HOMEBREW Digest #2996 Mon 05 April 1999

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	FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
		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


Contents:
  Refractometers ("George De Piro")
  Aluminum pots ("Bill Tobler")
  Re: Sugar Substitute (Beer and Diabetics) (Jeff Renner)
  Murphy's stout (Jeff Renner)
  Diacetyls: myths, missconceptions, and dog dirt. ("Dr. Pivo")
  Wrong method, Sulfite/aldehydes (Dave Burley)
  Braggot, Mead, & Sparkaloid (Ted McIrvine)
  1 Barrel RIMS ("Richard Hooper")
  Temperature Control ("Sandy Macmillan")
  Diabetes+Beer+correction ("Stephen Alexander")
  Canadian Bud (Alan McKay)
  Diacetyls II: (do you think my wife knows?) ("Dr. Pivo")
  Looking for kegs in NC ("Mike Beatty")
  Broken thermometer in Brew Pot! ("Jeffrey S. Fabrizio")
  Water Softeners/Fructose/M&BS on Diacetyl (AJ)
  2-tier website with pics ("C and K")
  OG, yeast questions ("Conan Barnes")

Beer is our obsession and we're late for therapy! Enter the Buzz-Off homebrew competition! Entries due by 6/19/99. Competition 6/26. 2000 MCAB qualifying event! For more details, see the HBD Competition Calendar for June 1999 (http://hbd.org) 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: Sat, 03 Apr 99 00:07:32 PST From: "George De Piro" <gdepiro at fcc.net> Subject: Refractometers Hi all, I'm stumped. I've got a catalogue that lists several types of refractometers. Some of them are significantly more expensive than others because they claim to have "ATC" (Automatic Temperature Compensation). I can't imagine why you would need that with a refractometer. How long could it take a few drops of liquid to equilibrate to the temperature of the instrument? What am I missing? Have fun! George de Piro (Nyack, NY) Malted Barley Appreciation Society http://members.aol.com/MaltyDog/maltind.html Return to table of contents
Date: Sat, 03 Apr 1999 07:00:12 +0000 From: "Bill Tobler" <WCTobler at brazoria.net> Subject: Aluminum pots Another case of not listening to the little voice in your head. Porcelain verses SS boiling pots, no contest if you think about it. I knew I was throwing $35 away when I bought the Porcelain pot, but noooo, I don't listen to the little guy yelling "don't buy it!! Don't buy it!!" 5 boils later, I've got a chip in the bottom, and the spot welds for the handles are exposed. I already have a good 9 gal. aluminum pot, perfect size for 5 gal. batches. I do boil crawfish 2 or 3 times a year, but I don't think that should be a problem. I sure would like to hear from some people using aluminum, and maybe some who used to, but don't anymore. Private e-mails fine. I plan on getting a good SS pot, but need to get a few more 5gal batches under my belt, then decide on wether I want to go to 10 gal or not. Is a spigot in the boiling pot worth the trouble/expense in a five gal system? Does it need to be high enough to keep the hot/cold break and hops out? I would think a screen would plug up. Thanks for the help. To Better Brewing Bill Tobler Lake Jackson, Tx. Return to table of contents
Date: Sat, 3 Apr 1999 09:41:57 -0500 From: Jeff Renner <nerenner at umich.edu> Subject: Re: Sugar Substitute (Beer and Diabetics) Ian_Forbes at AICI.COM (Ian Forbes) wrote: > All beer have carbohydrates. Yeast can't >convert them all. You can get an idea of how much carbohydrate >is present in a beer by looking at the calories. A "lite" beer >may have around 100 calories. One gram of carb has >approximately 4g carb, so a "lite" beer has 25g of carb. You forgot the caloric value of the alcohol at 7 calories/g (and a small amount of protein at 4 cal/g). If a 340 ml. bottle of lite beer has 3% ABW, then this equals ~10 g. alcohol for 70 calories, leaving only 30 calories attributible to carbohydrates (and protein). Jeff -=-=-=-=- Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu "One never knows, do one?" Fats Waller, American Musician, 1904-1943. Return to table of contents
Date: Sat, 3 Apr 1999 09:42:07 -0500 From: Jeff Renner <nerenner at umich.edu> Subject: Murphy's stout Dave Burley <Dave_Burley at compuserve.com> writes: >Murphy's Irish Stout is a sweet Irish Stout as compared to >Guiness which is a Dry Irish Stout. While Murphy's is definitely softer than Guinness (two n's, Dave!), as is Beamish, I wouldn't categorize it as a sweet stout. Nor does Michael Jackson, who puts all three in the dry stout category in his _Beer Companion_. He says of Murphy's, "Less assertive than Guinness, but drier than Beamish, [it] has a suggestion of well done toast, a light roastiness, and a firm but relatively light, smooth body." You could check just how sweet it is with Clinit ... . No, I won't go there. Since Guinness is the overwhelmingly best known of Irish stouts, it is easy to think that it defines the style (dry stout). The other two are nice variations, and there are many other fine examples produced away from the Emerald Isle. They shouldn't have to be Guinness clones to be good examples of the style. Jeff -=-=-=-=- Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu "One never knows, do one?" Fats Waller, American Musician, 1904-1943. Return to table of contents
Date: Sat, 03 Apr 1999 17:06:44 +0200 From: "Dr. Pivo" <irv at wireworks.se> Subject: Diacetyls: myths, missconceptions, and dog dirt. There has been much discussion of late about diacetyls. Nearly everything said about there formation has been correct in some situation, and totally incorrect in others. They are some tricky buggers. Pilsner Urquell has been mentioned as containing them, but what has not been mentioned is that they are the cornerstone of ALL Czech and Slovak pilsners. I have never tasted a single beer there without quite perceptable levels of them with the exception of one. It was a non filtered thing, and both the brewmaster and myself were in agreement that the yeast remaining in the bottle had "had them for lunch". If you like numbers on these things, one generally considers the perception threshold for pentadione to be about 0.1 mg/litre. Pilsner Urquell is (was) at about 0.6-0.7. Few other breweries in Czecho actually know where there levels lie, as the measurent is a costly thing that requires alcohol extraction first. My mass spectrometer of a tongue and nose says the other Czech beers lie between abou 0.4- 0.8, the Slovals can range higher Yes it is true that they can be formed without either yeast or oxygen playing a part at their actual point of formation. On the other hand, who cares? Oxygen (and particularly WHEN it is introduced), and the state of the yeast will have such profound effects on the formation of diacetyl, that the theoretical fact that they can be formed independently is "meaningless". Why would I have invested so much energy into trying to understand diacetyl formation? Because I just love them, when in balance. This is not a particularly popular view among brewers today, and why should it be thus? It seems that in the 1950's someone "discovered" that two deadly brewery problems, namely yeast mutation (le petite mutants), and some forms of infection (particularly the dreaded pediococcus) pitched diacetyls. The thinking then was that if one simply brewed in a manner to remove all diacetyls, one then would not cloak these problems when they started to rear their ugly heads. Very clever indeed. To me it is a bit like finding out that the pH of a lemon goes down when it spoils, so inventing a pH neutral lemon, so that one would know right away when it was starting to go off (it would sour). This would also be a very clever way to quality control check lemons. It wouldn't be much of a lemon, however. I do find it a bit amazing that this all more wide spread industrial "trick", has also spawned a whole generation of homebrewers who think that diacetyls are "bad". They are not. They simply "are", and you may or may not want them. I want them. They are very difficult things to control, however. First let me clear one missconception. The taste has been described as "buttery" by some. It is by no means a smell or taste that reminds me of butter in any way. Furthermore it is certainly not the taste which is accepted as describing a "buttery" tone in wine tasting (A good Chardonnay can have a buttery tone). It is "Butterscotch" and not "butter" (does anybody really think these things taste the same?.... if so I'm not having a sandwich at your house.) If you want to find another taste that it leans toward it is "honey"... and not just any honey (those are complex things, too). Try getting a tin of Australian "leatherwood" flower produced honey. That has a distictly diacetylic tone. I mentioned that they are tricky buggers to manage and I find they are. I think a perfect balance of malt tones, body, diacetyls, and some base bittering with aromatics on top are a heavenly combination. There are two big problems with them however. 1) They are deathly hard to predict. If I predict I am going to get a certain level, hop accordingly, and they don't turn up, I end up with a grossly over-hopped beer. If on the other hand I tone down my hopping and they arrive in force, I get what I call an "unopposed" diacetyl taste. I have recently tasted two American examples of this. One was brewed in Colorado at a small brewery(wish I could remember the name) and the other was "Red Hook" from Washington. I don't care much for that style, but some folks do. 2) The other great problem is that they don't keep well. An "old barrel" beer with diacteyls is not terribly pleasant. Here we can begin talking about butter, as it has a bit of "rotten butter" taste. I've never known if it is oxidation of the diacetyls themselves, or the combination of diacetyls with other oxidation products that causes this particular unpleasantness. I wouldn't rule out the latter, as they are incredibly complex "taste compliments" (see hopping comments above). Examples of spoiled diactyls would be if you take an exported Urquell (please, take it). Other good examples are found all around the Baltic States. A Lithuanion or Estonian beer are really quite lovely... but they don't last long. It might be worth a pilgrimage there to taste some "before" and "afters". They are, as I said, really quite nice when fresh, and if you are really lucky, you might get an example of unchanged technology, when you pop the cap off a half liter bottle and find the inside lined with cork! Now, how many remember the last time you saw one of those? I do. It was back when the commonly held perception of "good sanitation practices", was when you passed a bottle of beer around, you first wiped the tip of it on your tee-shirt in a back and forth screwing motion, to make sure you didn't get the other guys "germs" before you took a swig. Never mind that you had just been wrestling on the grass in that same tee-shirt, and rolling around where the dog empties its bladder, among other things. Oh well, we are all nothing other than humans, very prone to developing ritualistic behaviours, and once we've burned them into our brains, very difficult to be shaken from our beliefs. Here seems quite a nice place for perpetuating them. Dr. Pivo Return to table of contents
Date: Sat, 3 Apr 1999 10:18:33 -0500 From: Dave Burley <Dave_Burley at compuserve.com> Subject: Wrong method, Sulfite/aldehydes Brewsters: I basically agree with Brian Rezac that we should not stifle brewers by making some brewing techniques/recipes off limits - if the brew is good. Adding coconut to a stout recipe is one thing, promoting bad practice by example on a national scale is another. Steeping unmalted grains in a recipe is not just "inefficient" as Brian claims - it is bad practice, as others have pointed out. It may be possible to "get away" with it in a dark stout since the clarity is not an important issue here. But the concern expressed by HBDers is that others will think this is an OK method for all beers and produce cloudy, unstable beers without perhaps knowing why and become discouraged and quit brewing early in their career or at best drink less than desirable beers. Better to use this as an instructive point in time and show the prospectrive extract brewers that it is necessary to gelatinize all starchy adjuncts by boiling and then use a malt extract which still has the ability to produce sugars from the starch ( contains Diastase). Use iodine to check the endpoint. This will go a long way towards helping brewers understand a basic principle of brewing ( starch conversion) and give them a lesson in sound practices. This way you do not have to change the recipe ( which somehow has a political life of its own), just the procedure. - --------------------------------------------------- Uncle AJ suggests the use of a refermentation as a method of diacetyl removal. And suggests also that metabisulfite additions may be used to chemically reduce the ketones. It is not necessary to reduce these ketones and aldehydes as they will likely form a sulfite complex which has low vapor pressure. ( Remember your qual Organic Chemistry?) However, at the pH of beer, only a small fraction of the metabisulfite will exist as the sulfite at any one time. Generally sulfite in beer is not a good idea in contrast to wine because of beer's higher pH. Refermentation in which fermenting beer ( and some additional amino acids, esp valine from the added wort) is by far the best method, since the new yeast will actually consume these by-products from the earlier fermentation. - ------------------------------------------- Keep on Brewin' Dave Burley Return to table of contents
Date: Sun, 04 Apr 1999 00:41:12 -0800 From: Ted McIrvine <McIrvine at ix.netcom.com> Subject: Braggot, Mead, & Sparkaloid I suspect that I'm the only meadmaker in my homebrew circle. About 5-6 of the Grumpy Old Brewers of Staten Island are excellent brewers and give terrific advice about recipes and brewing, but alas, Braggot, Mead, and Sparkaloid aren't part of their brewing experience. (The guy who organizes our competitions even goes so far as to maintain that Cider and Mead should NOT be part of the Best of Show, which means we don't have to compete with Frank Salt, who was cider-maker of the year last year.) I've done two braggots. One was basically a very strong Scotch ale in which the honey got lost in the roast and sweetness. The second was basically a Belgian Trippel (about 12 pounds of DWC Belgian Pils malt with 5 lbs of honey added just before strike) and I'm pleased with the balance of honey and beer tastes. I've been using sparkaloid as a clarifier. It seems to clear the haze beautifully, but I never seem to get rid of the sparkaloid residue, which settles to the bottom as a fluffly white powder. I used about a tablespoon, cooked it to a paste, and let it sit in the braggot for about 6 days before bottling. Alas, I have clearer brew, but more stuff sitting at the bottom of bottles. Any suggestions? Cheers Ted - -- McIrvine at Ix.Netcom.Com College of Staten Island/CUNY http://www.csi.cuny.edu/academia/programs/mus.html http://www.csi.cuny.edu/arts/calendar.html Return to table of contents
Date: Sun, 4 Apr 1999 09:28:50 +0200 From: "Richard Hooper" <richard at dundee.lia.net> Subject: 1 Barrel RIMS Dan Kasen wrote [on HBD of 1st April] :- >Having made a RIMS system for a ten gallon system, I would like to know >if it is practical to do a one barrel RIMS? Yes, it is indeed practical. I have been brewing successfully on a 200 litre RIMS [just over a barrell & a half] for over two years now. My system uses 1 inch diameter piping and a series 5 Little Giant pump. I crush my malt to about 1.7mm, get a fair amount of powder and sometimes a set mash. A good stir usually sorts that out. Saccharification typically takes an hour and a half [South African malt] at 65 degrees but I do a half hour rest at 70 degrees as well. I find I need a protein rest as well, or I get a cloudy beer. I can supply more details if any-one is interested [private e-mail]. Regards Richard Hooper Dundee, South Africa Return to table of contents
Date: Sun, 4 Apr 1999 10:34:30 +0300 From: "Sandy Macmillan" <scotsman at ncc.moc.kw> Subject: Temperature Control Dear All Has anyone any experience with the cooling and heating systems running on 12 volt and using the Peltier effect, Seems to me that these could be the bases of relatively cheap and quiet temperature control. They appear in picnic coolers and they seem to be getting more powerful. Post or private e-mail. If I get enough I will post a view. Sandy Brewing in a dry place Return to table of contents
Date: Sun, 4 Apr 1999 08:58:31 -0400 From: "Stephen Alexander" <steve-alexander at worldnet.att.net> Subject: Diabetes+Beer+correction Ian Forbes correctly states many of the issues involved in diabetes and enjoying alcohol, however I would like to expand on what he has said and make one very important correction to his post. What's it about ? - Non-diabetics maintain blood glucose level(BGL) at 100mg/dL which is a good thing since critical organs including the brain use only glucose for energy. Other organs use fatty acids(FA). Some organs can switch between the two. Your blood only contains a 5 minute supply of glucose energy tho' so it's necessary to carefully control the glucose in and out of the bloodstream. The BGL glucose comes from several sources; carbo foods are broken down, converted if necessary to glucose; humans store several hours worth of energy as the carbohydrate glycogen in the liver; glucogenic pathways can convert proteins and fats(the big energy store) into glucose. The glucogenic mechanisms are painfully slow as any dieter knows. If your BGL is too low, the pancreas releases a signaling protein, glucagon, which tells the liver to start using glycogen as a glucose source and also starts up the glucogenic pathways. Also those organs that can use FAs as an energy source switch to reduce the glucose drain. This is what happens a few hours after your last carbo meal. If you BGL gets high from carbo foods, your pancreas signals with the protein insulin, your liver stops producing glucose from glycogen, and does the reverse. The dual source organs switch to glucose, but most important, insulin tells all the cells that it's time to utilize glucose. In diabetics, either the insulin is absent, deficient, or the cells can't detect the insulin well. In all of these cases BGL stays high and the cells starve in the midst of plenty. Treatments either enhance insulin production or replace insulin with injectable human insulin produced by genetically altered E.coli (and you thought E.coli were the bad guys). Ian and my wife dispense their insulin via a pocket sized computer controlled pumps which simply matters but do not provide a feedback mechanism. - -- Glucose is among the most effective carbohydrates at increasing BGL, but all sugars, and starches can effectively do this. Sugar isn't the cause of diabetes, nor is it some sort of diabetic 'poison'. It's just another carb that must be carefully accounted for in the diet since it, like a plate of pasta, will directly result in blood glucose. Different carbs do increase the BGL at different rates, but the relationship between the carb complexity and the rise in BGL isn't simple. Tables of the speed at which various foods increase BGL, called "glycemic index", have been compiled (see http://www.nutramed.com/diabetes/glycemicindex.htm for an example). There are many surprises - mashed potatoes are almost as effective as honey or glucose, but apples and bananas are much less effective. - -- *** IMPORTANT CORRECTION **** The only significant error in Ians note, and it is a serious one for diabetics follows: >One gram of carb has >approximately 4g carb, so a "lite" beer has 25g of carb. ... >I can immediately send the >proper amount of insulin into my body (for the above example it >would be about 4 units). Ian undoubtedly meant to state that there are 4 calories (4.2kCal/gm) per gram of carbohydrate. This is a good rule of thumb which applies well to sugars and starches *BUT* *NOT* to alcohol. Ethanol is technically a carbohydrate and has considerable calories (5.7kCal/gm) but doesn't really follow the rule and cannot be accounted for in this way. Taking this much insulin in response to alcohol calories seems likely to result in hypoglycemia. One 12 fl.oz 4.5% alc beer contains approximately 88 calories from alcohol - so the 100 calorie lite beer might well contain only 8 calories (2 gm) of normal carbohydrates. 4cal(1gm) of protein and the remainder from alcohol ! Ethanol is different than the other carbs in that it is not converted to glucose, so it doesn't directly impact BGL as do pretzels and pasta and residual dextrins. In fact alcohol consumption can halt other mechanisms that keep BGL high. To quote 'Biochemistry', 2nd ed, Mathews and van Holde, Benjamin & Cumming Pub.Co, 1995, pp561: "Although it is possible to visualize pathways by which ethanol could be converted to glucose, ethanol is actually a poor gluconeogenic precursor. In fact ethanol strongly inhibits gluconeogenesis and can bring about hypoglycemia[low BGL], a potentially dangerous decrease in blood glucose levels." The text goes on to cite the reactions and describe why the ethanol is converted to lactate and released into the blood where it is taken up and used in muscle tissue and esp the heart in the form of lactate - and not converted to glucose. I am not a physician - but my best guess is that taking sufficient insulin to cover all the alcohol calories could easily result in hypoglycemia. It is probable that the ethanol, once converted to lactate, will reduce the total glucose demand of your system somewhat - but this may well be a slow process. And the conversion of ethanol to lactate requires considerable energy up-front. Also I would be concerned about starting to drink with even slightly low BGL and so relying on the "fasting" glucogenic mechanisms, with which the alcohol will certainly interfere, for BGL stability. The magazine, "Diabetes Forecast", March 1999, pp64, suggests treating the alcohol calories as fat calories for the purpose of calculating insulin requirements. For example using the ADA "Exchange" system, a 90 calorie lite beer (almost all from alc) is 2 fat exchanges, while a 150 cal regular beer (90cal from alc, 60cal from carbs) is 1 carbo exchange + 2 fat exchanges. The article also has specific suggestions about eating some carbs before drinking and being extremely careful about hypoglycemia for 8-12 hours afterward due to alcohol interference with glucogenesis. Of course you should consult your physician - and to repeat - I am not one. Steve Return to table of contents
Date: Sun, 04 Apr 1999 10:10:08 -0400 From: Alan McKay <amckay at ottawa.com> Subject: Canadian Bud I've never tasted or smelled anything like that in CDN Bud. Labatt's also brews Guinness under license, but if you compare the Labbatt Guinness with the real Guinness you can buy either in cans or at a pub, they bear very little in common. My guess would be that CDN Bud is completely different from US Bud. cheers, -Alan - -- "Brewers make wort, yeast makes beer" - Dave Miller's Homebrewing Guide http://www.magma.ca/~bodnsatz/brew/tips/ Return to table of contents
Date: Sun, 04 Apr 1999 16:50:01 +0200 From: "Dr. Pivo" <irv at wireworks.se> Subject: Diacetyls II: (do you think my wife knows?) I have recently exposed my lascivious attitude to the flavour and aroma of diacetyls. It is something that has been going on for quite some time. It was on one of my first "fact finding" (<- read: liver pounding) trips to England in the '70's, I bumped into Sam Smith's Ale. I didn't know why I liked that beer so much, nor when I went to Czechoslovakia the first time, what it was that drew that complex odour so brilliantly into my nose (like hugging an armfull of roses). Though I was already brewing at the time, there wasn't "much" literature out there, and it was quite a while before I found out that these things were "diacetyls" and that one somehow had to get a handle on them. I've been spending a lot of time since then trying to do just that. Now to digress into further anecdotes: 1) I was sailing off the coast of New South Wales, when we popped out a carton of cheap Lambrusco in the evening.... it was full of diacetyl. Back on land I immediately looked up the same brand, only to be dissapointed... they weren't there. I then coupled the situation of the heat and the rocking motion in the hull, and bought another one. This one I threw behind the driver's seat on the tray (flatbed) and let it drive around the sheep paddocks in the middle of the Goulburn Valley sommer (hot as hades) for a week. When I cracked that one....Voila! they were back. 2) Quite often in the summer, when I have a long distance between my brew house and cellar, I'll put empty kegs on the porch for some days before taking them back to the brew house to clean them. Sometimes I can crack an empty that had no perceptable diacetyls during consumption, that formidably explodes with them after the yeast residues and a tiny bit of beer sits in the sun a few days. 3) I once tasted a wine at a tiny winery, where one of the whites had a subtle diacetyl tone. I asked the winemaker what he had done differently with this one. He replied that he had used a "carbonic maceration" - crushing the grapes in a CO2 atmosphere instead of open to the air. Now why would I bring up these silly tales? Because in the first two instances, heat has caused the formation of diactyls, and in the last one, depravation of O2 may have encouraged their development..... exactly the opposite of what we are taught in both cases. I might even mention, that at least one brewery uses a slow temperature REDUCTION, in order to reduce diacetyl levels. I guess that's why I blow half a pint of homebrew through my nose, and collapse in cramps of mirth each time I read the advice given: "You had better give it a diacetyl rest, if you want to remain true to style". This is of course referring to the German technique of raising the temperature up over a day in order to degrade diacetyls. I think you can see, that in some conditions that will actually PRODUCE diacetyls.... I'd be pretty sure I had them in the first place, and that that technique elliminated them with my yeast and brewing conditions, before I accepted that oft repeated poor advice. As to getting rid of them (as someone with a keg full of them asked)? The easiest thing in the world. They are extremely volatile (which is why they give off so much odour), and your scrubbing idea is exactly right. Krauzening is mentioned as a means of control. Krauzening can create them. Krauzening can destroy them... it depends on how you do it. I mentioned in my last post that "unopposed" diacetyl, is even more dissapointing for me than not getting them at all. When I have created something, and the diacetyls arrive in strength, and I have grossly underhopped for their presance, I have tried dry hopping and artificially carbonating in the keg in order to at least boost the hop flavour.... they always dissapear completely. If you want to remove diacetyls you might make what I call an "in line hop filter" http://www.magma.ca/~bodnsatz/brew/columns/jirvine/salvage.html I gaurantee they won't get through that thing. I have also noticed I can lose them by "non intentionally" scrubbing... like repeatedly venting overpressure for easy tapping and then recharging before the next use. I've even seen them go on holidays over a single night, when I've not remembered to recharge a partially filled keg, and let it "flatten out" over night (I just can't imagine what state I was in when I allowed THAT to happen). So how does one assure their creation, and keep them at a managable level? I don't know. Or more properly, I sort of know how to do it, but have no worthwhile "rules" to pass on, as there are so many things that effect it, that what works for me, might well do the opposite for you. This is getting pretty long. I once posted mine and others experience with intentionally creating them on RCB. I'll try and dig that up and post separately. Dr. Pivo Return to table of contents
Date: Sun, 04 Apr 1999 13:46:52 -0500 From: "Mike Beatty" <mikebeatty at mindspring.com> Subject: Looking for kegs in NC Hello all- I am preparing to move into kegging...anybody in the NC area looking to get rid of a couple? I'll trade you some bottles... ;-) Thanks! Mike Return to table of contents
Date: Sun, 04 Apr 1999 15:41:48 -0500 From: "Jeffrey S. Fabrizio" <jethro at i1.net> Subject: Broken thermometer in Brew Pot! Hello! I have a question about glass thermometers and their contents. I will first give you some background so you will know why. Today, I did my first all-grain brew, a Russian Imperial Stout. After a nearly perfect experience mashing and lautering (thank God!), I put on the kettle to boil and put the thermometer into the kettle to check the temp. It is one of the glass floating types. Unfortunately, when I went to remove the thermometer, I noticed that it had broken. I used about fifteen pounds of grain, and five ounces of hops, and I really didn't want to chuck the whole batch, so I continued on, thinking that I only had a packet of yeast to waste at that point, and that I would try to research any impact after I had finished. The part of the thermometer that broke was the very bottom. No mercury escaped. I repeat: *NO MERCURY ESCAPED!* The thermometer cylinder with the mercury inside itself was undamaged. Only the glass tube that it is in broke. So, I figured that the only thing in my brew was a little glass, a bit of that red wax(?), and some tiny lead(?) balls. Not much of the wax came out, and only about half of the balls. I then tried to use my newly constructed counterflow chiller which failed dismally, but that is another thread. 8^) To compensate for the glass/wax/balls, I ran the wort through a funnel filter into a bucket, and then ran that into another bucket through a nylon hops bag, then through the funnel filter again. I saw lots of balls in the bottom of the brewpot, but didn't search for the glass pieces. I am *sure* that any particles of glass that might have somehow made it into the fermenter are smaller than could possibly do any harm. My questions are these: 1.) Are those balls made out of lead, and if so, are they going to harm my brew (or me?) after having been boiled for an hour? 2.) Is that red "wax" actually just wax? Can it harm anything? 3.) Am I correct to assume that my glass philosophy was correct, and anything left (which can't be much) couldn't hurt? 4.) Has anyone else had this happen to them, because I feel really dumb! This was a really important batch to me, and I really would hate to throw it away. But I will not hesitate to chuck it if it could mean harm to my wife or me. Any information would be really appreciated. Thank you for reading. Jeff - -- Finding new ways to screw up after only four batches! Return to table of contents
Date: Mon, 05 Apr 1999 00:37:08 +0000 From: AJ <ajdel at mindspring.com> Subject: Water Softeners/Fructose/M&BS on Diacetyl In #2993 Joe Rolfe had a couple of comments about salt based water softeners. I'd like to point out that the vast majority of these are cation exchangers only thus anions, in particular chloride, sulfate and bicarbonate levels are not effected. As the resin is backwashed with brine (sodium chloride) during regeneration, there may be a small increase in chloride content just after regeneration but this should drop off rapidly as residual salt is washed away during normal use. Also, there is little point in getting full before and after analyses done. Just check the hardness coming out. It should be a couple of ppm as CaCO3 at most. Given this calcium and magnesium will have been replaced milliequivalent for milliequivalent by sodium. Also, iron is quite easily removed to a sufficiently low level for brewing without any special treatment equipment. Simply oxidize any "clear water" (Fe++) iron (aerate vigorously) to Fe+++ and filter through sand or some other relatively tight filter medium which should take on an ugly brown stain. The stain is Fe2(OH)3, the same stain that is the reason why most people treat for iron in the first place. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * RE Ian Forbes' comments on sugars in #2995: Sucrose (table sugar) is a dissacharide comprised of 1 each glucose and fructose units. Maltose is a dissacharide comprised of 2 glucose units. Thus, fructose is a simple sugar compared to maltose and sucrose. The initial metabolism of fructose is by a different pathway than glucose so that,as I recall (admitedly somewhat hazily), insulin has less of an effect on fructose metabolism than glucose to the extent that diabetics have less trouble with it than with glucose and carbohydrates which contain it (sucrose, maltose, dextrins, starches...). * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Dave Burley is skeptical about metal ions serving as oxidizing agents for aceto lactic acis. M&BS does indeed say "Molecular oxygen is not necessary for this oxidation and other electron donors ( Cu++, Al++ and Fe+++) also increase the formation of diacetyl from a-aceto lactate" This is obviously a misprint. Substitute "acceptors" for "donors" and it makes sense i.e. Fe+++ grabs electrons from acetolactate oxidizing it and at the same time being reduced to Fe++. I see no reason to discount M&BS's statement because of this simple error which I have made many times myself (i.e. get confused over which way the electrons go in redox). Dave requests a balanced equation. I offer the following: OH CH3 | | CH3-C-COOH + 2 Fe+++ <--> C=O + 2H+ + 2Fe++ + CO2 | | C=O C=O | | CH3 CH3 Is it correct? Who knows, but it is balanced and doesn't seem too absurd given that we know that diacetyl comes from oxidative decarboxylation of acetolactate. M&BS says that the exact oxidaton mechanism is not known but that enzymes are not required but the overall reaction would have to look something like what I've given. Dave also comments that the metal ions are in low concentration in beer. In fact iron and copper are found in amounts up to 0.8 mg/L in some beers. As diacetyl is an oxidative problem we can assume that the wort has an oxidized ORP and that, therefore, these ions tend to be in the oxidized states ready to grab electrons from wherever they can get them. These ions are not, of course, the only electron grabbers in an oxidized wort nor can we probably assume that reducing their presence (most come from malt husks) would aleviate diacetyl problems. * * * * * * * * * * * * * * * * * * * * * * * * * * * Also on diacetyl: I did set out to test the idea that metabite might reduce it but before I got even one measurement done my "assistant" (wife) broke the special adapter the assay requires so there will be no experiments until I can get that replaced. I had to drink all that Pilsner Urquel I had bought to do these experiments with. - -- A. J. deLange Numquam in dubio, saepe in errore. Return to table of contents
Date: Sun, 4 Apr 1999 19:22:40 -0700 From: "C and K" <Cuckold at cornerpub.com> Subject: 2-tier website with pics I have built a 2-tier, and not much experience at it yet. However, learned much on the way. So much was learned from other nice homebrewers on the net, that I put up my own site. There were quite a few lurkers, and many comments requesting pictures. I now have completely revamped the site, with thumbnails, and many digital pictures, describing nearly everything. Hope someone finds it useful. http://www.geocities.com/Paris/Salon/3768/Brewery.html Thanks, Scott and Elke Seldom correct...but never without doubt Return to table of contents
Date: Sun, 4 Apr 1999 11:19:13 -0400 From: "Conan Barnes" <barneco at earthlink.net> Subject: OG, yeast questions howdy folx, planning to try my hand at a partial mash this weekend, but i need to find a few quick answers first. I've read that for a partial mash, you do the mash, then add extract to get the SG up to target. til now, i've been strictly a kit brewer, and the directions that are included tell me to take a gravity reading after the boil, before adding the yeast. this is where my confusion comes in. i'm planning to do a full boil and my recipe calls for an OG of 1.054. is this the reading before i boil?(HBD discussions on all-grain lead me to believe this is the case). or is this the OG after the boil, as the kit instructions would have me believe? I hope I'm not making a false assumption by thinking that an hour boil will change the SG. Hrm, now that i think about it, what amount of water should i start with if I'm trying to brew a 5 gal batch? Heh, so i guess what i need to know is, how much water should i start with and what SG should this amount be before the boil if I'm using a recipe that calls for an OG of 1.054 for a 5 gal batch? wow, didn't realize i was so confused :P. second question, for this batch i'm going to try and step up my yeast starter to 1/2 gal or so before i pitch it. i'm wondering what the correct procedure is for transferring the yeast when i make the step(s). do I 1)pour off the old wort(beer) and add fresh wort to the yeast cake in the old starter, swirl, and then pitch to the next starter, or 2) just swirl to get the cake off the bottom and pitch the whole shebang, old wort and all, to the new starter, or 3) something that i haven't thought of? Thanks much in advance, Conan Barnes Columbus, GA Return to table of contents
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