HOMEBREW Digest #2579 Wed 10 December 1997

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  AHA Vienna and Oktoberfest Guidelines (George De Piro)
  Boil time for flavor hops? ("C&S Peterson")
  Vicky Rowe's Non-fermenting Cyser (Mallett,Mark)
  Beta amylase/sparge temp (Al Korzonas)
  beta glucans; Noche Bueno (George J Fix)
  yeast dying slowly ("Taber, Bruce")
  Clinitest and Noonan (Al Korzonas)
  Licorice Stout ("Ellery.Samuels")
  Rogue Pacman Yeast (neumbg73)
  recipe ownership ("Bryan L. Gros")
  Iodine Test, Part 1 ("David R. Burley")
  Iodine Test Part 2 ("David R. Burley")
  Clinitest ("David R. Burley")
  Iodine Test Part 3 ("David R. Burley")
  Old Homebrew ("Rosenzweig,Steve")
  beer to distill (AlannnnT)
  Stainless fermentors (AlannnnT)
  Grain Mills ("Capt. Marc Battreall")
  Conical Fermenters ("Michael T. Bell")
  Courage, it's what your right hand is for.... (Chasman)
  Larry O'Mahoney,Temp Correction,Alcohol estimation ("David R. Burley")
  Simple way to start siphon (Scott Howard)
  Co2 Pressure  (Matt Arnold) (Andrew Quinzani)
  Clinitest ("Raymond Estrella")

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---------------------------------------------------------------------- Date: Fri, 5 Dec 1997 12:37:20 -0800 From: George_De_Piro at berlex.com (George De Piro) Subject: AHA Vienna and Oktoberfest Guidelines Hi all, Just a quick AHA Style Guidelines comment. If you don't care about the AHA, style guidelines, or beer judging, page down now. Have many of you read the latest guidelines for Vienna and Oktoberfest beers? I have, and have to ask one question: why are there two separate styles for these beers? The new guidelines for Oktoberfest include such low starting gravities that there is no appreciable difference from Vienna lager (Vienna: 1.048-1.056; O'fest: 1.050-1.056). What happened to allowing for traditionally accurate Oktoberfest beers with OG of around 1.062? The AHA doesn't acknowledge them anymore? Just because many commercial brewers here and abroad produce Oktoberfests that are essentially Viennas is no reason to eliminate the higher gravity, traditional Oktoberfest from the guidelines. Bizzarely, the new guidelines also allow for some fruity character in Oktoberfest beer. Why? Since when are estery lagers OK? Especially German lagers! I could *maybe* see the point that a high-gravity Oktoberfest might ferment a bit fruity, but any brewer producing an estery 1.050 lager is doing something wrong. Using these new guidelines, the AHA NHC gold medal-winning Oktoberfest that I brewed in 1996 would have been panned for being too big for style (its OG was 1.062). I guess I'll have to change my recipe (note extreme sarcasm). I did write the AHA about this, and have been ignored. I don't expect immediate change, but acknowledgment of this flaw would be nice. Have fun! George De Piro (Nyack, NY) Return to table of contents
Date: Fri, 5 Dec 97 17:56:44 UT From: "C&S Peterson" <CNS_PETERSON at classic.msn.com> Subject: Boil time for flavor hops? HBDers - Since I've just begun brewing beer for the season, I had some early results and a quick question for you hop gurus out there. Two of my brews this year have come in with a slightly objectionable (to me at least) hop flavor profile. I think it can be described as "spicy" or "piney". While I know some hop-heads like this sort of flavor, I prefer balanced beers. Both beers has substantial flavor hops added in the last 15 to 5 minutes of brewing. So, I figure this *objectionable* flavor profile is due to: A. simply adding too much hop (about 2 oz per 12 ga of Sazz pellets for a 1.051 American wheat and about 1oz of Williamette/Goldings for a 1.053 APA) B. adding the flavor hops too close to knock-out The only reason I consider "B" a possibility is that from some old brewing log notes I observed that a got "smoother" hop flavors if the flavor hops were boiled at least 15 minutes. I also checked the latest Zymurgy special issue. Most of the gold medal winners used 30 to 20 minute flavor boils; very few used less than 15 -- ignoring of course the 1 minute or steep additions for aroma. I also thumbed through the special issue to see if there was any wisdom on how long a flavor hop should be boiled. Couldn't find anything specific, but suggestions for anything less than 30. Given that there is extensive numerical analysis for bitterness, what is the common wisdom on hop flavors? Will flavor hops added closer to knockout favor any specific hop oils? Any guidelines from hop experts on this issue? Chas Peterson Laytonsville, Md Return to table of contents
Date: 05 Dec 97 13:36:42 GMT From: mallem60 at wales.bbc.co.uk (Mallett,Mark) Subject: Vicky Rowe's Non-fermenting Cyser Maybe the apple juice was not only pasteurised, but also contained a preservative, thus inhibiting fermentation. Return to table of contents
Date: Fri, 5 Dec 1997 12:36:23 -0600 (CST) From: Al Korzonas <korz at xnet.com> Subject: Beta amylase/sparge temp Kent writes: >Beta amylase activity is *zero* after 30 minutes at 150F. Unfortunately >I don't have the graphs for alpha with me, but it is safe to assume >that there isn't any enzyme activity left by the time you get to >mashout or sparge. According to Malting and Brewing Science (second edition, volume 1, p.291): "Beta-amylase is destroyed in mashes in 40-60 minutes at 65C (149F). The alpha-amylase activity declines at 67C (153F), the last activity disappearing in about 2 hr." As I said before, however, under ideal conditions (proper grind and pH) most of the conversion will indeed take place within 30 minutes, but for most of us, I don't recommend anything short of 1 hour and personally, I mash for 1 hour when I'm mashing at or above 155F and for 1.5 hours when I'm mashing below 155F. Kent also claimed that there is little difference between sparging with 150F water and 170F water. I would tend to disagree. Besides my oft quoted research done by Rob Reed, Malting and Brewing Science comments on sparge temperature also (p.293). I'll paraphrase... First runnings can be taken at the last rest temperature (for example at 65C (149F) or after heating to approximately 75C (167F). Sparging is done using water that is hotter than the mash, e.g. 75-80C (167-176F). The higher temperature reduces wort viscosity and results in a faster runoff, extracts soluble compounds more quickly, and results in an almost complete deactivation of the enzymes. Now, I've posted before, that I cannot come up with a scenario in which it is important to denature the enzymes. *Please* see my previous posts on this before challenging this assertion. Al. Al Korzonas, Palos Hills, IL korz at xnet.com My new website (still under construction, but up-and-running): http://www.brewinfo.com/brewinfo/ Return to table of contents
Date: Fri, 5 Dec 97 13:02:07 -0600 From: gjfix at utamat.uta.edu (George J Fix) Subject: beta glucans; Noche Bueno In a past issue of HBD I remarked that I observed a definite increase in gravity during a low temperature rest at 40C. Someone whose name escapes me (I recently lost a hard disc and with it old HBD files) asserted that the increase in density was due to beta-glucans. This can not be true. The last time I checked, beta-gucans were under 1% of the total wort carbohydrates. Meilgaard in his classic article on wort composition in the Practical Brewer puts their level at 0.20%-0.25% by weight. The exotic sugars are present at even lower concentrations. Thus to a reasonable degree of accuracy, gravity (as mesured by the refractive index or for that fact by a hydrometer) is a measure of the dextrins and fermentable sugars present. I agree with Barry Browne that the iodine test is not a perfect measure of "conversion" (whatever that means), and for this reason I find the forced fermentation test recently mentioned by Louis Bontham to be the most reliable guide to fermentability. Pat Babcock and Mark Weaver ask about a metallic taste in Noche Bueno. It is my belief that it is an oxidative effect, and it is particulary bad this year. Friends who tasted the beer in Mexico City right after it was released report as Kenny Schwartz did, i.e., metallic tones were not present. For those of us who do not live near the border and who are not planning a trip south anytime soon, I suggest we forget the commercial product and brew our own versions! Cheers, George Fix P.S. Because of my hard disc problems my e-mail correspondence is messed up. I hope to get this resolved by early next week. Return to table of contents
Date: Fri, 5 Dec 1997 13:54:00 -0500 From: "Taber, Bruce" <Bruce.Taber at nrc.ca> Subject: yeast dying slowly I have been using Wyeast #1098 (British Ale) for a couple of years. I buy a pack and step it up to make 4 cups of starter which I split into 4 and store in the fridge so that my next 4 batches will all use second generation yeast. The last two batches of ale (OG 1.052) started and fermented great (<6hr. lag) but stopped at 1.024. The first two batches from the same Wyeast pack worked fine. The yeast for batch #3 was in my fridge for 3 months, for batch #4 it was 4 months. I have previously kept yeast this way in the fridge for up to 8 months with no problems. I ended up pitching a dry yeast to restart the ferment and it finished fine and tasted fine (no infection). It was as if the yeast was slowly dying of old age. Has anyone seen this before? The strange thing is I made a starter so there should have been lots of healthy 3rd generation yeast to do the work. My procedures such as sanitation and oxidation were the same as always. I've got lots of batches under my belt (figuratively and literally) and I've never seen this before. A related question. Since I pitched an Edme dry yeast half way through the ferment, which yeast do you think will have the most effect on flavor? In other words, which half of the ferment will produce most of the flavor characteristics, the top half (1.052 - 1.024) or the bottom half (1.024 - 1.012) ? My early tastings seem to indicate that the late addition of dry yeast definitely had an effect on the flavor. Bruce Taber Almonte, Ont. Canada Return to table of contents
Date: Fri, 5 Dec 1997 13:03:15 -0600 (CST) From: Al Korzonas <korz at xnet.com> Subject: Clinitest and Noonan Spencer writes: >I was reading Noonan's New Brewing Lager Beers the other day, and >found the statement (paraphrased slightly) that "fermentation is >finished when the reducing sugar content is 2% or less." So a >reducing sugar content of 1%, as indicated by the Clinitest kit, >probably indicates complete fermentation. I consider Noonan to be one of the most knowledgable Americans on decoction brewing, but his book contains a lot of errors when it comes to the science behind the brewing. One fine example is his statement that oxygen dissolves more easily in hot wort than cold! Presuming that Dave is right about Clinitest reading 1/4% sugar in most of his beers when they are finished, then 1% as Noonan suggests is very likely to cause gushers. Please note that I have never said that the Clinitest *won't* work in predicting the true final end of fermentation, only that I was skeptical that it was consistent based on AJ's post that dextrins will cause a reaction. I also said that using the Clinitest was (in my opinion) not accurate enough to be used for reducing the priming sugar in batches that were not quite done fermenting (too much variablity). Incidentally, unless you are using something as accurate as a RIMS and are making exactly the same recipe many times, I don't even think that a hydrometer is accurate enough to predict how much priming sugar to subtract when trying to bottle/keg a batch before it is truly done fermenting. You simply cannot predict the FG accurately enough in most systems and most homebrewers rarely make the same recipe enough times. Heck, FG can vary with starter size, aeration/oxygnation levels, and fermentation temperature! Even the RIMS brewers may not have enough control over these variables. The pros can do it, but most (all?) of them still use special valves that restrict the CO2 pressure in the conditioning tanks. Al. Al Korzonas, Palos Hills, IL korz at xnet.com My new website (still under construction, but up-and-running): http://www.brewinfo.com/brewinfo/ Return to table of contents
Date: Fri, 5 Bec 97 15:06:01 EDT From: "Ellery.Samuels" <esamuel at mvsb.nycenet.edu> Subject: Licorice Stout Hi All, Would like to brew a stout using licorice. Does anyone have suggestions as to how to do this without getting an overpowering taste and/or aroma of licorice? Thanx - Ellery Return to table of contents
Date: Fri, 05 Dec 1997 14:57:00 -0400 (EDT) From: neumbg73 at snyoneva.cc.oneonta.edu Subject: Rogue Pacman Yeast ***Begin, my $.02*** Hello, a while ago the subject of reculturing Rogue's Pacman yeast from their bottles was discussed. I just thought I'd add to the thread with my results from brewing with that yeast. Back in September I brewed a choclate porter with an OG of about 1.080. I very sucessfully recultured the yeast from a 12 oz bottle of Rogue Mocha Porter that had been in my basement since the previous May, and stepped up the culture to about 20 oz.The first few days of fermentation were very vigorous. They're very hard working little beasts indeed. Within 5 days the OG fell to 1.015. It's been aver two months in the bottle and the end product is a very smooth, drinkable porter, and is also the fastest dissappearing beer I've ever brewed. I'm almost out! Time to brew more. The same strain of yeast is also chugging away with a pumpkin ale, right now. *** End my $.02 *** (thanks) -bernie kb2ebe "Typhoon Rips Through Cemetery - Hundreds Dead" Return to table of contents
Date: Fri, 05 Dec 1997 12:13:47 -0800 From: "Bryan L. Gros" <gros at bigfoot.com> Subject: recipe ownership I'm glad Louis posted about the fact that recipes themselves can't be copyrighted. >From a brewer's perspective, a recipe is only the beginning for trying to produce the beer yourself. Although corporate types probably don't understand, it is a very difficult task to reproduce someone's beer. We all now have the recipe for Rob Moline's Gold Medal winning barleywine, but if we all brewed a beer with that recipe, we'd all be serving a different beer (albeit with some similarities). All brewpubs have access to the same grains and hops, but all of us have our favorite beers and our less favorite beers. - Bryan gros at bigfoot.com http://www.dnai.com/~thor/dboard/index.htm Return to table of contents
Date: Fri, 5 Dec 1997 15:06:30 -0500 From: "David R. Burley" <Dave_Burley at compuserve.com> Subject: Iodine Test, Part 1 Brewsters: All I can say to Barry Browne's comparison of the iodine test and = refractive index as a way to measure conversion is WOW! = Thanks a lot for publishing it. His results seem to confirm my past admonitions that the "standard" iodine test is nearly useless as a measure of conversion for infusion mashes, and my flat-out dismissal of C. Papazian's suggestion that a conversion is complete in a few minutes, based on the iodine test. (at least as is commonly read - the disappearance of the black reaction) Barry, I'd be interested to see if my version of this test - boil the sample before you do the test - is a better way to do it based on you ability to use this additional diffraction technique. There are reasons why the iodine test is lacking: 1)the major one is the iodine test is strongly responsive (black) towards amylose ( about 20-25% of the starch) which disappears rapidly and weakly responsive ( mahogany to light purple) to amylopectin (about 75-80% of the starch) which is slower to disappear. ( see below for details) 2) in an infusion mash not all of the starch may be available immediately to the solution since it may be physically trapped and why I boil to release it. Next time you do this comparison, please include this into your test regime. It won't take much effort. Also, if you boil immediately it should stop the enzyme reactions completely. I do the test this way: Take a ~10 milliliter mash sample which contains the grain, place it in the microwave and boil it briefly, cool slightly and then run the test. I know AlK's objections in the past has been about "hidden" starch being released this way, but I don't believe this objection is well-founded, relative to having an easy test which is truly a measure of remaining starch. Actually it is this difficult to react = portion that acts as an indicator for the amylopectin still remaining, I guess. As I have said in the past, I believe the iodine test works for decoction batches pretty well because some of the grain is boiled and starch is released. This may explain the reason for the acceptance of this test by the industry. I concur that it is necessary to hold the saccharification step 90 minutes or so to get complete conversion. End of part 1. See parts 2 and 3 please. Keep on brewin' Dave Burley Kinnelon, NJ 07405 103164.3202 at compuserve.com Dave_Burley at compuserve.com = Voice e-mail OK = Return to table of contents
Date: Fri, 5 Dec 1997 15:06:27 -0500 From: "David R. Burley" <Dave_Burley at compuserve.com> Subject: Iodine Test Part 2 Brewsters: Brewsters: Part 2 = After that summary of my conclusions on the reason the iodine test does/n't work and a little positioning of the importance of Barry Browne's results in part 1,my response to Barry Browne's request follows: > I'd like to discuss how we brewers decide when mash = conversion is = > complete. I have reason to doubt the validity of the oft-quoted = iodine = > test for starch and am looking to the biochemists out there to explain = > more clearly the specific iodine-starch reactions that cause color changes = > in the mash samples. = = I'm not a *bio*chemist by education, but I am a chemist. An old,old book Noller (1957) - Chemistry of Organic Compounds" p 397 says: "When starch is heated in water, the granules swell greatly and a colloidal suspension is produced. This dispersion = has been separated into two components..... = The microcrystalline fraction known as *amylose* and..... an amorphous fraction known as *amylopectin*...... = Most starches contain amylose in the ratio of from 1:4 to 1:5. .. =2EThe two fractions differ markedly in their chemical properties... *pure* amylose is only sparingly soluble in hot water and = reprecipitates..(pure -DRB).Amylopectin dissolves readily in water and the solution does not gel... Solutions of native starches = gel rapidly and precipitate slowly. .Apparently the amylopectin acts as a protective colloid for the amylose... The typical blue color reaction of starch with iodine is due to the *amylose* portion which absorbs 18 to 20 percent of its weight in iodine....The blue product appears to be an inclusion compound = which fits into the open spaces of a helix of C6 units that constitute the amylose molecule. ( and, I conclude, the reason for the very specific nature of this [perhaps charge-transfer] reaction -DRB)....= =2E. *Amylopectin* gives a red to purple color and absorbs only 0.5 to 0.8 percent of iodine.... = Both fractions give only glucose on complete hydrolysis by acids..... Two groups of starch splitting enzymes have been recognized for some time, the alpha and beta amylases..... both are 1,4 alpha -glucosidases. They differ in that alpha-amylase = hydrolyses the linkages randomly, whereas the beta-amylase attacks only the second link from the non-reducing end of a chain and liberates maltose. Amylose is hydrolysed to maltose to the extent of 70 percent by pure beta-amylase. In 1952 it was found that if another enzyme called Z-enzyme is present, hydrolysis to maltose proceeds to completion...... P398 Amylopectin is hydrolysed to the extent of only about 50 percent by beta-amylase with or without the presence of Z-enzyme, the remainder being a high-molecular weight product known as "limit-dextrin". However, beta-amylase in conjunction = with another enzyme known as R-enzyme , a 1,6 alpha-glucosidase, brings about complete hydrolysis." A newer book "Principles of Biochemistry" Lehninger, et al (1993, 2nd ed) is silent on this iodine reaction. But says on p 308: "Starch consists of two types of glucose polymers, *amylose* and *amylopectin.* The former consists of long, unbranched chains ( which I guess explains why it crystallizes readily -DRB) of D-glucose units connected by [alpha-1to 4] linkages. Such chains vary in molecular weight from a few thousand to 500,000. Amylopectin also has a high molecular weight (up to 1 million), but is highly branched (which I guess explains why it doesn't crystallize -DRB). The glycosidic linkages = joining successive glucose residues in amylopectin chains are [alpha-1 to 4], but the branch points, occurring every 24 to 30 residues are [alpha-1 to 6] linkages. (which explains = Noller's observation about the necessity to have = alpha-1,6 glucosidases for complete conversion - DRB)" End of part 2. See Part 3 for a discussion of your results. Keep on brewin' Dave Burley Kinnelon, NJ 07405 103164.3202 at compuserve.com Dave_Burley at compuserve.com = Voice e-mail OK = Return to table of contents
Date: Fri, 5 Dec 1997 15:06:18 -0500 From: "David R. Burley" <Dave_Burley at compuserve.com> Subject: Clinitest Brewsters: Spencer Thomas says: >I was reading Noonan's New Brewing Lager Beers the other day , and >found the statement (paraphrased slightly) that "fermentation is >finished when the reducing sugar content is 2% or less." So a >reducing sugar content of 1%, as indicated by the Clinitest kit, >probably indicates complete fermentation. I somehow missed this reference, but admit to not reading his second edition thoroughly. If this is actually a fair paraphrase of what he meant, then he is either wrong or he means that at less than 2% it's time to move the beer out of the primary fermenter and into the secondary fermenter. Giving him the benefit of the doubt, I'll assume the latter. My use of Clinitest in beer came about when I realized it was perhaps more useful in beer-making than winemaking where I first used it some three decades ago. In all these decades, I have never had a beer finish above 1/4 % to my best recollection. It is true that the active primary fermentation is ceased by = about 2% glucose by Clinitest, but the sugar level continues to decrease slowly over several days to anywhere from a <1/4% reading to 0%. This is how I would define "finished". Keep on brewin' Dave Burley Kinnelon, NJ 07405 103164.3202 at compuserve.com Dave_Burley at compuserve.com = Voice e-mail OK = Return to table of contents
Date: Fri, 5 Dec 1997 15:06:23 -0500 From: "David R. Burley" <Dave_Burley at compuserve.com> Subject: Iodine Test Part 3 Brewsters: Part 3 of the discussion of Barry Browne's results. Barry Browne says: = > I have doubted the iodine test for several years So have I for two reasons: = 1) it is weakly responsive to 75 to 80% of the starch (amylopectin) and = 2) Not all of the starch may be available physically for the reaction. >. Routinely, and regardless of base malt type, I do not see = > a "plateau"ing of mash refraction index, which to me would mean full = > conversion, until about 2 hours into the saccharification rest phase. I agree with this, based on my iodine test method and lots of experience. > To = > provide some data to back up this statement for the HBD, I monitored = a = > recent mash with both methods; the data follows. = > Dough in to stabilize at 40C, rest for 30 min You missed an opportunity to confirm George Fix's observation that the refractive index increases in the 40C region. I interpret this as the beta glucans dissolving, but would have = liked some diffraction readings during this period. Weyerman's Pilsner is reputed to be (unusually?) highly modified for a Pilsner and they say it can be used in a single infusion mash to make pale ales according to what I have been told by another brewer . I have never tried it in this way, but this may be the source of George Fix's position on all modern Pilsner malts being highly modified. Obviously, I am still struggling to understand his position without the information base he may have. > Increase T to 60C over 25 min (anyone think this is too fast?) I normally come from 40C via 122F(50C)- 15 minutes hold to 135F (60C) - 30 minutes hold at about 2 degrees F or about the same rate. This heating rate is typical of the industry, based on what I read. Time Elapsed T(min) Mash Temp(C) Brix% Iodine Test(color) ----- ------------- ----------- ----- ----------- 10:50 0 (dough in) 40 NT NT 11:20 30 Begin to increase temp to 60C 11:45 55 60 NT NT= 12:03 73 60 13.4 ne= g. (black) I would call a *black* reaction "positive" to indicate a reaction to the presence of (amylose) starch. 12:13 83 60 14.8 neg. (dk.brn to reddish) Typical of amylopectin a "mahogany" color -again "positive" 12:23 93 66.7 (rising) 15.6 unsure but looks positive= 12:33 103 70 17.2 positive (no color change= ) Likewise, this indicates no starch by the iodine test and I would call this "negative" > All samples were replicated and were allowed to cool to ambient room temp > which fortunately was 60 F (therefore no correction required for = > refractometer). However, reactions may well have continued in your samples unless you chilled with ice immediately. Try cooling in a metal vessel ( I use a metal shot measure or SS measuring cup) in an ice bath next time > I don't allow doubt, it's too important not to be sure. I agree. Best lesson I ever learned in quantitative chemistry. >These data, which are typical of my mashing experience, Don't you find your beer somewhat dry and thin with this long, low hold? > several > interesting points. > 1. Based on Brix values, 16% more conversion takes place after the iodine = > test indicates complete conversion [(20.5-17.2)/20.5*100=3D16.1%] = Actually your test results, based on my above chemical discussion indicates that the *amylose* (black reaction) disappeared at = around 60C, but not the *amylopectin* ( pale mahogany reaction). This is not surprising since the amylopectin needs a second enzyme to complete the conversion to maltose and other intermediates and = disappears more slowly. = > 2. Most of the starch conversion has occurred at or below 60C. Not surprising, since both beta and alpha amylase are active here and this is the optimum temperature for beta-amylase as I recall and 70C (158F) is the optimum for alpha amylase. What I find = interesting is that this is below the supposedly "gelatinization" temperature of 149F oft quoted by British texts - but Andy Walsh = showed how complicated that was in his excellent contribution = a couple of weeks ago. = Of course, with this temperature scheme you will have virtually all maltose and few dextrins, since the beta amylase has a lifetime of = at least two hours at this temperature, I recall. = > Questions. = > 1. If the iodine test is accurate, as appears to be widely = accepted, what = > compounds are being produced to increase wort refractive index beyond = > indicated complete conversion? = Maltose which is converted to Glucose by yeast maltase. > 2. Are these compounds fermentable by Saccharomyces spp.? Yes >3. Since some conversion is still occurring at mashout T =3D 77C, = what T = > really does denature our beloved enzymes? = Alpha Amylase can last for quite a while at this temperature, and the major reason in my book for the mashout is to decrease the wort viscosity and increase the lauter rate. This temperature does increase the rate of reaction and kind of finishes off the = remaining carbohydrates, if any. As AlK has pointed out lots of times, this mashout temperature is not too important for removing alpha = amylase - if all the beta amylase is gone - so what? I agree if you used a long hold (90 minutes) as both he and I do. However, if you used a short, low temperature hold scheme, such a mashout might be important to your wort stability as some beta amylase might still be around and chew up the dextrin-like compounds = during the sparging step. In this case it might also improve your efficiency and change the carbohydrate profile as the alpha amylase could still be active for a short time during the sparge. I always assumed the comment about the the enzymes disappearing during mashout meant the beta amylase predominantly,since it would affect wort carbohydrate stability the most. Also, remember that enzymes are generally much more stable in mashes than isolated in a flask. = > There are more questions I (and others) could ask but I'm most interested = > in the discrepancy between the Brix plateau at 20.5% and iodine conversion = > at 17.2%. Nice job!! = > By the by, I've done the extraction efficiency calcs Extraction effciency is dependent on a lot of things, including operating in a temperature range where alpha amylase is pretty active. However, the most important things are method of grinding and slow sparging IMHO. and not the enzyme chemistry unless a really unusual sequence was used.. Barry, I repeat, in my opinion this was an excellent contribution = to the HBD readership Thanks. Keep on brewin' Dave Burley Kinnelon, NJ 07405 103164.3202 at compuserve.com Dave_Burley at compuserve.com = Voice e-mail OK = Return to table of contents
Date: Fri, 5 Dec 1997 06:08:34 PST From: "Rosenzweig,Steve" <Steve_Rosenzweig at wb.xerox.com> Subject: Old Homebrew I began brewing in 1989. My extract of choice back then was John Bull Canadian Lager. I didn't lager it at all - just brewed it up with Red Star or maybe even the white pack of yeast that came with it and let it go at room temp. I am generally a pack rat and also a sentimentalist, so I have saved a couple of bottles of a few of those early brews all these years - through grad school and two moves. I've still got 6 or so bottles from then, and the balance of a case of various porters from 95 when I got settled and heavily back into the craft. Last night I had my last bottle of JB Canadian from 1989 - probably a full 8 years old. Not great by any means, but still a decent beer. Light and clear with that same JB taste that got me into homebrewing so long ago. People occasionally ask how long homebrew lasts. The answer is - if you can force yourself to make it last - quite a long time with fairly good results - depending on the brew and how it was cared for. All of my old brews will eventually be gone - need the bottles for this years crop of all grain brews - so as we approach the new year, here's a toast to brews gone by! Steve in Ontario NY (Not even close to Nyack) Return to table of contents
Date: Fri, 5 Dec 1997 22:09:21 EST From: AlannnnT <AlannnnT at aol.com> Subject: beer to distill Since you have to make a 'beer' first before making Scotch I'll assume it's OK to post this to the digest. Any brewers/distillers know how much mash, of what OG, will produce how much double distilled Scotch? Is 5 or 10 % peated malt a good idea? New barrel or used? Of course, this hypothetical discussion is not intended to make anyone distill anything. [Good argument for legalization- If distillation was legal all those Burt Reynold movies would never have been made.] Alan Talman East Northport NY 3 days drive from Jeff- the center of the Homebrew Universe Return to table of contents
Date: Fri, 5 Dec 1997 22:32:52 EST From: AlannnnT <AlannnnT at aol.com> Subject: Stainless fermentors With the help of a skilled welder I am making a SS fermenter. -Currently in design stage. Does anyone have an opinon on lid design, specificaly-large opening versus small. I am leaning toward making a large, 10 inch diameter or so, opening on top. The fermenter will be made from an 18 inch diameter SS duct with a conical bottom. The reason for a large top is to facilitate cleaning. The fermenter will be a "squat" round shape. I expect to gasket the opening and make a clamp setup for the lid. So far I have only seen small openings. I wonder if this is for a good reason that I've missed. Also, to the brewer whose non-beer drinking wife buys him curtains for his new brew room-aka carport, drop everything and run out and buy her something ridiculously expensive and useless for Christmas. Now. Alan Talman East Northport, NY which one is Jeff's house again? Return to table of contents
Date: Fri, 05 Dec 1997 23:27:27 -0500 From: "Capt. Marc Battreall" <batman at reefnet.com> Subject: Grain Mills Hello All, I know this subject has been a thread in the past but I wanted to get some updated and current input from the collective. I am browsing for a malt mill and have narrowed it down to a few. I am looking at both the Valley Mill (tm) and The MaltMill (tm). The price difference is negligable at $30 difference, with the MaltMill being the heavy. However, after viewing both their websites, I am compelled to believe that the MaltMill is a much more rugged piece of machinery and probably the better buy. The Maltmill fixed width roller model is only a few dollars more than the Valley Mill adjustable, but the Valley has a much larger hopper and comes with a adapter for the motorizing. ( I am presuming that they mean a cheap 3/8" drill). Anyway, any testimony from the collective? It is after all, only 19 days to Christmas! (18 days to my birthday!!) so I need to act soon. (Yee Hawww) Marc - -- Hoppy Holidays To All!! Capt. Marc D. Battreall Islamorada, Florida batman at reefnet.com The Fabulous Florida Keys future site of "The BackCountry Brewhouse" Return to table of contents
Date: Sat, 6 Dec 1997 08:40:24 -0600 From: "Michael T. Bell" <mikeb at flash.net> Subject: Conical Fermenters Just noticed the thread on constructing a SS conical fermenter. I have often wondered if it is possible to make one cheapl(a relative term). Could you cut a Sanke keg in half and have a cone welded on to the bottom? Of course, you would need to have the cone manufactured at no small expense, but this method would still be cheaper. Has anyone tried this? Michael T. Bell Boomerdog Brewing Arlington, TX Michael T. Bell Boomerdog Brewing Arlington, TX Return to table of contents
Date: Sat, 06 Dec 1997 08:17:30 -0800 From: Chasman <cwhudak at gemini.adnc.com> Subject: Courage, it's what your right hand is for.... Hello all, A patron at our pub likes my beers well enough but never seems to be completely satisfied. Turns out that he's ruined because he had a beer when he was in Great Britain that he loves and everything else just falls short. It was Director's Bitter brewed by John Courage brewery. Does anyone out there have a recipe for this? I told him that if I could find a recipe that I'd brew him up five gallons at home to shut him up ;o TIA C-- Charles Hudak in San Diego, California (Living large in Ocean Beach!!) cwhudak at adnc.com ICQ# 4253902 "If God had intended for us to drink beer, he would have given us stomachs." - --David Daye Return to table of contents
Date: Sat, 6 Dec 1997 11:04:10 -0500 From: "David R. Burley" <Dave_Burley at compuserve.com> Subject: Larry O'Mahoney,Temp Correction,Alcohol estimation Brewsters: I responded to Larry O'Mahoney in the Big Easy enjoying all those Crescen= t City brews as well as his own and writing about his FWH experiments. I responded, but my message came back. So Larry, please let me know how I can send you my comments. - -------------------------------------- Paul Haaf asks about using a hyrdometer away from its calibration temperature. I use the temperature correction equation < Corr equals 0.0000994 X DelT >where DelT is the temperature difference from the calibration temperature and the actual temperature (Ta - Tc) in Fahrenhe= it degrees at which the reading was taken. Since I normally read within 10 -15F of the calibration temperature, this is fine for most purposes. For= example, a reading of 1.0600 at 70F will be 1.0610 at 60F If you get int= o big temperature differences, there are correction tables in many homebrewing books. I got this number by looking at water density tables = in the CRC handbook page F-5. at 15C water density is 0.999129 and at 20C is 0.998234 so if I assume a straight line and interpolate over this narrow range, I get a correction of 0.000179 per degree C or 0.0000994 per degr= ee F. So for 10F equals DelT the correction is +0.000994 or to within the number of significant figures +0.001. This checks with brewing and winemaking books' correction tables. Alcohol estimation using your hydrometer is pretty easy. Just take DelG equal to (OG - FG) and calculate the approximate value as = %alc v/v equals DelG/F Where in a typical beer F is 7.5. So for OG of 1.060 and FG of 1.20, = DelG is 40 and ~ Alc% is 5.3%. This is only a rough guide and much mor= e accurate methods exist correcting for the fact that F is alcohol dependen= t, among other things. F can vary from around 7.6 at typical low alcohol concentrations for beer to 7.4 at high alcohol contents in barleywine.Man= y books give much more complicated methods and use factors with many significant figures unnecessarily, since these methods are often only goo= d to within 0.5% of the ebulliometric method. It is an estimation, but certainly good enough for our purposes. - ----------------------------------------- Keep on brewin' Dave Burley Kinnelon, NJ 07405 103164.3202 at compuserve.com Dave_Burley at compuserve.com = Voice e-mail OK = </nofill>Windows95 (noun): 32 bit extensions and a graphical shell for a = 16 bit patch to an 8 bit operating system originally coded for a 4 bit microprocessor, written by a 2 bit company, that can't stand 1 bit of competition. Return to table of contents
Date: Sat, 06 Dec 1997 12:44:21 -0600 From: Scott Howard <showard at tandata.com> Subject: Simple way to start siphon I figured out a very easy way to start the siphon when racking without risk of infection and I thought I'd share my discovery. Murine sells a ear wax removal system that contains a small rubber bulb with a tapered end (unused of course) that does the trick. Simply squeeze the air out of the bulb, insert the tapered end into the end of your racking hose, and release the bulb. It does a great job and if you sanitize the bulb before you use it, there's no risk of contaminating your brew. -=-=-=-=-=-=-=-=-=-=- Scott Howard showard at tandata.com Tulsa, OK -=-=-=-=-=-=-=-=-=-=- Return to table of contents
Date: Sat, 06 Dec 1997 18:39:30 -0500 From: Andrew Quinzani <quinzani at mdc.net> Subject: Co2 Pressure (Matt Arnold) >ObBrewing: I'm getting a cornie keg set up going. I've read what I can find in >Papazian and on the 'Net, but no one seems to discuss dispensing pressure. I've >dug through the archives and the topic is alluded to, but not fully discussed. >Basically, I will be drawing a pint or two per day from it. Do I need to leave >the CO2 on a 5-10 lbs pressure (I've got about three feet of hose to the >picnic-style tap)? Or do I just wait until the pressure drops far enough that >it can no longer dispense and then pressurize the keg to about 5-10 lbs? FWIW, >the CO2 canister, keg, and everything else will remain in the fridge. >Later, > Matt Hi Ya Matt, I have been kegging my brew for the last year now and will never go back to bottles! If my friends want to try my beer I tell them "you know where I live!" The pressure depends on a few things....Is the keg going to be in the fridge? Then depending on how much you rolled the keg around to force carbonate it, the 5-10lbs or maybe 12 should be fine, if you are leaving the keg outside the fridge and running the beer through a cold plate then upwards to 30lbs may be needed. You see, the Co2 is absorbed into the beer, how much depends on the temp of the beer. The colder the beer the more Co2 get into it so you need less pressure to keep it where you want it and move it out. I see that you did address the in the fridge question above, I just wanted to explain a bit more and give you a few options. I have a 6 pass cold plate that I have not hooked up yet....can you picture.....6 different beers, all on tap........uuuuummmmmmmm! -=Q=- "Q" Brew Brewery...Home of Hairy Chest Ale - ------------------------------------------------------------ quinzani at mdc.net Return to table of contents
Date: Sun, 7 Dec 97 01:19:31 UT From: "Raymond Estrella" <ray-estrella at classic.msn.com> Subject: Clinitest Sorry but I can not pass this up, yeah it's a weakness...... Dave writes, >The Clinitest method goes back more than a century in >the form of Fehling's and related methods. Its usefulness >in predicting sugar content and its response to various sugars >is about as well known as any chemical reaction can be. >It has been used for reliably detecting sugar content in urine >for many decades. Wow, I checked it out and he's right. The F.G. of my urine shows way to much unfermented sugars. Now, should I re-pitch, or rouse? Ray Estrella Cottage Grove, MN ray-estrella at msn.com ******** Never relax, constantly worry, have a better homebrew. ******** Return to table of contents
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