HOMEBREW Digest #2952 Fri 12 February 1999

[Prev HBD] [Index] [Next HBD] [Back]

		Digest Janitor: janitor@hbd.org
		Many thanks to the Observer & Eccentric Newspapers of 
		Livonia, Michigan for sponsoring the Homebrew Digest.
				URL: http://www.oeonline.com

  denaturing/flaked barley/CaCl2/washing glasses/starters/nutrients/CO2 (BrewInfo)
  Of course hot water freezes faster (Armin Ulrich)
  Historic Porter/brown malt/Weyermann rauchmalt (Jeremy Bergsman)
  Momilies keep rolling in.... (Jack Schmidling)
  "alcohol tolerance" (Jim Liddil)
  The Jethro Gump Report...part 1. ("Rob Moline")
  The Jethro Gump Report...part 2 ("Rob Moline")
  The Jethro Gump Report...part 3 ("Rob Moline")
  Alcohol content and fortification (Rod Prather)
  RE: Rod P.'s "Math challenge" ("S. Wesley")
  re: bottler thingies (Mark Tumarkin)
  Dispensing from kegs without a CO2 bottle / Y2KBW (Ken Schwartz)
  dry hop with Fuggles ? (LEAVITDG)
  Efficiency question: Am I getting enough out of the malt? (LEAVITDG)
  Yeast Autolysis/Yeast Library? (Matthew Comstock)
  Making candi sugar / beer stock (PAUL W HAAF JR)

Beer is our obsession and we're late for therapy! Enter The Mazer Cup! _THE_ mead competition. Details available at http://hbd.org/mazercup Send articles for __publication_only__ to post@hbd.org If your e-mail account is being deleted, please unsubscribe first!! To SUBSCRIBE or UNSUBSCRIBE send an e-mail message with the word "subscribe" or "unsubscribe" to request@hbd.org. **SUBSCRIBE AND UNSUBSCRIBE REQUESTS MUST BE SENT FROM THE E-MAIL ACCOUNT YOU WISH TO HAVE SUBSCRIBED OR UNSUBSCRIBED!!!** IF YOU HAVE SPAM-PROOFED your e-mail address, the autoresponder and the SUBSCRIBE/UNSUBSCRIBE commands will fail! Contact brewery at hbd.org for information regarding the "Cat's Meow" Back issues are available via: HTML from... http://hbd.org Anonymous ftp from... ftp://hbd.org/pub/hbd/digests ftp://ftp.stanford.edu/pub/clubs/homebrew/beer AFS users can find it under... /afs/ir.stanford.edu/ftp/pub/clubs/homebrew/beer COPYRIGHT for the Digest as a collection is currently held by hbd.org (Pat Babcock and Karl Lutzen). Digests in their entirity CANNOT be reprinted/reproduced without this entire header section unless EXPRESS written permission has been obtained from hbd.org. Digests CANNOT be reprinted or reproduced in any format for redistribution unless said redistribution is at absolutely NO COST to the consumer. COPYRIGHT for individual posts within each Digest is held by the author. Articles cannot be extracted from the Digest and reprinted/reproduced without the EXPRESS written permission of the author. The author and HBD must be attributed as author and source in any such reprint/reproduction. (Note: QUOTING of items originally appearing in the Digest in a subsequent Digest is exempt from the above. Home brew clubs NOT associated with organizations having a commercial interest in beer or brewing may republish articles in their newsletters and/or websites provided that the author and HBD are attributed. ASKING first is still a great courtesy...) JANITORS on duty: Pat Babcock and Karl Lutzen (janitor@hbd.org)
---------------------------------------------------------------------- Date: Tue, 9 Feb 1999 18:00:05 -0600 (CST) From: BrewInfo <brewinfo at xnet.com> Subject: denaturing/flaked barley/CaCl2/washing glasses/starters/nutrients/CO2 More old, unanswered topics... Steve writes: >My question is about the initial mix of hot water & grain in >the mash tun. I mash in a converted sanke keg by adding the >strike water, heating it to strike temp, then pouring in the >grain while stirring. I usually hit my mash temp within a >degree , and don't seem to have any real problem with my >brews. >However, a fellow brewer asked me if I might be denaturing >some of the the beta amylase enzymes when the grain first >hits the 164F+ water and maybe don't get as many >fermentables as a result. I do occasionally have a batch >that finishes with a higher than expected gravity, and maybe >this is a contributing factor. Enzyme denaturing is not instantaneous, but I would not be surprised if you found a correlation between the higher FG beers and those mashes that you mashed-in very slowly. Personally, I have not been so blessed as you with hitting mash temps, so what I do is I heat half of my strike water in my mash tun and half in my kettle. I quickly dump all my malt into the mashtun and stir well. I then add water from the kettle until I've hit my target temp. I always make more water than I think I'll need and often I will use it. Stirring the very thick mash I get with this dough-in procedure is tough (esp since I do 1/2bbl batches & have used 46# of malt in a single mash), but it's much easier to get the lumps out of the thick mash than chasing them around a thin mash. *** Darrell writes: >Also, one local pub brewer suggeste puting the flaked barley into the >mashtun when recirculating and sparging...ha anyone heard of this? It depends on how long and at what temperature he recirculates. If it is at 170F and for only 15 or 20 minutes, he/she is getting starchy, wort. Flaked barley is mostly starch (and a lot of beta glucans, by the way) and thus needs to be mashed as long (and maybe even longer) than malted barley. *** Domenick writes: >Put a pinch of the CaCl2 on a plate and if it "melts" then you have >the anhydrous. If it doesn't melt then you've got the dihydrate, >CaCl2.2H20. Not exactly... CaCl2 will keep attracting water in any form, anhydrous, dihydrate, hexahydrate (CaCl2.6H2O)... Anhydrous, given time, will attract water from the atmosphere and make dihydrate, which will then continue to attract water and make hexahydrate... Incidentally, a sealed container of CaCl2 will be mostly one form after a while, but I believe that a pinch on a plate will be a mixture of various forms. CaCl2 is extremely hygroscopic (attracts water) which is why it is used for dessicants! If you buy some, make sure it comes in a sealed package and store it in an airtight container. Take out what you need, right into the scale, if you've got it and seal up the remainder immediately. After weighing/measureing, you can allow it to turn to soup... the ppm of Ca+2 and Cl- this blob will add will not change. >If you have the dihydrate then one gram contributes, >Ca 72.1 and Cl 127.3 Yes, but more specifically, one gram of dihydrate CaCl2 in 1 gallon of water will give you 72.1 ppm of Ca+2 and 127.3 ppm of Cl-. *** Kevin writes: >>>How are you washing your glasses?<< >Hand wash with warm water (Lansing city) and palmolive dish soap, >rinse and let air dry. No, no, no! Never use soap on beer equipment or glassware. I recomend washing soda (sodium carbonate). The second best choice is dishwasher powder (usually mostly sodium carbonate). Avoid dishwasher powders that contain sheeting agents ("no spots!"). Detergent good... soap bad! Soaps will leave a film that kills your head retention. *** Mike writes: >I've been using yeast starters for all grain brewing. I'm getting >conflicting info regarding them. Questions: 1). Am I supposed to decant most >of the liquid in the yeast starter before pitching it into the wort? One >author says to do this and just pitch the very bottom slurry. I've been >pitching the entire yeast starter contents; and 2). What is yeast nutrient >and what is yeast energizer? One brew shop sold me yeast nutrient which was >supposed to be yeast skeletons (?) and yeast energizer which was a white >powder (urea?). However, another brew shop sold me yeast nutrient which was >a white powder (urea?) and yeast energizer which was yeast skeletons. Which >brew shop has it right? Thanks. 1. Ideally, you would like to pitch the yeast when it is just past high kraeusen... while it is still very active. This will give you the shortest lag times and yeast with the highest level of glycogen (this is important for a number of reasons... see the archives for a discussion). If you wait until the yeast has all settled, this optimal time has long past. What I do is allow the yeast in my starter to settle, timing it so that I can pour off the spent wort the day before brewing and then add a small amount of fresh wort. This means that I can make 2 or even 4 liters worth of yeast starter, but then feed the slurry with only 500 ml of wort the day before brewing. This way, I pitch a "large" starter but only add 500ml of "foreign" wort to my batch. 2. Both brew shops might be right. I've found that various manufacturers call their products different things. One companies "energiser" is anothers "nutrient." Bottom line: a simple white powder is most likely diammonium phosphate (DAP). This is best left for vintners. What you want is a mixture of various nutrients, including vitamins and yeast hulls (aka skeletons). This mixture will be tan and will not be all one "shape" or colour (flakes, white crystals, brown powders, etc.). It will also smell mostly like dry yeast. *** Joe writes: >If you do the mass produced route - injected C02 carbonation. You need >to get the beer real cold - (32F). Diffuse Co2 bubbles (as small as >possible). You can have it carbonated in no time at all. Get the >pressure/temp chart and your off. It is not CAMRA compliant, and it >just does not taste as >good (TO ME) refermented in the bottle beers. Sure is real duplicatable and >easier >tho... You need not have it that cold. I have force-carbonated beer at 68F! You simply look at the pressure/temp chart and use that pressure. At 68F it might be 45 psi of CO2. I also don't use a diffuser. I simply shake the keg/PET bottle. I have learned to disconnect the supply hose before shaking so beer doesn't go up towards the regulator, but other than that, it's simple and cheap. Furthermore, CO2 is CO2 and it dosen't matter whether it comes from sugar or from a tank. You might get a miniscule amount of additional unfermentables from DME priming, but the CO2 produced is exactly the same. The taste of force-carbonated beer should *technically* be exactly the same as that from dextrose-primed (and I'm a card-carrying CAMRA member, by the way!). The *mouthfeel* of CO2-dispensed, fizzy, tighly-filtered beer is crap compared to unfiltered, properly-conditioned, gravity- or handpump-dispensed beer, which is nectar. *How* the CO2 got into solution (so long as the beer is still unfiltered and served properly) should not have an effect. Oh... after I force-carbonated that beer at 68F, I cooled it down to serving temperatures and the carbonation was just as expected. Don't try to dispense it at 68F and 45psi!!! Foam city! Al. Al Korzonas, Palos Hills, IL korz at brewinfo.com http://www.brewinfo.com/brewinfo/ Return to table of contents
Date: Tue, 9 Feb 1999 18:07:25 -0700 From: Armin Ulrich <ajulrich at telusplanet.net> Subject: Of course hot water freezes faster The main reason that hot water freezes faster is that the water molecules in the hot water are in a higher energy state (buzzing about faster) and that activity state has a flywheel effect as the water cools down, And that activity facilitates evaporation which cools the water faster that the water which starts out colder. The one caveat is that relative humidity must not reach 100%(which leaves out most home size freezers). Don't believe me try it out, put two containers outside one with hot and the other with cold water in an see which one freezes first. And for a extra low tech answer a few weeks back I saw video from Finland where people threw boiling water into the air where it would freeze before it hits the ground (Temp was -60C). Now why would anyone stand outside in -60 (which is damn cold for those of you which have not experienced it) to boil water when you could use cold water. Return to table of contents
Date: Tue, 09 Feb 1999 18:41:53 -0800 From: Jeremy Bergsman <jeremybb at leland.Stanford.EDU> Subject: Historic Porter/brown malt/Weyermann rauchmalt Looking for advice on the following recipe. I am shooting for an historic porter. I would like to use brown malt, but apparently what's available is non-enzymatic (www.hoptech.com). Therefore I will be using the blend of dark malts I have developed successfully in other porters, but in a lesser amount based mostly on the estimated color contribution of the brown malt. In addition to the brown malt character I want to have a smokey character like older beers might well have had. Peat smoked malt seems wrong for this. Checking the archives finds that while some will make a rauchbier with 95% of this malt, others find this too smokey and I'm not going for Kaiserdom here. 25 and 35% were suggested but one should probably factor in the higher OG of this beer compared to a rauchbier and stick to the lower side so I am thinking around 25%. Here are my thoughts for 8 gallons: 10 lbs Hugh Baird Pale Ale (It's the UK malt I have) 5 lbs Weyermann beechwood smoked malt 3 lbs Hugh Baird brown malt (70L) .5 lbs Caramunich (Dark crystal I have on hand) .4 lbs Chocolate malt 4 oz Black malt 1 oz Roasted barley Predicted OG on my system 1.075. I will hop this to 57 IBUs, with 1.5 oz of EKG and .5 oz Bramling Cross for flavor. Another possible flavor hop I have around is Willamette, but I like the bramling cross. Yeast will be WYeast 1335 (British II?) and a brettanomyces bruxellensis in the secondary, which I will let go several months. In addition to general comments I'd appreciate the following info: -The Weyermann malt is enzymatic, right? Anyone have an approximate deg. lintner? (If it's not bad I could increase the brown malt.) -How about the color of the Weyermann? -Anyone have any other source of brown malt? - -- Jeremy Bergsman jeremybb at leland.stanford.edu http://www.stanford.edu/~jeremybb Return to table of contents
Date: Tue, 09 Feb 1999 21:28:20 -0800 From: Jack Schmidling <arf at mc.net> Subject: Momilies keep rolling in.... From: Alan McKay <amckay at magma.ca> Subject: Is the Schmidling mill as good as a 6 roller? The premise of Alan's question was so absurd that I was not going to dignify it with a response but De Piro's knee jerk answer is at least worth a few words. First of all, NEVER and NOWHERE did I ever claim that any $100 two roller mill was "as good as" a $10,000+ 6 roller mill. From: "George De Piro" <gdepiro at fcc.net> "Alan asks about Jack's claim that his adjustable mill mimics a 6-roller mill: " One final point on adjustable mills is worth putting on the table. It is frequently suggested that the one sided adjustability of the MM is a limitation when in fact, this is actually the key to the so called "text book crush". If you look at the oft published drawing of a six roller mill, you will note that the roller spacings are about .050", .030" and .012" from top to bottom. It just so happens that, when an adjustable MM is set to near contact at the adjustable end, one gets those same numbers at the fixed end, center and adjustable end respectively. The end rusult is that the random distrubution of grain across the length of the rollers provides about the same grist distribution as a six roll mill." "The above is incorrect..... I left my statement in tact because it is not obvious what "is incorrect". The only thing I see even open to discusson is the last sentence, which happens to be about as true as anything Clinton has said in his life. "About the same grist distribution" simply means that when you weigh all the little piles that pass through the sieve test, the weights are close enough not to argue about. That is a fact and has been demonstrated by no less of an authority than George Fix. I do not dispute that by sifting out the husks in a multiroller mill, one gets less husk fracture and this is why I would never claim that it is "as good as" but for our purposes, the grist distribution is/can be about the same. Whether that is of any value to a homebrewer is fodder for another discussion. "A mill with skewed rollers will not mimic this. In this situation, some kernels will be unscathed while others will be obliterated..... This is patently untrue. There is no way a kernel can pass through OUR mill unscathed. There is also no way they can be obliterated if the close spacing is not less than the closest spacing on a multiroller mill. The fixed end is the same spacing as our "pre-adjusted" mill and if grain passed through "unscathed" it would be useless. The other end is user adjusted and has the same attendant risk of maladjustment as a mill with both sides adjustable. It has the advantage that it can not be so maladjusted as to make rubbish because the other end assures a reasonable distribution of coarse "fines" and everything in between across the rollers. I do not know why this is so hard to understand but the proof of the pudding is in the eating and no one has ever contended (until De Piro) that the MM obliterates malt. js - -- Visit our WEB pages: http://user.mc.net/arf ASTROPHOTO OF THE WEEK..... New Every Monday Return to table of contents
Date: Tue, 09 Feb 1999 21:56:08 +0000 From: Jim Liddil <jliddil at azcc.arizona.edu> Subject: "alcohol tolerance" > Date: Sun, 7 Feb 1999 22:44:15 -0500 > From: "Tim Green" <timgreen at ix.netcom.com> > Subject: Re: Maximum Alcohol > > One more note of maximum alcohol levels in fermented beverages, Wyeast > sells a yeast they call Eau de Vie (water of life) #3347. They sell it for > starting stuck fermentations and the production of single-malt beverages. > They claim the alcohol tolerance of the yeast is 21%. > As I have said in the past alcohol tolerance is a porrly defined term. I usggest you check the CRC article I have mention before. Chech the archives. Essentially the research has shown little difference between various yeast strains. Jim Return to table of contents
Date: Tue, 9 Feb 1999 23:45:00 -0600 From: "Rob Moline" <brewer at isunet.net> Subject: The Jethro Gump Report...part 1. The Jethro Gump Report The recent discussion on ethanol levels in beer has prompted me to copy the discussion portion of the Magnus, Casey, Ingledew paper on High Gravity brewing for the HBD.....This is done purely for educational purposes only, and I hope that it stimulates you to seek out the entire paper, and that it satisfies many of the questions that it has for me.... Casey, Magnus, Ingledew..."High Gravity Brewing: Effects of Nutrition on Yeast Composition, Fermentative Ability, and Alcohol Production." "Regular production strains of brewers' yeasts can, with appropriate nutritional supplementation, produce up to 16.2% (vol/vol) ethanol in the batch fermentation of worts up to 31% dissolved solids. This occurs at 14C without incremental feeding, with high yeast crop viability, and within normal brewing time periods (i.e., less than 1 week.) The generalization, then, that strains of saccharomyces used in brewing have only moderate alchol tolerance (9) compaerd with strains used in distilleries (16) does not hold true from a production viewpoint. Ehtanol concentrations of 16% (vol/vol) are considered high, even in the distilling industry. For brewing yeasts to produce these high levels of ethanol witkout an excessively long or stuck fermentation, the wort must contain two types of nutritional supplements; a nitrogen source (provided in this study by yeast extract) and a combination of sterol (provided in this study by ergosterol, the most prevalent sterol in Sachharomyces spp. [34]) with unsaturated fatty acid (provided in this study by the oleic acid fraction of Tween 80). It is important that both supplements be provided simultaneously: the fermentation of high gravity worts then proceeds rapidly under both anaerobic (6) and semianaerobic conditions (fig 1) (Rob here.....fermentation conditions were maintained as anaerobic by continual headspace purging with nitrogen at a rate of 30 ml/min. ......"In special circumstances, however, semi-anaerobic fermentations were carried out where there was no nitrogen flushing, and foam plugs were used in the sampling ports." ) These supplements act by increasing the amount of new yeast cell mass synthesis over the levels seen in unsupplemented fermentations (Table 3.) During wort fermentations, the rate of sugar conversion into ethanol is considerably higher in growing yeast cells (up to 2.0 g'h per g of yeast) than it is in stationery phase yeast cells (as low as 0.06 g/h per g of yeasts) (21, 22) Clearly, it is not realistic to expect the rapid and complete attenuation of high gravity worts by adding only brewing wort syrups to normanl gravity wort bases, as is the current practice, (15). By doing so, lipid and nitrogen deficiencies will limit the rate and final level of ethanol production to levels much below the maximum possible, as discussed below. Lipids that are present in normal gravity worts in growth limiting concentrations (7) must be synthesized by the yeasts in the first few hours of fermentation while oxygen is still present (22). However, the decreasing solubility of oxygen in worts with increasing original gravity (3) results in high gravity worts which, if left unsupplemented, will certainly have oxygen as a growth limiting nutrient. As demonstrated in this report, in worts up to 31% disolved solids, oxygen deficiencies can be overcome by either the addition of 24 ppm ergosterol with 0.24% (vol/vol) Tween 80 as a source of oleic acid or by periods of oqygenation during the fermentation (Figures 4 and 5.) On an industrial scale, the latter would likely be a more economical option. In low gravity worts, (10-12% dissolved solids) a minimum level of 150mg of FAN per liter is required to permit rapid and complete attenuation (24). Virtually all of this nitrogen is utilized within the first 24 hours of fermentation,(31) at which point active yeast growth stops(19). In the unsupplemented high gravity worts used in this study, levels of FAN ranged from 165 - 250 mg/liter. This was not nearly enough to support the necessary degree of of cell growth required to rapidly and completely ferment worts as much as 3 times more concentrated than normal gravity worts. When yeast extract was incorporated into fully supplemented worts, considerably more FAN was utilized by the yeasts than was even available in total in the unsupplemented worts (as much as 320 mg of FAN per liter.) The highest levels of yeast extract required can be drastically reduced by the use of an all malt base.(Fig 5) Jethro Gump Return to table of contents
Date: Tue, 9 Feb 1999 23:50:56 -0600 From: "Rob Moline" <brewer at isunet.net> Subject: The Jethro Gump Report...part 2 The Jethro Gump Report..part 2 Casey, Magnus, Ingledew..."High Gravity Brewing: Effects of Nutrition on Yeast Composition, Fermentative Ability, and Alcohol Production." "It is apparent, therefore, that a frequently mentioned advantage of high gravity brewing, namely, the increased yield of ethanol resulting from the nonproportional increase in cell mass production with the increase in wort gravity (30),is in fact an important disadvantage in worts above the current commercial limit of 16-18% dissolved solids. Although the use of higher levels of non-nitrogenous and cheaper adjuncts is possible in worts up to this limit, above these levels, nutrient deficiencies will prematurely terminate growth and therefore lead to significantly prolonged and in some cases even stuck fermentations. In tthe past, such problems have been attributed to the toxic influence of ethanol, (9, 17) when in fact growth limiting levels of nitrogen and oxygen have not permitted sufficient new yeast cell mass synthesis. Indeed, it appears that Saccharomyces carlsbergenis cna be repeatedly repitched in 30% dissolved solids wort, producing up to 14.2% (vol/vol) ethanol each time, without any increase in in the time required for fermentation or decrease in the extent of attenuation. In unsupplemented worts as low as 15.3% dissolved solids (with 40% adjunct), deteriorations in the rate of attenuation, the end gravity reached, and the final ethanol concentration obtained have been observed, even though the first generation gave normal and complete attenuation.(18) The claim that ethanol concentrations as low as 8 to 9 % (vol/vol) are sufficiently high to kill off a large enough portion of the yeast crop to prevent its use for repitching (35) is therefore not accurate. Supplementation was shown to have no influence on the fermentative tolerance of the yeasts to ethanol(Table 2). this possibility was explored because sake yeasts only produce the 20 to 23% (vol/vol) levels of ethanol if the proteolipid component of Aspergillus orysae is present (17). In other strains of Saccharomyces, exposure to 0.5 to 1.5 M ethanol causes an increase in the proportion of monounsaturated fatty acyl residues in cellular phospholipids (4). Also enhanced are tolerances to the effects of ethanol on generation time, viability, and solute uptake when enrichment with a C18:2 unsaturated fatty acid, rather than a C18:1 unsaturated fatty acid was carried out (35). The early rise and then continued decline in fermentative power values has been attributed to an increase in the cellular levels of hexokinase activity by the buildup of intracellular ethanol levels with time(27). As the ethanol concentration of the Warburg assay increased up to 20% (vol/vol), so did the degree of inhibiton of glycolytic activity. The relationship between the activity remaining (relative to the 0% vol/vol control) and the concentration of ethanol was found to be linear. However, when the IF50 values of these plots were calculated, little difference between the two sets of yeasts was seen at any point throughout the fermentation. The values fluctuated within the range of 10.1 to 13.6% (vol/vol) ethanol, with the highest IF50 values in fact being observed in the yeasts from the unsupplemented fermentations. Improvements in the supplemented fermentations on a per milligram of yeasts (dry weight) basis were not due to supplementation increasing the tolerance of brewers' yeasts fermentative ability to ethanol. The enhanced death of yeasts in the high gravity wort fermentations with increasing temperatures (Fig 3) was not an unexpected result. Ethanol and temperature effects on yeasts are known to be closely related as (i) ethanol becomes increasingly toxic to growth and viability at higher temperatures (25, 26), (ii) ethanol decreases the optimum temperature of fermentation (14), (iii) ethanol decreases the optimal and maximum temperatures for growth (36), and (iv) higher temperatures of fermentation result in decreased final ethanol concentrations in the mash (28). The explanation for the increased inhibitory effects of ethanol at higher temperatures has been attributed to increased accumulation of intracellular ethanol at higher temperatures (26). Therefore, decreased fermentation times arising from higher temperatures of fermentation are at the cost of poor yeast crop viability, which is something that would eliminate their use in brewing. In any case, the increased production of esters and higher alcohals at higher temperatures would preclude the use of temperatures above 14 C for the brewing industry (10). However, in the gasohol or distilling industries, in which end yeast crop viability is not as critical, the combination of nutritional supplemenation and temperatures up to 30C may be more practical. Yeast crop cellular composition (especially glycogen and sterols) were found to differ considerably between anaerobic and semi-anaerobic conditions and to depend on the nutritional supplement used. The level of protein fell consistently within the 40 to 50% range, but the amounts of cellular glycogen and sterol fluctuated greatly. Glycogen levels were all less than 10% in yeasts under semi-anaerobic conditions, regardless of whether they were unsupplemented or supplemented, whereas up to nearly 30% concentrations were seen in the anaerobic fermentations (Table 1). However, the level in the fully supplemented anaerobic yeasts, which gave the fastest feremntation time (6), was 10.5%; this was the only crop under anaerobic conditions to contain less than 26% glycogen. The level of glycogen in brewers' yeasts is an important consideration, as it is the sole source of metabolic energy for lipid synthesis and hexose transport in the first few hours of fermentation (32). Because of this, levels decline during the first 24 hours of fermentation, then rise and peak at levels as high as 40% at the end of the growth phase, before gradually declining during the stationary phase (19, 32). Pitching rates resulting in the presence of 160 to 200 mg of glycogen per liter are suggested to ensure enough glycogen for the synthesis of adequate lipid levels (32). Although this might suggest a potential problem for the repitching of yeasts from the supplemented fermentations, this was not found to be the case, as added lipids can compensate for low glycogen levels Fig 3)." Jethro Gump Return to table of contents
Date: Wed, 10 Feb 1999 00:07:42 -0600 From: "Rob Moline" <brewer at isunet.net> Subject: The Jethro Gump Report...part 3 The Jethro Gump Report...part 3 Casey, Magnus, Ingledew..."High Gravity Brewing: Effects of Nutrition on Yeast Composition, Fermentative Ability, and Alcohol Production." "Like glycogen, sterol levels varied between anaerobic and semianaerobic conditions. Levels in the semi-anaerobically fermented yeasts ranged from 0.85 to 1.09%, depending on the type of supplementation (Table 1), comapared with levels of only 0.27 to 0.56% in the anaerobically grown yeasts. Clearly, oxygen is being introduced during the course of the semi-anaerobic fermentations due to the higher levels of cellular sterols in these yeasts. Brewers' yeasts normally have ca. 0.1% total sterols (dry weight) at pitching but reach 1.0% or greater within the first several hours, utilizing wort oxygen for de novo synthesis (22). The 1.0% level is a maximum ceiling which is subsequently diluted down to a 0.1% lower limit by passage of sterols to daughter cells(22). Based on the results described above, it is clear that cellular sterol levels alone are not the growth limiting factor in yeasts from unsupplemented high gravity wort fermentations. In none of the yeast crops from these fermentations was the lower limit of 0.1% sterols observed. In fact, the lowest level reached was 0.48%, but this level was reached at day 6 of fermentation and remained unchanged up to the end of fermentation (day 12). It was not, therefore, the level of cellular sterols which caused the cessation in new yeast cell mass production in the unsupplemented fermentation, but other growth limiting nutrients. In the yeasts from supplemented fermentations, the addition of the lipids in the supplement elevated even further the levels of sterols away from the growth limiting level of 0.1%. It remains to be determined whether the 16-17% (vol/vol) levels of ethanol reported here represent the true upper limit for brewers' yeasts. As sake yeast can only produce the 20-23% (vol/vol) levels of ethanol by the sequential addition of substrate over a period of weeks (17), it may well be possible with the sequential addition of adjunct to produce beers of up to 20-23% (vol/vol) ethanol. Should this be possible, it would suggest the need for a complete re-evaluation of the definition of alcohol tolerance in the various species of Saccharomyces. In addition, it is shown that the self imposed wort gravity limit of 16-18% for high gravity brewing in industry should not be ascribed to sluggish and stuck fermentations, yeast death, or intolerance to alcohol. It would appear that brewers and alcohol manufacturers could easily consider production of worts with higher graviites and enjoy larger economies of labor, capital, and energy." So, I hope that you have found this useful....I know that I did....I can only apologize if i have mucked up the text from the original.....And while I am not sure of some of the designations, I hope that the gist of the info gets through..... Again, this selected info from the article is reprinted only for educational purposes... Cheers! Jethro Gump Rob Moline brewer at isunet.net Lallemand Web Site Consultant jethro at isunet.net "The More I Know About Yeast, The More I Realize I Need To Know More About Yeast!" Return to table of contents
Date: Wed, 10 Feb 1999 05:41:45 -0500 From: Rod Prather <rodpr at iquest.net> Subject: Alcohol content and fortification I believe the addition of more must is done in Flor sherrys. I am not sure of the process. Once again I have unsupported information, Jeff. What I rememeber what that the Flor was continuously fed while wine was taken off of the vat. The reason was that a flor, or hard yeast cap, only forms in certain situations and is difficult to attain. Once attained, the cap would keep so the vintner wanted to take full advantage of it, thus the feeding process. It is my personal observation that hearty, alcohol tolerant sherry yeasts were borne of this process. Note that sherry yeast frequently have alcohol tolerances in the 17 percent ranges and are noted for their alcohol tolerance. Still you are right, both sherry and port is fortified, usually with brandy. The increased alcohol content halts bottle aging and causes the wine to keep for long periods of time, thus 100 year old ports and sherrys. Secondly, the fortification also has an asthetic value of modifying the flavor slightly for the better. It is my understanding that Sake, on the other hand, can attain alcohol contents in the 20% range simply by yeast accomodation. Poorer quality sakes have also been fortified. These were the ones that were typically drank warm. Japanese and American sake brewers are trying to bring the higer quality, unfortified sake into vogue in the US. These are typically more flavorful, fuller bodied and drank cold. Jeff Renner wrote. > still more clarification. I've just read the entry on Sherry in Alexis > Lichine's _New Encyclopedia of Wines and Spirits_ (1974 ed., OK, not so > new, but neither am I) to confirm my recollection that Sherry is fortified, > and find that it is except for some for domestic consumption. I can't find > anything about the slow addition of more sugars, but that doesn't mean it > isn't done. > Return to table of contents
Date: Wed, 10 Feb 1999 06:37:41 -0500 From: "S. Wesley" <WESLEY at MAINE.MAINE.EDU> Subject: RE: Rod P.'s "Math challenge" Rod Prather asks for a mathematical solution to the following question: If a coil of length L is immersed in a resivoir of temp Tr so that fluid flows into the coil at temp Tin what will be the output temperature Tout. An upper limit on Tout can be found from: Tout </= Tr - (Tr-Tin)e^(-sL) Where s = kp/((rho)AcWv) Here k = thermal conductivity p= the circumfrence of the tube (rho)= density of fluid A =cross sectional area of pipe W= thickness of wall v = velocity of fluid c= specific heat of fluid Note that vA is just the flux of water through the tube (volume rate of flow.) I say this gives an upper limit because the model used to derive this expression depends on the questionable assumption that heat absorbed near the tube is instantly transmitted to the element of water nearby (flow is highly turbulent) and there is also good flow around the outside of the coil. Years of experience putzing around and experimenting with immersion chillers lead me to belive that the circulation created by heating the resivoir will not produce adequate flow around the coil to maximize heat transfer. (Some sort of vigorous stirring mechanism is required.) It is comforting to note that this model agrees with expectations in the limiting cases of L = 0 and L= infinity. For L=0 Tout = Tin and for L= infinity Tout = Tr. Return to table of contents
Date: Wed, 10 Feb 1999 07:15:05 -0500 From: Mark Tumarkin <mark_t at ix.netcom.com> Subject: re: bottler thingies Bill Graham writes: I've spent a fair chunk of change on my brewing setup, but have spent nothing on bottling (except $5 for the old Eveready bottle capper at a garage sale.). I would like to graduate beyond squirting beer into a bottle from a vinyl hose, squeezing it off with thumb and finger when moving to the next. Can anyone recommend a bottle filler? I fill many different sizes, so it would have to account for that. I'm not kegging, so counterpressure doohickies are out. Many people seem to dislike bottling, thinking it is a hassle. I am not one of them. I don't mind bottling at all (although I plan on getting into kegging a bit soon as well). I think part of it is having good equipment. If you have spent "a chunk of change" on your other equipment, you probably won't mind spending a little bit more on the bottling setup - hey, toys are fun!. I use a phil's philler, and am quite happy with it. I would suggest getting a few other items. First, a jet-washer. Second, a bottle tree, and lastly a bench-type capper. I am not familiar with your Eveready - it may be a bench capper. I have found that if you get into the habit of rinsing your bottles right after you pour them (or at least as soon as possible), maintaining good sanitation by blasting the bottles with the jet-washer, putting them into the bottling bucket filled with iodophor, and then draining on the bottling tree is simple. It does seem a little like work, but just think of it as Zen and the Art of Bottle Maintainence. Mark Tumarkin Gainesville, FL way south of Jeff and Al Return to table of contents
Date: Wed, 10 Feb 1999 05:41:47 -0700 From: Ken Schwartz <kenbob at elp.rr.com> Subject: Dispensing from kegs without a CO2 bottle / Y2KBW Running a keg from non-tank CO2 sources has been discussed in length, but if you're looking for an easy solution for dispensing a keg within a few days (like at a party), check out my web page and find the article on "Keg Hand Pump". Easy to rig up and cheap. Since it dispenses ith air, staling of the beer in time is a concern, so plan to consume the whole keg soon (get some help). - ----- Lotsa talk about Millenium BW's. Cap'n Marc wants to make one using Danstar Nottingham. I brewed my "Ninety-Nine Barleywine" in November 1997 (before "Y2K" really entered the vernacular) using that same yeast. I would suggest using at least two packs. This dry yeast can usually be had for $1 or less so it's not like you're straining the yeast budget compared with liquid cultures. Pitch large and oxygenate well. BTW my BW went from 1.092 to 1.017 in about a week. - -- ***** Ken Schwartz El Paso, TX Brewing Web Page: http://home.elp.rr.com/brewbeer E-mail: kenbob at elp.rr.com Return to table of contents
Date: Wed, 10 Feb 1999 07:42:06 -0500 (EST) From: LEAVITDG at SPLAVA.CC.PLATTSBURGH.EDU Subject: dry hop with Fuggles ? Date sent: 10-FEB-1999 07:34:25 I am building up a stock of homebrews for a wedding reception that we are having at our house in June. Knowing that lots of folks like lighter brews I brewed up and Irish Ale (so named primarily because of the yeast, Wyeast # 1084 [4lb Baird's Vienna malt, 8lb Maris Otter 2 row, I cup crystal, 1 oz Hallertau at start, 1/2 oz at 30, 1/2 oz at 15]), mash sched was (partial boil ): 147 F for 40 min, 155 F for 40, OG=1.070, FG=1.014)...Now here is the question: When I tasted it, going into the secondary, it tasted a bit mild (as planned) but I wanted to zip it up a bit, so I dry hopped with 1/2 oz Fuggles...and upon bottling this appears to not have done too much...still pretty mild (malt and hops). Should I have added more, or are these the wrong hops for dry hopping? ...Darrell _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ _/ _/Darrell Leavitt _/ _/INternet: leavitdg at splava.cc.plattsburgh.edu _/ _/AMpr.net: n2ixl at amgate.net.plattsburgh.edu _/ _/AX25 : n2ixl at kd2aj.#nny.ny.usa _/ _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ Return to table of contents
Date: Wed, 10 Feb 1999 08:19:09 -0500 (EST) From: LEAVITDG at SPLAVA.CC.PLATTSBURGH.EDU Subject: Efficiency question: Am I getting enough out of the malt? Date sent: 10-FEB-1999 08:05:56 I have been trying to do all-grain, but withoug a proper sized kettle. Mine is just 20 quarts, so I need to add H2o to get 5 gallons...but I wondered if I could get some feedback from the group as to my procedure... given the equipment limitations...? Here is my typical mash: 3 gal H2o into kettle, take it up to 147 F (or whatever, based upon the malt)...add 10-12 lb malt (sometimes some flaked barley)... this just about fills the pot...heat to temp and let sit for 30- 40 minutes, then heat again up to 155 F (or so) [note: I have tried to draw off several quarts and boil them <deconction?>, then add back at times], and let sit at this second step for 40 minutes... then mash out at 168-170...then I place the grains into a zapap sort of thingy that I have put together, I recirculate until it seems to be running pretty clear...(reheating at times with microwave so as to maintain temp), then I start to draw a pint off at a time, placing it tinto the brewpot, while replacing that pint with a pint of sparge water (trying to watch pH). ..I keep doing this until I can get no more into my wimpy 20 quart kettle.. .sometimes I have a gallon or so to add as the wort boils down. I have generally found that when it starts running clear I find a gravity of about 1.07 , sometimes as high as 1.09... then near the end of the sparging the gravity is usually around 1.02 or 1.03 The OG, once I have chilled and added some H2o is generally around 1.07 , sometimes nearer to 1.05 if I used a few pounds less grain. My question is: Does this seem ok for the equipment that I am using, or should I expect more? I know that there are a lot of variables...so I appreciate any thoughts. ...Darrell <Plattsburgh,NY> _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ _/ _/Darrell Leavitt _/ _/INternet: leavitdg at splava.cc.plattsburgh.edu _/ _/AMpr.net: n2ixl at amgate.net.plattsburgh.edu _/ _/AX25 : n2ixl at kd2aj.#nny.ny.usa _/ _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ Return to table of contents
Date: Wed, 10 Feb 1999 05:24:59 -0800 (PST) From: Matthew Comstock <mccomstock at yahoo.com> Subject: Yeast Autolysis/Yeast Library? Teach a guy how to homebrew, and he will worry himself to death. Jeez. I've been following this thread about yeast autolysis and oxidation with interest(only noticed what I thought was autolysis once in a raspberry mead after about a month in the bottle. It went away after about two months = Lalvin K1V-1116, made a fine mead in the end). Today Fred L. Johnson asked the question that pops up in the archives once and a while - and I've asked recently - "How is storage on the cake of yeast in the primary any different than storage on the cake in the secondary or in the bottle? And if yeast autolysis is such a problem, how can one produce a decent bottle-conditioned beer, such as a barleywine or any other big beer, that is supposed to REQUIRE some aging to produce its characteristic flavors?" I've seen someone, Pat Babcock?, answer this by saying its not the yeast that is a problem in the primary, maybe leading to off-flavors, but the trub and break material. In the past few days, and today, people have commented that autolysis problems are yeast specific. Can we develop a library of this and other information about specific yeast strains. This info could more useful than the manufacturer's comments. For example, I wonder what yeast John Varady is using: "I often leave my beer on the yeast for 3-6 weeks before bottling, skipping a secondary vessel entirely. I find that I get clean, clear beer that carbonates within 2 weeks and has very little bottle sediment. I have never noticed any "meaty" or "rubbery" aromas from this practice and would certainly discontinue it if I did." Maybe we already have a library of 'real' info about yeast strains available. It seems important to categorize our autolysis comments, and other useful comments, by yeast strain, negative or not. Otherwise we will have a stand-off between people like John Varady saying he's never had a problem, and others saying that a week on the primary yeast cake is a sure recipe for disaster, when they may be using very different yeast strains. OK, here's a lame start. I've used Munton's dry ale yeast, Edme dry ale yeast, Wyeast 1056, and Wyeast 1028, and used *only* a primary in all but one case. All batches sat at least 10 to 11 days in the primary, and most for 14 days. I repitched onto the primary yeast cake twice, once using Wyeast 1056 and once with Wyeast 1028. None of these beers had a rubbery or goofy off-taste. Only the beer made with Munton's dry ale yeast tasted different than I expected. It was kind of sweet, estery? - I decided it fermented too warm, about 74 F. The 7.5 EtOH stout I made with Wyeast 1056 was real thick, FG = 1.022, but good. I thought it had a not-unpleasant yeast flavor. Liquid bread, indeed. If there isn't a library already, let decide on a format for this info. Sure we could search the archives for our yeast of interest, but that can be a long exercise. Laters Matt in Cincinnati, OH _________________________________________________________ DO YOU YAHOO!? Get your free at yahoo.com address at http://mail.yahoo.com Return to table of contents
Date: Wed, 10 Feb 1999 08:31:21 -0500 From: PAUL W HAAF JR <haafbrau1 at juno.com> Subject: Making candi sugar / beer stock Can someone send me a recipe for making candi sugar? My attempts at searhing the archives proved my web searching deficiency. TIA. As far as keeping a beer based stock in the fridge longer than a normal stock, isn't most of the alcohol cooked out when you reduced from one gallon to one quart? Paul Haaf ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866] Return to table of contents
[Prev HBD] [Index] [Next HBD] [Back]
HTML-ized on 02/12/99, by HBD2HTML version 1.2 by K.F.L.
webmaster at hbd.org, KFL, 10/9/96