG Website A few weeks ago, I stumbled upon the A-B Specialty Brewing Group Website. Some pretty cool stuff there. I posted a comment to "Ask the Brewmasters" and it appears to have been "answered." The home page of the site is at http://w3.hopnotes.com/hopnotes/garden/index.html and my "question" and their "answer" are at http://w3.hopnotes.com/hopnotes/garden/styles.html Frankly, I'm surprised they bothered with my "question." Al. Al Korzonas, Palos Hills, IL korzonas at lucent.com Return to table of contents
From: blades at airtime.co.uk (Liz Blades) Date: Mon, 1 Jul 96 23:15:55 BST Subject: maltose syrup Hi, In hbd # 2089 Greg King wrote "One of the adjuncts called for in some of the recipes is maltose syrup, which I am unfamiliar with. Do any of you know if this is available in the US? If not, any ideas on what a good substitute might be?" I don't know what Graham was thinking about when he wrote this,but the product isn't available in the UK either!!!!!!! I suggest you use either LME or barley syrup. Cheers Liz Blades Liz Blades Proprietor of Blades Home Brewery http://www.dmatters.co.uk/Blades/blades.html Return to table of contents
From: Dckdog at aol.com Date: Mon, 1 Jul 1996 18:51:46 -0400 Subject: mixed bag.... Greetings, *A good friend of mine loaned me some Better Winemaking magazines from the early 90's. This is a Canadian publication that apparently took a powder and is now reforming to start publishing again. It has (had) great information on winemaking and suprise, a lot on homebrewing. In the issue dated winter 1990 it mentions a TVO presentation of a three part series on homebrewing, did anybody see (tape) it? Has it aired recently? *A few weeks ago a beginner, like myself, asked what the next logical step was from brewing extract. I think the gist of his post was how do I quit making homebrew that tastes like homebrew. Was full wort boil mentioned? If so, what is the easiest way to do it? I still used dry packaged yeast (Superbrau usually) does rehydration really add anything to the finished product? How difficult is it to use liquid yeasts? I ask all this stuff because the local homebrew supply doesn't always have the time to schmooze and Papazian, while a great resource, doesn't always address specifics. Thanks in advance for your time and patience.... Dean Return to table of contents
From: Michael_Evans at FRB-MAIN-2.CCMAIL.CompuServe.COM Date: 01 Jul 96 19:05:19 EDT Subject: Boiling wort in a pressure cooker, Crystal Budweiss clone Has anyone ever boiled their wort in a pressure cooker. Granted, it might take a large cooker to boil all of the liquid, but since the liquid retention would be so great it seems like a good idea to try. Also, I have been looking for Crystal Budweiss in Dallas and Austin. I talked to a distributor in Dallas, and she assured me that there has not been an import of this beer to Texas in a couple of months. Several retailers told me that it comes in small quantities with a high demand (because it is truly superb). Personally, I have not had the pleasure of tasting Crystal. Now that it is extremely difficult to find in Texas, my expectations are being pumped way up. Can anyone critique the beer for me? I would also like to find a clone, if it is as good as people tell me. Mike Dallas - ------------------------------ Return to table of contents
From: Jeremy Bergsman <jeremybb at leland.stanford.edu> Date: Mon, 01 Jul 1996 15:47:51 -0800 Subject: Ancient Yeast DNA, taste Al writes about the pharoh beer: =========== I saw a program about this beer on either Discovery or TLC. Clearly, the [snip] Duh! I thought they were going to implant some DNA they found in some sediment in an old jar, but no... they simply used modern ale yeast and [snip] On a bright note, they said that their research was continuing. Perhaps they are going to try to get some yeast DNA and implant into modern yeast? I hope so... *then* I'll be ready to try this ancient beer. ======== I would still save my money. Jurassic Park is not yet reality. The number of genes even in something as "simple" as our friend S. cerevisiae is very large. Just finding DNA and slapping it in there isn't likely to do much. They would either need to find a complete genome (seems unlikely to me) or swap out genes from modern yeast with whatever they could clone out of the old DNA, which would likely be very incomplete. ======== Regarding what the tongue can sense, Lubert Stryer said in a course on signal transduction he taught here last year that he felt that the 4 flavor idea was clearly wrong and that if that research had been done in France and not Germany that the number would be much larger :). I'll see if I can find any references to work that shows recent work on this. - -- Jeremy Bergsman jeremybb at leland.stanford.edu http://www-leland.stanford.edu/~jeremybb Return to table of contents
From: "CHUCK HUDSON, ER LAB 3-2865" <CHUDSON at mozart.unm.edu> Date: Mon, 1 Jul 1996 17:54:21 -0600 (MDT) Subject: RE: Will this make it??? 5th try I use a two stage set up all the time here in New Mexico in mine I have a 10 foot coil of 3/8 inch copper in a 3 gallon plastic bucket which I fill with water and freeze over night in our chest freezer. On brewing day I take it out hook up the lines and let her rip. Just be very sure that before you freeze it all of the water is out! Chuck chudson at mozart.unm.edu Return to table of contents
From: John Wilkinson <jwilkins at imtn.tpd.dsccc.com> Date: Mon, 1 Jul 1996 19:05:33 -0500 Subject: Igloo mash tun Recently Al Korzonas mentioned that the Igloo cooler was not rated for hot liquids and might distort with heat. I use an Igloo 10 gallon cylindrical cooler for a mash tun and have had no problems whatsoever. It does not show any signs of distress over the hot water I have poured into it so far. I generally pre-heat it with 10 gallons of ~140 F water then mash in it. I have done 10+ batches in it so far with no problems. John Wilkinson Return to table of contents
From: Kyle R Roberson <roberson at beta.tricity.wsu.edu> Date: Mon, 1 Jul 1996 17:45:46 -0700 (PDT) Subject: misread As several people have pointed out, 1.5e7 is the same as 16e6. Brain read e9, even though I was typing e7. Point about specifying ml of WHAT is still valid, I think. Obviously, I can still screw it up, and I've been using sci-notation for 30 years (3e1). Kyle Return to table of contents
From: Charlie Scandrett <merino at buggs.cynergy.com.au> Date: Tue, 2 Jul 1996 11:05:30 +1000 (EST) Subject: Hot O2 or not to O2? post#2 Al Korzonas writes, >Consider that in most commercial lauter tuns the sparge water falls >a good one to four feet. What keeps this water from picking up oxygen >during the sprinkling? My intuition tells me it's the water vapour. It would have to be the case in a closed container. The heated initial air would rise out and be replaced by water vapour. I can think of no process that would allow air in. ` David Burley posted, >Charlie Sandrett is going to do some work on HSA. Is there a t*st procedure >available to t*st for HSA? Good luck Charlie we will look forward to your >results. I have it on good authority that he is not! Well, not intentionally. I think he is trying to minimise it in a controlled, repeatable environment so that he has a control beer with a constant redox potential (rH potential) everytime he makes a batch. He will then get on with his dream of using new technology to produce deoxygenated kegs with no yeast and <0.01 ppm O2 and press gang some judges into drinking it every month for as long as it takes. My prediction (based on Greg Organ's work on beers at 0.15 ppm O2) is 6-9 months aroma survival, 3 years without staling flavours! The very matured pils should be a new taste sensation, never experienced before. De Clerck gave up on simple electrometric methods of determining the redox (oxidation-reduction = rH) potential of fresh beer in 1937. The first accepted method was Grey and Stone (1939) who measured the time taken to reduce 2,6-dichlorophenolindophenol (if you can still pronounce it after 5 beers, its not oxidized!) to 80% discolouration. This is called the Indicator Time Test (ITT) and to be accurate, needs colour measuring equipment like a spectrophotometer. Although labs have refined this test, the in-process brewery floor control test in Australia goes something like this. *Everything is done at 20C*. A standardized daily batch of dyestuff is made up in dioxine. 20ml of beer is added to 0.5 ml dye solution, stopwatch started, and a bit transferred into a spectrophotometer cell. Another cell has control beer in it. A plot of the optical density change against time is made for light at 525nm wavelength. The constant density of the control beer (~0.015)is added to the known density of 80% discoloured pure 2,6-dichloro..etc..etc.(= 0.220) to create a target optical density of ~0.235. The time taken to reach this 80% discolouration point is the ITT value of the beer and correlates well with its shelf life. Shorter ITT = longer shelf life. (*all other things being equal*) You are really measuring the redox state of the polyphenols and mellanoids, this is a sort of HSA test. In order to test the shelf life's dependancy on "other things", in particular DO (dissolved oxygen) levels, I have to be able to control temperature, excess lipid levels and the rH (minimum HSA) value of my test beer. In this process I will discover the optimum techniques for doing this on a small scale. Even if the above test method is useless for homebrewers, the optimum flavour stability techniques should be of interest. (even for HBD's "Keith, the Morovian swearing bear," who doesn't hold scientific method in high regard. Australians will know who I mean...) Charlie (Brisbane, Australia) Return to table of contents
From: Steve Alexander <stevea at clv.mcd.mot.com> Date: Mon, 1 Jul 1996 21:03:23 -0400 Subject: Enzymes - (sources) And Al K. write more ... >Steve writes (amidst some very interesting enzyme information): >>This relation falls out of the Michaelis-Menten kinetics model, and should >>appear in chapter one of any textbook. ... >Could you suggest a few titles? 'Enzyme Technology', M.F.Chaplin & C.Bucke, Cambridge Univ. press 'Industrial Enzymolgy, The application of Enzymes in Industry', Tony Godfrey & Jon Reichelt, Macmillen Publ.Ltd, 1983 'The Enzymes' Vol 1, Boyer, Lardy & Myrback, Academic Press, 1960-1963. 'Enzymes in Food Processing', edited by Gerald Reed, Academic Press,1975 There's a really good description in a two volume set called 'Enzyme Handbook', 1968, but I don't have publ. info. one of the original works is 'Enzymes',Haldane, J.B.S., Longmans: London 1930 Books I haven't accessed but seem likely are: 'Enzyme Kinetics: From Diastase to Multi-Enzyme Systems', Arthur R.Schultz 'Enzyme Dynamics and Regulation', P.Boon Chock 'Food Enzymology', Vol 1, P.F.Fox There are a lot of titles under the subject of 'bioreactor' and 'enzymology' that will answer your question. Most anything with 'enzyme' and 'kinetics' will answer your question. >Regarding the inhibition of beta amylase by glucose and maltose, it sounds >as if there are two factors in competition here. While the initial 'Competitive' inhibition is a very specific term that indicates that the inhibitor combines with the enzyme (not the substrate) to inhibit the reaction. I have documentation that maltose competitively inhibits beta-amylase. I believe that glucose also competitively inhibits, but I have no documentation for this. It could 'non-competitively' inhibit by forming an enzyme-substrate-inhibitor complex - but this seems to me unlikely. It could also 'uncompetitively' inhibit by the inhibitor complexing with the substrate alone - again unlikely IMO. >saccharification rate will be higher for a stiff (thick) mash, the inhibition >will also be higher as the reaction progresses. I would therefore assume >that there is a mash stiffness which is optimal, one in which the former >factor is maximized while minimizing the latter. Correct? Furthermore, >would it be fair to assume that the conversion rate may also be increased >by starting with a stiff mash and then diluting it as the conversion >progresses? Despite the loss of beta amylase from the heat, is it >possible that the water added in step infusions could not only be increasing >the temperture from say 148F up to 158F, but also helping increase beta >amylase conversion by diluting the mash and thereby decreasing the inhibitory >effect of high maltose/glucose concentrations? Competitive inhibition effects can be overcome by increasing the amount of substrate compared w/ the amount of inhibitor. This means adding more starch toward the end of the mash, which is counterproductive. Adding more water decreases the rate of the reaction by making it less probably that the enzymes and starch will collide and complex. It will generally also decrease the enzyme stability as you well know. By adding water the ratio of substrate to inhibitor remain the same and it would appear that the ratio of enzyme-substrate (productive) complexes to the number of enzyme-inhibitor (unproductive) complexes remains the same. Adding water should slow, not speed the reaction because we are not diluting the inhibitors w/ respect to the substrate. If the inhibition is non-competitive or uncompetitive then adding more substrate won't eliminate the inhibition. Only decreasing the amount of inhibitor will help, since these modes are concerned with enzyme-inhibitor complexes. Apparently as long as we wish to arrive at the same final inhibitor (maltose+glucose) to substrate (starch) ratio, we will suffer the same level of inhibition. My partly substantiated guess based on what I read is that as long as you end up with enough water to hydrolyse the reaction freely, and keep enzymes and substrate in free association, then the thicker the mash, the quicker you get to mash-out. The inhibitor concentration is a problem we just have to continue living with unless we come up with a clever way to selectively move maltose and glucose into the boiler while the mash continues. Hmmm - the molecular sparger - maybe an RO filter capable of selectively passing small sugars, but not proteins or starches ? >>Specific activity does not typically drop with increasing temperature as >>some contributors suggest. > >I don't recall anyone suggesting this. Actually David Burley wrote ... ><sugar. SO, at the high end ( 155-158) of the saccarification region( 145-160 ><F), even though the rate of saccrification (at a constant enzyme ><concentration), ><is higher, the stability of the enzyme is lower and is disappearing faster. and Jim Busch responds ... >What is being reduced is the activity of Beta Amylase which controls >fermentability (more rest at 145F increases maltose production). Enzyme Activity is a term that needs to be carefully examined in each context. I admit that Jim isn't saying this, but his use of the term 'activity' is, or should be, confusing to a novice. Most of the bell shaped or blip shaped curves that appear in brewing literature and designate activity vs temperature must be taken with a grain of salt. The amount of product that a particular enzyme can produce at a particular temperature over a given substantial amount of time is temperature limited because the enzymes deteriorate over that period of time, not because the enzyme molecules individually catalyse more slowly at higher temperatures. As the period of time approaches zero, which measures the initial rate of catalysis, then the curve should cease to fall off with increasing temperatures. Instead we would expect to see a nearly exponentially increasing rate of initial activity vs temperature. The high temperature drop off in long-period activity is really an entirely different effect caused by denaturation of enzymes, which rate also nearly exponentially increases with temperature. It's easy to experimentally reproduce the bell shaped curves by mashing for say 30' at several different temperatures and checking the result. Unfortunately it's very hard to use this curve to predict results that occur over different periods of time, since the curve is really the combination of two different effects; specific activity and denaturation rate. > The bottom line to the brewer is the >important part: > >* do most of your starch conversion at 148F and you'll get a > more fermentable wort (low FG), and > >* do most of your starch conversion at 158F and you'll get a > less fermentable wort (high FG). I think we're all in sync with this fact now. Steve Alexander Return to table of contents
From: BrewIPA at aol.com Date: Mon, 1 Jul 1996 22:35:40 -0400 Subject: BUZZ-Off results This year's BUZZ-Off competition was highly successful. Over 320 entries were tasted and evaluated in the largest homebrew competition in the east. If you entered this competition please note we will be mailing your scoresheets along with the scores for every beer entered. We are estimating a mailing date of July 5. We hope everyone who entered is able to benefit from our expert judge panel's comments on your beer and further hope you will be able to use that feedback to make even better beer. Listed below are the names of the brewers who were able to rise to the top in each of the different ribbon categories: Strong Ales 1st Doug Buddle 2nd Keith Houck 3rd Rich Rosowski Belgian A;es 1 Ted Hull 2 Dave Houseman 3 Dave Houseman Mild & Brown Ales 1 Jason Motz 2 Charles Green 3 Joe Puksta English Pale Ales 1 Charles Green 2 Bruce Daniels 3 Mike Scully American Pale Ales 1 Anthony Gromek 2 John Jacobs 3 Marc Schankwerter Stouts 1 Rich Rosowski 2 Erich Marriott 3 Bill Muller Porters 1 Rick Derr 2 Peter Campagna 3 Lisa Hudock Mixed Ale/Lager 1 Alan Folsom 2 Chuck Hanning 3 Ed & Carol Wolfe Fruit 1 Jack Hauler 2 Pat Bannon 3 Paul Lefebvre Spice, Smoke and Special 1 Cliff Rice 2 Marc Schankwerter 3 Rex Saffer Mead 1 Grover Vos 2 Barry DeLapp 3 Fred Hardy Dark Lager 1 Richard Brill 2 Alan Folsom 3 Jim McHale Light Lager 1 Mike Hansen 2 Curt Speaker 3 Paul Lefebvre English Bitters 1 Charles Schmidt 2 Dave Houseman 3 Ted Hull Wheat Beer 1 Ed & Carol Wolfe 2 Kurt Black 3 Mark Stevens Cider 1 Bob Walters 2 Bob Walters Return to table of contents
From: "Sharon A. Ritter" <102446.3717 at CompuServe.COM> Date: 01 Jul 96 23:01:32 EDT Subject: Re: HSA - Chill to 35 F >From: Edward J. Steinkamp >Does anyone know the maximum temperature differential yeast can >take? Dave Miller answered a similar question in the March/April edition of Brewing Techniques (Q&A With the Troubleshooter). His source (Dr. Joseph Power of the Siebel Institute) indicates that the maximum rapid temperature drop that a yeast can handle is about 18F (10C). Yeast thermal shock going from colder to warmer is not a problem (from the same article). >I've heard the Wyeast strains like to be pitched at around >70 F no matter what strain. Is this true? I have used Wyeast lager and ale strains and pitched them at 45-50F. I've always had complete and active fermentations. Of course I've held fermentation temps for lagers at 45-50F, or allowed temps to rise and them stablized them for ale strains. A dedicated brewing refrigerator with thermostat is nice to have. Dan Ritter in Grangeville, Idaho 102446.3717 at compuserve.com Return to table of contents
From: hollen at vigra.com Date: Mon, 1 Jul 96 20:04:02 PDT Subject: Re: Radiator hose for RIMS >>>>> "Tim" == Tim Martin <TimM at southwest.cc.nc.us> writes: Tim> I am not a RIMS brewer but one day while mowing the lawn it Tim> came to me, why can't those RIMS brewers use a radiator Tim> hose to connect their tanks and pumps together. Listen Tim> before you make that face...A one inch dia. hose cost about Tim> a dollar per foot at the local auto parts store, comes in any Tim> length you need and a wide range of diameters and will Tim> withstand tremendous heat, there. While all of that may be true, I know from experience that radiator hose is not good for RIMS. I use some as a hot water hose for non-brewing uses and the taste that gets leached out from it is not good. Would not want to use it for RIMS. dion - -- Dion Hollenbeck (619)597-7080x164 Email: hollen at vigra.com Sr. Software Engineer - Vigra Div. of Visicom Labs San Diego, California Return to table of contents
From: jfrodriguez at jfrodriguez.seanet.com (Joe or Sue Rodriguez) Date: Mon, 1 Jul 1996 20:17:43 -0600 Subject: How to clean up a boilover? I did the unthinkable and took my eyes away from a perfectly good boil only to have it boil over. Needless to say it made a mess that's been difficult to cleanup. Does anyone have a good cleaning product that can get the carmelized wort off my cooking stove? Sue or Joe Rodriguez jfrodriguez at jfrodriguez.seanet.com Return to table of contents
From: The GasFamily <gasman at tscnet.com> Date: Mon, 1 Jul 1996 22:04:48 -0700 Subject: Three stage cooler John Varady writes - This weekend I am going to use a short piece of copper coil (3') in ice water to do the same. Has anyone tried such a two stage chiller setup? When I first made up my standard counterflow chiller I used the extra 3/8" copper tubing as an immersion chiller _and_ as a terminal ice bath. My cooling water temps were acceptable but I thought I would try it out anyway. I'm back to just using the CC chiller because the benefit didn't justify the extra setup and the slower flow. I used the cooling water output from the CC chiller to run through the immersion chiller on the theory that the water could extract a tad more heat - it did - I had warm/hot water for cleanup. Using just the CC chiller the water isn't as hot since it has less time to equilibrate with the hottest portion of the wort. Mike Gasman Return to table of contents