HOMEBREW Digest #3768 Tue 23 October 2001

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  Re: raspberry wheat haze ("RJ")
  LPG van Propane (Ant Hayes)
  Re: Where am I? (gsferg)
  More Rennerian (Jeff Renner)
  Rennerian calculator correction... (Pat Babcock)
  Over-sparging / SWIG ("Drew Avis")
  Re: relationship between sparge temp and sparge time? (Jeff Renner)
  Re: Propane vs LPG ("Mike")
   ("Micah Millspaw")
  Sparging practicalities ("Crouch, Kevin E")
  Re. Iodophor Stains ("Jeffry D Luck")
  Stuck fermentation? (Gary Krone)
  Suppliers (Gary Krone)
  homebrew shops in london ("Robin Griller")
  Re: carbonated cider ("Larry Bristol")
  Re: n/a beer ("Larry Bristol")
  bacterial resistance... ("Alan Meeker")
  RE: Bacteria and Resistance ("Crouch, Kevin E")
  Netscape Rennerian Needs (Brian Levetzow)

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---------------------------------------------------------------------- Date: Mon, 22 Oct 2001 01:02:54 -0400 From: "RJ" <wortsup at metrocast.net> Subject: Re: raspberry wheat haze Steven S <steven at 403forbidden.net> wrote: "what would contribute to haze/muck generated by the fruit (ie:raspberrys)? I kept the carboy at cold (30-40's) temps for a couple of days and the beer cleared quite well. Typical haze for a wheat but it looks less like dirty dish water now. After transfer there was a layer of yeast and what looked like, well i donno, raspberry yuck/protein/sugar/??" Steven, Sounds like fruit pectin to me... If it's not yet bottled/kegged you could try clarifying with Gelatin or Clear-Jel and if your not a purist you could always add food coloring to increase the visual appeal. Return to table of contents
Date: Mon, 22 Oct 2001 09:41:00 +0200 From: Ant Hayes <Ant.Hayes at FifthQuadrant.co.za> Subject: LPG van Propane Yet again this forum is the greatest teacher. I asked my question (Why is propane more dangerous than LPG) for two reasons: 1. I thought that LPG was a mix of propane and butane; and 2. Small canisters of LPG sold by Cadac are very widely available in South Africa -and are probably found in most households. They are not considered particularly dangerous. Perhaps they are safer out here as we don't tend to have basements, and it is generally hotter, so windows and doors are open most of the time. Ant Hayes Johannesburg; South Africa Rennerian coord approx = [13 656; 125] distance in km; true bearing Return to table of contents
Date: Mon, 22 Oct 2001 09:25:07 -0400 From: gsferg at clary.gwi.net Subject: Re: Where am I? Jeff Renner rambled on along these lines: >BTW, perhaps this is a opportunity to catch newcomers up to history >of this bit of silliness. It all began about five years ago after I >made my semi-annual suggestion that people sign their posts with >their name and location. Dan McConnell then poked some good-natured >fun at me when he signed a post with something like "4 miles >south-east* of Jeff Renner, center of the homebrew universe." >Spencer Thomas then continued it with "1 mile SE of Dan, 5 miles SE >of Jeff**, center ..." etc. People picked up on this and were soon >signing with distances, so Jason regularized it. Hah! This explains my confusion to me. Let me explain my confusion to you: I used to be a professional land surveyor- licensed and everything. All told I spent 20 years of my life involved in surveying, the last 8 of them as a self-employed land surveyor. By the end of 1994 I'd had about as much fun as I could stand and it also seemed like a _perfect_ time for my midlife crisis so at the end of the business day on December 31st 1994, I shut the doors of my company and walked away. I ain't looked back since. Anyways, I'm quite familiar with different coordinate systems and map projections- or thought I was- until I started reading about this "Rennerian" coordinate system... I figured I'd just been outa the business too long, that the mapping world had come up with a new means of locating points on the face of the earth in terms appropriate to their intended use (which escaped me at the time), and I left it at that. Now that I know what we're talking about AND I've given my credentials AND I been able to focus my beer-sodden brain on this matter, permit me to render my professional opinion: Rennerian coordinates should be given as [Bearing,Distance] not the other way around- they are after all polar coordinates, and everyone knows polar coordinates are given as direction and distance... right? RIGHT? Anyways, that's my opinion and I'm sticking to it. Now. On the subject of units of measure: There is an oft-cited case familiar to many land surveyors of a boundary description some idiot wrote describing land to be conveyed some place in the south west united states, which description gave distances in terms of "smokes" where a "smoke" was defined as how far one would travel on horseback (presumably at a leisurely pace) during the time it took to smoke a cigarrette (presumably a hand rolled cigarrette). Certainly not the most accurate and reproducible measure of distance, but it would at least get one within a stone's throw (yet another distance measurement unit) or 2 of the destination. Now it seems to me given the usefulness and real utility of these Rennerian coordinates that the distance vector could be given in terms of say "beers" where a beer is defined as the distance one travels on foot (presumably at a leisurely pace) whilst drinking a beer (presumably a homebrew). In keeping with correct polar coordinate designation, they would be given as [Bearing, Beering]. Coming up with a conversion formula for say "miles" to "beers" might be a bit tricky but I'm sure we could agree on something. Thoughts? George- - -- George S. Fergusson <gsferg at clary.gwi.net> Oracle DBA, Programmer, Humorist Whitefield, Maine US [729.7, 79.6] Renerian - -------------- I am a man, I can change, if I have to, I guess. Return to table of contents
Date: Mon, 22 Oct 2001 10:25:06 -0400 From: Jeff Renner <JeffRenner at mediaone.net> Subject: More Rennerian Darrell Leavitt <darrell.leavitt at plattsburgh.edu> signed his post >[9679.9, 27.4] Renerian (if I did the conversion correctly) I don't think so! That would be some 9600 miles from me almost due north, which would take you back down the other side of the globe through Siberia to somewhere (roughly) in the vicinity of Malaysia. Just using Plattsburgh, NY (don't know where your house is) on Steve Jones' calculator gives [545.7, 72.3] Rennerian. Jeff - -- Jeff Renner in Ann Arbor, Michigan USA, JeffRenner at mediaone.net "One never knows, do one?" Fats Waller, American Musician, 1904-1943 Return to table of contents
Date: Mon, 22 Oct 2001 10:34:17 -0400 (EDT) From: Pat Babcock <pbabcock at hbd.org> Subject: Rennerian calculator correction... Greetings, Beerlings! Provide me with the polar vector pair to your lager... Well! In spite of the thesis by our esteemed colleague, George S. Fergusson (and others), I believe the Rennerian Coordinate calculator should display its values in the Henning Coordinate System of [Distance, Bearing] as origuinally defined so as not to confuse anyone associated with reality. Unfortunately, though, to that same definition, we'll be forced to bury Jeff in his back yard in order to make the calculation static. To this end, I propose that we refer to the coordinates in our system as APPARENT Rennerian, pointing to his domicile. I'm sure Jeff would prefer this to his imminent and untimely demise - an event required to mack ACTUAL Rennerian a static number. As for the derivation of the same system in terms of "Beering", I do believe this is worthy of further study! I need a base of reference for the division. If a few intrepid individuals in areas where walking about whilst consuming homebrew is legal (which rules out most Canadian cities - unless you can carry a roof about with you) and each owning a GPS could consume a standard 12oz homebrew whilst walking in a straight line (challenging if you've been in multiple trials of this derivation) could report back with their linear distance travelled and, perhaps, their height, stride length and any impediments to mobility they may be stricken with, we can, perhaps, make this happen in terms of an ideal "average" home brewer... - -- - God bless America! Pat Babcock in SE Michigan pbabcock at hbd.org Home Brew Digest Janitor janitor@hbd.org HBD Web Site http://hbd.org The Home Brew Page http://hbd.org/pbabcock [18, 92.1] Rennerian "The monster's back, isn't it?" - Kim Babcock after I emerged from my yeast lab Saturday Return to table of contents
Date: Mon, 22 Oct 2001 10:33:48 -0400 From: "Drew Avis" <andrew_avis at hotmail.com> Subject: Over-sparging / SWIG Brewers: The debate over when to stop sparging over the past week or so has prompted me to collect some thoughts on a unique brewing method I've been working on that ensures you: 1) will never over-sparge; 2) will brew two different five gal batches in about the time it takes the conventional all-grainer to brew one 10 gal batch; 3) use minimal equipment; 4) can move back indoors (my primary motivator, after freezing my buns brewing through a couple of Canadian winters); and 5) will improve your love life. The technique has been dubbed Split Wort of Increased Gravity (or SWIG) by HBDer Brian Lundeen, and it's really just a combination of batch sparging and concentrated wort boiling. The technique is fairly simple, but involves a couple of calculations which I won't outline here, because I'm still working on them! Basically, you need a large mash tun and two large (20 qt) stock pots. You mash enough grain for a high gravity 10 gal batch (20-24 lbs). Batch sparge, collect 17-18 qt in the first stock pot, and put it on the stove to boil. Add some roast malts and/or crystal malts to the tun, add the second batch sparge water, recirculate, and collect a second round of sweet wort. Even at the end of the sparge I've found the SG to be around 1.020, which means poor efficiency, but who cares? It only costs an extra buck or two in grain, and you avoid all the perils of over-sparging. Boil the second pot. Of course, boiling 18 qt of wort in a 20 qt pot takes some practice and constant vigilance, but it can be done without boil-overs. Keeping track of two boiling pots & hop schedules that are 20 min apart is also challenging, but I try to keep a list of what needs to be added when, prepared well ahead of time. Hop, chill, aerate & rack to fermentors. Top up to five gals with R/O water, and pitch the yeast. Recipe formulation is tricky, as you're dealing with concentrated worts which mean reduced hop bitterness extraction, and hitting a specific gravity is complicated by the fact that you're collecting the first 9 gallons of runoff when a conventional sparge would be 12-13 gallons. I find I can brew a stronger pale beer and a lighter dark beer (such as an IPA and a mild, or helles bock and a brown ale), which is great because 10 gals of the same beer (even fermented w/ 2 different yeasts) gets to be a bit tedious. Anyone else out there brewing like this? Drew Avis in Merrickville, Ont. Return to table of contents
Date: Mon, 22 Oct 2001 10:41:20 -0400 From: Jeff Renner <JeffRenner at mediaone.net> Subject: Re: relationship between sparge temp and sparge time? darrell.leavitt at plattsburgh.edu asked from somewhere in SE Asia: >There must be a positive correlation between the maintenance of sparging >temperature, and the total aparge time...? I suggest this in that I am >now in the process of sparging an Alt...and have found that my time has >decreased by nearly 1/2 hour (from 1.75 hours) and I think that it is >due to the fact that my sparge temmp has stayed above 160F. >Is this the case for others? The viscosity should go down, but that is still a long lauter. I generally collect about 9 gallons in ~45 minutes. I could do it much faster if I opened up the tap. There is a discussion on UK-HB right now (I imagine Tony Barnsdale will reply) on speed-lautering. Tony completes his runoff in ten minutes! What keeps you from running off your wort faster than 75 minutes? A well established filter bed ought to allow very fast runoff. BTW, a note for everyone. Many people seem to use the term sparge to refer to the runoff. It isn't - it's from Latin "spargere," to sprinkle, and refers to the water you add. The German term "lauter" or runoff is more appropriate. In other words, you shouldn't have trouble with a stuck sparge since it's only water! Maybe a stuck mash or stuck runoff. From O.E.D.: 2. Brewing. A spray of warm water sprinkled over the malt. * 1839 Ure Dict. Arts 107 The malt is exhausted by eight or ten successive sprinklings of liquor.., which are termed in the vernacular tongue, sparges. * 1869 W. Molyneux Burton-on-Trent 244 The `sparge' is set to run on the malt an additional quantity of water. Pedantically Jeff - -- Jeff Renner in Ann Arbor, Michigan USA, JeffRenner at mediaone.net "One never knows, do one?" Fats Waller, American Musician, 1904-1943 Return to table of contents
Date: Mon, 22 Oct 2001 11:23:30 -0400 From: "Mike" <brewski at inet99.net> Subject: Re: Propane vs LPG Working in a refinery that makes propane, among many other products, I ask one of the chemists about this. LPG is liquid petroleum gas not liquid propane gas. Propane, butane and others are LPG. Propane is more damgerous then some and less dangerous than other LPGs. It depends on which LPG it is being compaired to. I too thought that LPG and propane was one and the same thing. Mike Return to table of contents
Date: Mon, 22 Oct 2001 11:03:20 -0500 From: "Micah Millspaw" <MMillspa at silganmfg.com> Subject: >Date: Sat, 20 Oct 2001 10:38:39 -0400 (EDT) >From: leavitdg at plattsburgh.edu >Subject: bacteria...resistence? >We hear that virus can develop a resistence to antibiotics, correct? >Why is it, then, that bacteria cannot develop a resistence to, say, >for example, chlorine? >Are they not intelligent enough as creatures to do this? >Please excuse the naivete...my field is psychology..not biology... >Happy Brewing! > .Darrell The bacteria that often infect breweries do become resistent to to various sanitizers and biocides. To combat this it is common to rotate the type of sanitzer used every month or so or to ' shock' with a dissimilar sanitizer. I do not know specifically of any brewery bateria that are resistant to clorine ( a strong oxidizer ), but the use of clorine is very rough on the equipment. At my home brewery I use (for sanitzing) iodaphor 90% of the time and the other 10% I will use perycetic acid. It keeps the nasties on their toes (if they had toes) Micah Millspaw - brewer at large Return to table of contents
Date: Mon, 22 Oct 2001 16:49:45 -0000 From: "Crouch, Kevin E" <Crouch.Kevin at emeryworld.com> Subject: Sparging practicalities Hi everyone, since I basically started this controversy, I should probably be there when the trub hits the fan eh? We've heard from many spargers with many different techniques, all of which will work quite well to determine where you are at gravity-wise in the sparge process. I think a good summation of the fears, problems, and solutions that we have heard is that some people want or need more control than others and the various tools that we own are representative of that. There are two BASIC issues to consider when figuring when to stop sparging, and I am going to simplify it to the anticipated shagrin of those who feel that a grasp of the nuances of organic chemistry are essential to good brewing practice. 1)As many have said, the best of your mash will already have been extracted at gravities way above 1.010, and depending on your water and the grist composition, sparging down even this far might be adding pollutants at the expense of a few extra points of gravity. A good rule to remember (when talking about leaching polyphenols from grain husk) is that on a scale of Highest risk to lowest risk, high pH (>8) water with a pale grist is on the MAXIMUM risk end while dark grist with more neutral water ~7 pH is on the LOW risk end. If this concerns you, or if you suspect this might be the source of off flavors in your beer, then you must KNOW YOUR WATER, read more about these effects, and alter your sparge procedure accordingly. If it doesn't concern you, then don't worry about it, your beer will taste just fine. For example, when I lived in Bellinghame WA, the water from the local PUD was softer than holy water and I never had to worry about this until I moved to Vancouver, WA which has a significant temporary hardness to the water. Now I take great care to remove the CO3 from my water, or monitor my PH and sparge gravities to keep from polluting my beer. 2)Sparging efficiency can change dramatically from one brew to the next due to variables such as grist composition, water chemistry, mash technique and schedule, or even the active enzyme content of that particular batch of barley malt. If you don't monitor your mash efficiency, you risk greatly diluting your gyle. This means, of course that you will either have to accept that you are brewing a dunkel bock rather than a doppel bock, or that you will be boiling forever. Which do you favor, volume or gravity? For example, I just brewed a pumpkin ale on Saturday using 50% Munich in the grist. My mash efficiency was Loooowww. I had hoped to achieve 1060 with 20 lbs of grain, but I didn't account for the low enzyme content of the grist and realized that after extracting only 5 gallons out of 12, my gravity was already coming out at 1.033 (using a hydrometer and Pro Mash to estimate). I was able to correct for this and salvage a decent amount of extract, but had I not monitored the gravity, it could have been a disaster. I ended up with 8 gallons of wort at 1053 after 90 minutes of boil. Being that it is a pumpkin ale, the gravity isn't such a big deal, so it was easy to swallow. Other styles, however, are not so forgiving. Have we beat this to a pulpy mess? I supect so. Kevin in the 'couve Kevin Crouch Vancouver, WA coord (accross the river from Portland, OR) Return to table of contents
Date: Mon, 22 Oct 2001 11:25:43 -0600 From: "Jeffry D Luck" <Jeffry.D.Luck at aexp.com> Subject: Re. Iodophor Stains > Drew Davis asks about removing iodophor stains. > > Rick Theiner suggested sodium metabisulfie but doesn't know > where to find it. I don' t know if it works for idophor stains but you can find it at your homebrew supply store. Check the winemaking section. ...And to add to Darrells paranioa: Homebrewer: a yeast's way to make more yeast. Jeff Luck Salt Lake City, UT Having a wonderful wine. Wish you were beer. Return to table of contents
Date: Mon, 22 Oct 2001 12:52:28 -0500 From: Gary Krone <gkrone at execpc.com> Subject: Stuck fermentation? I brewed a batch of Robust Porter last week and activity in the airlock started like crazy the next day. After that it stopped cold. I just checked the SG and it is at 1.020. OG was 1.046 at 80 degrees. Should I pitch another batch of yeast into it to get the SG down closer to the recommended FG of 1.012? Or should I just rack into into the secondary and let it go? Thanks, Gary Krone 7617 50th Ave Kenosha, WI 53142 gkrone at execpc.com (262) 697-5041 Return to table of contents
Date: Mon, 22 Oct 2001 13:12:55 -0500 From: Gary Krone <gkrone at execpc.com> Subject: Suppliers Does anyone know of any Home brew supply stores in S.E. Wisconsin, preferably in Kenosha? Thanks, Gary Krone 7617 50th Ave Kenosha, WI 53142 gkrone at execpc.com (262) 697-5041 Return to table of contents
Date: Mon, 22 Oct 2001 14:48:25 -0400 From: "Robin Griller" <robin_g at ica.net> Subject: homebrew shops in london Re the question on homebrew shops in london, there is the 'shop' attached to the Pitfield brewery near old street station. Not particularly good as a homebrewing shop (hops stored in baskets in the middle of the shop iirc!), but has a very very good selection of bottle-conditioned beer and does carry homebrew supplies and is relatively easy to get to, being within walking distance of the tube station. Robin Return to table of contents
Date: Mon, 22 Oct 2001 15:17:39 -0500 From: "Larry Bristol" <Larry at DoubleLuck.com> Subject: Re: carbonated cider "Milone, Gilbert" <gilbert.milone at uconn.edu> queried about carbonated cider: I have experimented with several batches of sparkling cider over the last few years. There really is no trick to it at all. Simply put your apple juice into a fermenter, pitch a nice yeast starter, ferment, then bottle (or keg) like you would any beer. If bottling, use an appropriate amount of priming sugar. I keg and place it under CO2 pressure for force carbonation, just like most of my malt beverages. OK, the truth is there ARE a few special considerations. Ideally, you should use very fresh juice extracted from very fresh fruit. But you also can make a nice cider from apple juice you buy at the grocery store (read the label carefully). Either way, I would recommend using pure, unsweetened juice. Also make sure the juice contains no preservatives, as this will have a tendency to suppress your yeast. The yeast you choose is very significant to the final result, perhaps more so than it is with beer! You need one that will contribute very little flavor of its own. It is difficult to keep the cider from going completely dry, even with a yeast with low attenuation. If you want it dry, then you do not have to do anything at all. Otherwise, you might consider means of stopping the fermentation once a target gravity is reached. Left to its own devices, the cider will typically have a FG of 1.000 (or even lower)! You may want to add some yeast nutrients, as apple juice does not contain everything needed to make ordinary ale/lager yeast happy. I have also been pleased with the result of adding a small amount of malic acid to the wort (must?). This yields a slight pear flavor. Finally, you might consider adding a small amount of cinnamon after fermentation. This is easier to do when kegging. Simply toss a few whole cinnamon sticks into the keg. This gives it a flavor like apple pie, but I advise caution about using too much! I have never attempted to add cinnamon to cider going into bottles. I suppose it could be done with ground cinnamon, but you will have to be careful to get it distributed evenly; it does not dissolve in water. Maybe cinnamon could be boiled in the water used for priming sugar. Is all this too vague? The best thing to do is experiment until you find the flavor profile that you like the best. Start with this complicated recipe and work from there: Sparkling Cider (5 gallons) 5 gallons pure, unsweetened apple juice yeast OG - 1046 FG - 1000 No boiling, no hops, no nothing. After fermentation, bottle (or keg) as usual. Relax and enjoy! Larry Bristol http://www.doubleluck.com Bellville, TX (coordinates unknown!) Return to table of contents
Date: Mon, 22 Oct 2001 15:29:51 -0500 From: "Larry Bristol" <Larry at DoubleLuck.com> Subject: Re: n/a beer Lonzo McLaughlin <lonkelm at yahoo.com> queries about non-alcoholic beer: This is going to seem wierd, but my understanding is that it is ILLEGAL for a homebrewer to attempt this! It is legal for individuals to make beer, wine, and other naturally fermented beverages for their own personal consumption. Most of us also know that it is illegal to distill the alcohol from such beverages. The fine point of the law is that you must be licensed if you want to extract alcohol from naturally fermented beverages. It does not matter what you intent to do with that alcohol, even if it is your intent to discard it. It is illegal to do so without a license. At least, this is my understanding. My advise is to make beer with a very low alcohol content. I recently managed to get a reasonably passable beer with only 2.2% ABV. It had an OG of 1030 and FG of 1013. (It was an accident - I certainly was not trying to do this! <grin>) Larry Bristol http://www.doubleluck.com Bellville, TX Return to table of contents
Date: Mon, 22 Oct 2001 16:06:38 -0400 From: "Alan Meeker" <ameeker at mail.jhmi.edu> Subject: bacterial resistance... Darrell posted: - ---------------------------------------------------------------------------- We hear that virus can develop a resistance to antibiotics, correct? Why is it, then, that bacteria cannot develop a resistance to, say, for example, chlorine? Are they not intelligent enough as creatures to do this? Please excuse the naivete...my field is psychology..not biology... - ---------------------------------------------------------------------------- The answer to your first question is no, viruses don't really develop resistance to antibiotics. Partly this is a semantic issue as "antibiotics" aren't used to treat viral infections. Other drugs, commonly referred to as antivirals are used against viruses, and viruses can indeed develop immunity to them (drug-resistant strains of HIV spring to mind). Typical viruses are little more than DNA packaged in a simple protein coat, and are totally dependent upon our cells for their replication. It is debatable whether they can truly be considered a form of life themselves. Essentially, they are sub-cellular parasites. Bacteria, on the other hand, are much more complex than viruses and are free-living entities, containing much of the complex machinery that makes up a living cell. They are much more like us than is any virus. Fortunately, their cellular machinery is different than that of ours, and it is precisely these differences that we exploit, and target, with antibiotics. The goal is to use an agent that knocks out part of the bacterial machinery but that leaves our own cells' machinery untouched. Bacteria can, and do, develop resistance to antibiotics, often times as a result of over-prescription or improper use of the particular antibiotic in question. This is fast becoming a big worry in the medical community, especially now given big run on Cipro due to the anthrax scare. How do bacteria become resistant? In a nutshell, here's what happens. When you develop a bacterial infection you are under siege by a population composed of literally millions and millions of individual bacterial cells. Within this population there exists random variations caused primarily by mutations. Some of these variants (a rather small proportion of the population, actually) will, by chance, be more resistant to any particular antibiotic (interestingly this is true of the population even /before/ it has ever been exposed to the drug in question). Now, let's say you go to the doctor and he gives you a prescription for tetracycline. You fill it and the instructions say to take the drug for the next 3 weeks. However, after the first week or so, the antibiotic has killed off the majority of the bacterial population, lessening your symptoms to the point that you feel you're better and you decide, therefore, you no longer need to take the antibiotic. The bacteria are not completely gone however, and the bacterial population that is left, though much smaller than it was, is now enriched for the tetracycline-resistant cells. If the bacteria now continue to grow and are able to overwhelm your immune system, the infection will re-appear, but there's a good chance that now it will be resistant to tetracycline due to the fact that the antibiotic-resistant cells, initially a minority in the population, are now well-represented. Now, why can't bacteria develop resistance to an agent like chlorine? Well, it's mostly due to the fact that an agent like chlorine is a much more generalized toxin than an antibiotic. Remember, the antibiotic is targeting a specific component of the bacterial molecular machinery. Something like chlorine on the other hand is a much more general toxin, one that doesn't do precise targeting, and is actually toxic to all life forms, not simply bacteria. Another good example of such an agent is heat. You can develop some limited resistance, up to a point, but above a certain temperature heat will destroy anything we define as living simply because of the physics involved. To take an extreme, hitting bacteria with a blowtorch will certainly kill it and there's no way it's ever going to develop resistance. This is why heat is so useful for sterilizing things. Hope this helps -Alan Meeker Lazy Eight Brewery "Where the possibilities are limitless" Baltimore, MD Return to table of contents
Date: Mon, 22 Oct 2001 21:49:34 -0000 From: "Crouch, Kevin E" <Crouch.Kevin at emeryworld.com> Subject: RE: Bacteria and Resistance >We hear that virus can develop a resistence to antibiotics, correct? >Why is it, then, that bacteria cannot develop a resistence to, say, >for example, chlorine? >Are they not intelligent enough as creatures to do this? >Please excuse the naivete...my field is psychology..not biology... .Darrell, this is a great question! I think the answer lies in the graphical depiction of what happens when bacteria are given a bath in a chlorine solution. Did you ever see U571? First, the cell wall of the bacterium is bombarded by chlorine molecules which deteriorate the structural proteins and transport enzymes by oxidizing certain amino acids. Within seconds the barrier between it and the world it lives in begins to rupture, water molecules start flooding into the cell uncontrollably and, like our doomed U-boat, it explodes. Being the amazingly crafty demons that they are, however, it is not out of the question that they COULD develop a resistance to chlorine. They have found ways to thrive in radioactive deposits, deep sea vents at ungodly temperatures, and can utilize petroleum products as a nutrient sources. The problem is that chlorine acts on so many different kinds of molecules and would require massive rearranging of structural and biochemical features to overcome. It is also interesting to note that many kinds of gram+ bacteria ,which are generally not harmful to humans, are not affected by chlorine. Lactobacillus and Pediococcus are both gram+ bacteria and I'm not sure how they are affected by chlorine. Also, giardia is resistant to chlorine and must be filtered or boiled out. Antibiotics, on the other hand are specific to the type of microbe you are trying to supress. They often disrupt only one biochemical pathway, or one structural feature of the cell (disrupting certain cell wall components for example). It only takes one or two crafty mutations for a bacterium to overcome this weakness and keep our pharmaceutical companies afloat! Kevin Crouch Vancouver, WA Return to table of contents
Date: Mon, 22 Oct 2001 21:57:35 -0400 From: Brian Levetzow <levetzowbt at home.com> Subject: Netscape Rennerian Needs I exchanged an e-mail with Steve (author of the Rennerian calculator that beat me to the punch!) about the minor issue that his calculator and the Netscape browser seem to be having. In the name of service (not competition, since we're using the same basic calculations, and I clearly lost in the photo finish), those having problems using that calculator via Netscape can visit mine. I've hosted it at: http://members.home.net/levetzowbt/homebrew/rennerian.html It's the only thing I got in my homebrew directory right now.... Mmmmm, bottled up a Belgian tripel last week, 8.3% and yummy, even green! Can't wait until the holidays! And I bottled my APA last night, which officially ran me out of bottles! Guess I need to get a-drinkin'.... Prost! - -- +++++++++++++++ Brian Levetzow ~ Laurel, MD Rennerian coords [425.7, 118.5] Return to table of contents
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