HOMEBREW Digest #1501 Mon 15 August 1994

Digest #1500 Digest #1502

		Rob Gardner, Digest Janitor

  Re: Dry Hopping/Keg Fermenting (Dion Hollenbeck)
  Re: Waste Water, Hop poles (msadul)
  Re: Phils Philler(TM) (Joel Birkeland)
  How do Chicagoland brewers treat their water? (Jay Weissler)
  More on Forfeiture laws ("Glenace L. Melton")
  Hydrometer temperature correction ("William F. Cook")
  hardness and boiling/chantrelles/Richard's beginner's guide (Algis R Korzonas +1 708 979 8583)
  raking/Britain's "best" beer/beer engine (Algis R Korzonas +1 708 979 8583)
  thermal air currents/gushers/Anchor Porter yeast guess (Algis R Korzonas +1 708 979 8583)
  hot water kills plants (Sean Rooney)
  Re: That fresh beer flavor/Closed systems/CHEAP Cornelius kegs ("Mark B. Alston")
  Using Pure Oxygen to Aerate Wort (MJones)
  specific gravity stuff (DGERTH)
  Corrosion of 304 Stainless Steel ("Palmer.John")

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---------------------------------------------------------------------- Date: Fri, 12 Aug 94 10:01:19 PDT From: hollen at megatek.com (Dion Hollenbeck) Subject: Re: Dry Hopping/Keg Fermenting >>>>> "Randy" == Randy M Davis <rmdavis at mocan.mobil.com> writes: >> Stephen Lovett asked about a fermentation lock on corni kegs that >> won't require modifying the keg. Randy> I have not tried this because I brew 5 gal. Imp. batches and Randy> the keg is too small for fermentation, but why not remove one Randy> quick connect stem and push a piece of plastic hose over the Randy> threaded stem. An airlock stem should provide a good seal when Randy> inserted far enough into the other end. If the hose is just Randy> long enough to accomadate both of the rigid parts, the airlock Randy> should be well supported and not fall over. I ferment in kegs so I know for sure. Here is a little treatise I have written on keg fermentation. Since I have had about 6 people ask me for it in the last week, it is probably worth posting to the HBD. dion Dion Hollenbeck (619)675-4000x2814 Email: hollen at megatek.com Staff Software Engineer Megatek Corporation, San Diego, California - -------------------------------------------------------------------------- Some notes on fermenting in soda kegs ===================================== Both primary and secondary fermentation can be done in soda kegs. When both primary and secondary fermentations are done in kegs, racking is less prone to infection than other methods of fermentation because it is done through a sanitized hose into a sanitized keg and all of it done in a closed system pushed over by CO2. This means that you never have to start another siphon again. A non-obvious trick is to use liquid dip tubes (these are the tubes attached to the liquid "out" valves - the ones the beer actually flows through when leaving the keg) which are shorter than standard length so that when you rack, the trub is left behind. The length to cut off will vary depending on how deep a sediment layer you usually get. I use 1.75" shorter than normal for the tube in a primary fermenter and .75" shorter for the tube used in a secondary fermenter. I use a blowoff tube on the primary fermenter which goes down into a bucket with about 3" of sanitizer solution. It is attached to the gas in valve body which has been modified by removing the inside poppet valve. The poppet valve is the little round thing in the center of the valve body. When you remove the valve body from the keg and look inside, yoy see a triangle with a rivet through it and a spring. This is the bottom of the poppet. To remove the poppet from the valve body, remove the valve body from the keg, place it threaded end down on the floor and use a pin punch to push gently down on the poppet. It will drop down and out.Just get some vinyl hose to fit snugly over the valve body. If you cannot get a tight fit, use a hose clamp, but I have never needed one. The size tubing I use is 5/8", but your size may vary due to the diameter of the valve body (I have pinlock kegs). When sanitizing for racking from primary to secondary, you not only need to sanitize your secondary keg, but the transfer hose as well. This can be done by filling the keg completely with sanitizer solution and then sealing the lid. Attach your transfer hose to the liquid out and open the free end QD (Quick Disconnect - the fitting your beer or gas hose attaches to) fitting (I have made a special adapter for this). Attach a source of hot water to the gas input and force sanitizer solution through the transfer hose until it is completely full and then close the free end. Stop transferring and let it all sit full of sanitizer. When rinsing, be sure to use the same technique with rinse water to rinse out both the liquid side of the keg and the transfer hose. You might ask, why not just soak the transfer hose in sanitizer? Well, you could, but using the hose to let the solution run out of the dip tube and valve body sanitizes those parts, which if you just fill the keg with sanitizer will not be touched because they will be filled with air and prevent sanitizer from entering. Replace the poppetless primary gas valve with a valve body with a valve in it and pressure the primary to 10psi. Purge the secondary with CO2 and seal it up and pressurize to 10psi. Weigh the primary on a scale and take it off. Put the secondary on the scale and leave it there so you will know when the transfer is almost complete. Attach a bleeder valve to the gas valve of the secondary. Bleeder valves are commercially available and are basically a QD fitting with a brass Tee in which are a pressure guage and needle valve. They allow one to measure the *real* pressure in a keg (the guage on the CO2 regulator only registers how much CO2 will be applied, not the actual pressure at the destination). Attach the CO2 from your tank to the primary and boost the pressure to 15psi. Spray off both liquid valve bodies with bleach and then with water. Attach the transfer hose to the primary first and then to the secondary. Beer will begin to flow immediately. Crack open the bleeder valve on the secondary until the pressure drops down to about 7psi, back off the regulator pressure on the primary to about 10psi. Allow the transfer to continue until the secondary weighs about 5 lbs. less than the primary weighed. Put your hand on the liquid QD on the primary and release the lock (on pinlock, turn the ring, on ball lock, lift the collar) while keeping your hand firmly pushing down on the QD to keep it fully engaged. This will allow you to release the QD immediately when the hose begins to suck air. Watch the hose closely and as soon as it sucks air, disconnect from the primary. Reach over and close the bleeder valve on the secondary. While you will usually suck a tiny amount of trub up just as it sucks air, if you leave the transfer hose on after that, the rush of air past the bottom of the dip tube will suck trub in in ever increasing quantities. Racking from secondary to conditioning keg is identical except that you will have a regular length dip tube in the final keg. Return to table of contents
Date: Fri, 12 Aug 1994 08:16:29 -0400 From: msadul at interactiv.com Subject: Re: Waste Water, Hop poles npyle at hp7013.ecae.StorTek.COM writes > All this talk about hot water (from your chiller) killing the grass, bushes, > etc., has me very skeptical. I've seen people trying to use hot water to > kill weeds but I've never seen much success, even when they do it repeatedly. Enter data point #1. When I was brewing a batch (10 gal.) early in spring, there was still about a foot of snow on the ground. The drainage area I usually use for washing my brewing equipment (using the hot water from my immersion chiller) was iced over, so I decided on a gravely patch next to the grass. Unknown to me at the time, the ground under the gravel was frozen. All of my chilling water flowed through the gravel, over the ice, under the snow and onto the grass. Later in the spring I noticed a large, 1 sq yard, puddle shaped area of dead grass in that area. Now it's the middle of August and the dead grass has been replaced by a puddle shaped area of dirt. As far as I'm concerned, hot water is an effective sanitizing agent for your grass and soil. ;-) Continuing on with the thread on hop poles: evanms at lcac1.loras.edu (Mark Evans) writes: > I use a method I read in a hop article. I cut down a few weedy, > sucker trees that grow in a nearby wood. (these are not significant > varieties, locust, whatever) I make sure they are about 20 feet tall and > fairly straight. I sink 1-2 6' metal fence posts in the ground and then > secure the trunks to the fence post with sturdy romex wire (leave the white Likewise, but my poles are 20-30 feet. > insulation on) Twist tight. I run three baling strings up to the top and > let the hops creep on up. They've gone way past the top this year, but it > hasn't hurt their growth. When I get early crops--like this year--I > un-twist the wire, lower the poles carefully with a friend, pick the cones, > and raise again. The neighbors think I'm nuts. They think it is some sort After setting the poles up in spring, I really didn't feel like taking each one down a few times for hop harvesting. I ran 1 string (Sisal, 75 lb. strength) to the top of each pole, through an eye bolt and back down again (Ok, I put the string on before the poles went up). This was working fine until two weeks ago. When I visited my hops, (I only see them on weekends) I found my cone-filled-its-going-to-be-a- bumper-crop-almost-ready-for-harvesting-and-its-only-year-two-growth Hallertau in a crumpled heap on the ground. :( :( Down comes the pole, new twine gets threaded onto the old one and the pole goes back up. No visible damage to the plant itself. It seems the string broke at the top of the pole where it went through the eye bolt. I've since purchased small pulleys (for next year). To make matters worse, last weekend I found my Mt. Hood on the ground. Arrgh! This time, two of the bines were a bit crushed. I think they'll be OK, though. Question: What kind of string should be used for hops? The nylon, polyprop, etc. ropes look too slippery. Should I double (or triple) up on the current string? There is no shortage of the stuff (I bought one of the LARGE, 2000 ft., economy sized rolls). Or maybe running 9 bines up one string is a no-no? Mike Sadul msadul at interactiv.com Return to table of contents
Date: Fri, 12 Aug 94 10:56:02 MST From: birkelan at adtaz.sps.mot.com (Joel Birkeland) Subject: Re: Phils Philler(TM) todd boyce <tboyce at bohemia.metronet.org> wrote: > I'd like anyone whom has used a phils philler bottle filler to >give me there impressions on how they though it worked. Good or bad. There >brass, more expensive etc. Do they perform better than anything else >you've personally used, or are you disapointed? I used a Phil's Philler for my first 17 batches, and it seemed to work OK. (The gravity shut-off feature is a nice idea, but it doesn't work. To get around this, you have to use a two-handed method with this filler.) However, it broke apart just before filling batch #18, which forced me to resort to just stopping the flow by pinching the bottling tube. I was amazed to see that I could fill the bottles much more quickly and with much less foaming using this "pinched tube" method than I could using the Phil's Philler. Later, I soldered my Phil's Philler back together, and tried filling some beer bottles with water. I noticed a lot of entrained air in the stream entering the bottles. I guess this could have been due to my repair work, but I doubt it. I think the Phil's Philler is cute, but I won't buy another one. On batches #19 and #20 I used a homemade filler that I constructed from some brass tubing I picked up at the local Ace hardware for about $3. The design isn't perfected yet, but already it works better than Phil's, and in a few iterations I figure I will have a decent filler. Joel Birkeland "Phoenix, AZ: An oasis of ugliness in the midst Motorola SPS of a beautiful wasteland" birkelan at adtaz.sps.mot.com - Edward Abbey Return to table of contents
Date: Fri, 12 Aug 94 13:02:29 -0500 From: jay_weissler at il.us.swissbank.com (Jay Weissler) Subject: How do Chicagoland brewers treat their water? I'm interested in knowing what water treatments Chicagoland full and partial mashers are using for different styles of brew. Specifically, 1) What do you do (if anything)? This includes pre-boiling the mash water, acid or chemical additions, tribal dances, etc. 2) Why? What effect are you looking for, deficiency being corrected 3) Style of brew 4) Mashing method (full vs. partial, infusion,step,decoction). 5) Satisfaction with method, advantages, drawbacks, other comments. Of course, I'm also interested in the opinions of non-Chi-town mashers. I'm just focusing on where I live and know the water best. I'll post a summary. TIA jayw Return to table of contents
Date: 12 Aug 94 14:15:58 EDT From: "Glenace L. Melton" <71242.2275 at compuserve.com> Subject: More on Forfeiture laws - -------- Forwarded Message -------- Subject: More on Forfeiture laws Date: 12-Aug-94 at 10:51 From: Glenace L. Melton, 71242,2275 To: Glenace L. Melton,71242,2275 Gary Meier states that the police must prove in court that property they have confiscated under the forfeiture laws was involved in illegal activity. That is true if the defendant files an appeal. To file an appeal he must post an appeal bond equal to the value of the confiscated property. In the case of the homebrew equipment that would have been reasonable. However, if the cop had coveted the homebrewer's car, say it had been a Lamborghini or Rolls, that could well have been forfeited also. The gentleman in Alabama who gets a thrill out of committing the felony of homebrewing should do it outside his home, if he owns it. If he is renting, his landlord should fear for his property. The theory of the forfeiture laws (as I understand it, and I emphasize that I am not a lawyer and this is based purely on experience and my own reading) is that while a person has inalienable property rights, and the state must go through due process to confiscate any property, property has no such rights and if property is involved in a felony it can be confiscated. This appears to be a reversion to animism, but has been approved by the U.S. Supreme Court, unfortunately. Again, if this seems unAmerican, and it surely is, flame your congressmen. I am sure W VA is beautiful and has wonderful people. So do all the southern and eastern mountains states. But their judicial systems suck. If you want justice you have to get a spotlight. [END] Return to table of contents
Date: 12 Aug 94 15:17:33 EDT From: "William F. Cook" <71533.2750 at compuserve.com> Subject: Hydrometer temperature correction Chip Hitchcock asked about an equation for hydrometer correction. I'm not a chemist, but I am an engineer who deals with water density quite frequently, and here's my solution: Given T in degrees F, the amount to ADD to the hydrometer reading is: deltaSG = -2.6086e-9*T^3 + 2.0441e-6*T^2 - 1.3003e-4*T + 1.0991e-3 Or, if you prefer lookup tables: Temp F Correction Temp F Correction - ------ ---------- ------ ---------- 40 -0.0010 130 0.0130 50 -0.0006 140 0.0158 60 0.0001 150 0.0188 70 0.0011 160 0.0219 80 0.0024 170 0.0253 90 0.0041 180 0.0287 100 0.0059 190 0.0323 110 0.0081 200 0.0360 120 0.0104 210 0.0398 I keep a plot posted on the wall in the brewery, and it seems to work well. The derivation is as follows: >From the "Handbook of Chemistry and Physics", CRC Press, 68th edition, page F-5, an equation for the density of fresh water is as follows: rho = (999.83952 + 16.945176*T - 7.987041e-3*T^2 - 4.6170461e-5*T^3 + 1.0556302e-7*T^4 - 2.8054253e-10*T^5) / (1 + 0.01687985*T) where: rho = mass density of water in kg/m^3 T = temperature of water in degrees C Calculate a table and divide everything by the density at 60^F (15.556^C) to get the specific gravity. Then subtract from 1.000 to get the correction. The fit presented above is good from 32^F to 212^F, and quite close to the numbers provided by the equation in CRC (+/- 0.00003). None of this accounts for thermal expansion of the instument, etc. as pointed out by Manning Martin in #1433, but I believe it is accurate enough for most homebrewing purposes. I'm not sure about it's accuracy above 170^F, as I don't take gravity readings between mash-out and racking cooled wort. I hope this is helpful to someone. Bill Cook HydroComp, Inc. Team Dennis Conner Return to table of contents
Date: 12 Aug 94 20:04:00 GMT From: korz at iepubj.att.com (Algis R Korzonas +1 708 979 8583) Subject: hardness and boiling/chantrelles/Richard's beginner's guide Scott writes: >bacteria, I wouldn't take any chances with *my* wort. In addition, >by boiling you drive off chlorine, chlorophenols (if there are any, >hopefully not) and get rid of permanent hardness. Sounds like three >good reasons to me! I'm sure Scott meant temporary hardness. Permanent hardness is primarily due to Ca and Mg in the water, whereas temporary hardness is due to Carbonates in the water. Boiling high-carbonate water (assuming there is sufficient Ca in the water) will cause some Calcium Carbonate to precipitate out, thereby reducing the overall hardness of the water. I'm sure this is what Scott meant. ********* Henry writes: >With all the rain here in the mid-Atlantic, chanterelle mushrooms are >rather plentiful. I think they'd be better served with beer than as an >ingredient in beer. However, I have heard of a chanterelle licquor. So -- >has anyone out there ever heard of a mushroom beer (that is, one using >edible mushrooms rather than those that get you high. I presume the latter has >been attempted & I really don't want the recipe if it has). Darn... lucky you. Yes, as a matter of fact, I've heard of and tasted chantrelle beer. Randy Mosher made it and basically, if I recall correctly, it was 1 pound of chantrelles, soaked in 1 fifth of vodka for a month (don't recall exactly, but I believe a month is right). Then the liquid is strained off and added to bottles of beer at bottling time. ********* Richard has been posting installments of his "beginners [sic] guide to advanced and all-grain brewing. Someone (sorry) has posted a possible use for this body of work, namely to explain brewing to non-brewers. If this was Richard's intent, then with a few corrections, it would do the job, but if the intent was to teach beginners how to brew all-grain, then it certainly falls short. There is just not enough information on the equipment or detail on the mashing process to get a beginner brewing all-grain. Also, if they are already a brewer, then it should be assumed that they already know much of the info that is presented. Really, I think it's more of a thumbnail description of brewing for non-brewers, not a how-to-all-grain as it was initially presented. One thing that started me off disliking the post was all the emphasis on alcohol in the introduction. Alcohol was mentioned 8 times in the 9 sentances of the introduction. It makes it sound like alcohol is the most important reason for making beer. No mention of economy, quality, better flavor, the pride in creating something yourself or the ability to create beers that are unavailable commecially (either because you live in a beer wasteland or because curry beer doesn't have mass appeal). Also, check the definition of zymurgy. >In ancient times, the only source of sugar readily available was to be >found in the hives of bees. I'm afraid not. Even in ancient times, they realized that they could make (what turns out to be) a fermented beverage from grains. >Warmer temperatures (over 153 degrees Fahrenheit or so) encourage >the type of enzymes, called alpha enzymes, that convert long chains >of starches into medium length chains of sugars, called dextrins, which >don't ferment very well, but are necessary for a well made beer. >Temperatures below that encourage the beta enzymes, which convert >the chains of dextrins into fermentable sugars. In order to get a good >balance of fermentable and non-fermentable sugars, we seek to achieve >a balance of temperature of around 150-153 degrees Fahrenheit. Not quite. The key to higher mash temps making more dextrinous wort is that beta amylase is denatured quickly at higher temperatures (the higher, the quicker). At lower mash temps (148F, 149F, 150F...) both alpha and beta amylase cut starches up into fermentables. At higher temps (158F, 157F, 156F...) beta amylase is quickly denatured and only alpha amylase is left to work on the starches. Alpha amylase is limited in what it can cut up on the starches and thus a less fermentable, more dextrinous wort is the result. Also, the style should dictate how dextrinous the wort should be -- a highly dextrinous Belgian wit would be out- of-style, where a very thin Scotish export would also be uncharacteristic. >Other types of malt, referred to as under-modified, or lager malt, >are of course, less well modified. This means that the malting process >has not proceeded along as far as is the case with the well-modified >malts. Not the malting process, but the germination process has not proceeded as far in undermodified malts, but most malts these days (yes, even lager malts) are fully modified. >The starch tends to settle to the bottom of the tun where it is converted >to sugar and drained away. The grain husks, which tend to float away, >will then settle to the bottom of the tun, forming a filter bed to work in >conjunction with the filtering properties of the slotted PVC pipe. No, the starch and the husks don't really separate, but rather the whole mash is a sort of porridge in which the reactions take place. >away, while new water is allowed to flow through the grains. This >sparge water should be no warmer than 170 degrees, as water hotter >than that will leech out bitter oils and resins from the grains, >potentially ruining an otherwise perfect batch of beer. No again. If you are going to mention the temperature, then you had better mention the pH also. It's the pH and not really the temperature that causes the leeching. And I believe you're thinking of hops when you write "oils and resins" -- what you leech from husks is tannins. >water only serves to dilute the grain bed, resulting in a loss of enzymes. >The other method of introducing heat to the mash is to remove some of >the liquid from the mash. This liquor is heated up, and then returned >to the mash. This process is called decoction mashing, and is a technique >used in program temperature mashing. Decoction mashing (not the only method of program temperature mashing, BTW) involves the removal of the *thickest* portion of the mash, not the liquid. Removing the liquid and boiling it will result in the loss of enzymes that you were worried about losing in the previous sentance. Finally, diluting the grain bed does not result in a *loss* of enzymes. Al. Return to table of contents
Date: 12 Aug 94 20:25:00 GMT From: korz at iepubj.att.com (Algis R Korzonas +1 708 979 8583) Subject: raking/Britain's "best" beer/beer engine Jim writes, regarding rakes running during the sparge: >Well, now we have 6/8 data points from British breweries. Now we need to >get samples from German, Belgian, Swiss and Checz breweries to see what they >do! I have also been asking brewers this question and often the answer is >"I run em every 15 minutes for about 2 minutes then turn em off", or >"I run em a bit in the start, then let em set until halfway through and >sometimes drop the height as the lauter proceeds". I got a paper from >Rich Fortnum who attends the Malting, Brewing & Distilling Science program >at the Heriot-Watt University, Edinburgh, Scotland. In this paper, they >did studies on controlled procedures in Weizen production. One of >the interesting points was the specific detail of height of rakes and >speed of revolution in the lauter tun. If I recall, the rakes were idle >until about 50 mins into the lauter, then they were progressively rotated >faster and deeper for the remainder of the lauter. Just goes to show >different strokes for different brewers/breweries/styles/malts..... Agreed. Actually, now that I'm back to driving on the right and have started sleeping past 3am CDT, I recall that it was 5 breweries (had 7 scheduled, but missed two due to travel delays). I believe that I posted this a few weeks ago, but it is relevant to the current discussion, so perhaps I'll repeat it: in Hough's Biotechnology of Malting and Brewing, he writes that, in general, rakes are necessary for decoction mashing and usually not used for infusion mashes. The reason being, that during the decoctions, all the trapped air gets boiled out of the mash and thus the mash loses it's buoyancy. Theoretically speaking (based on channeling in soil) the ways I could see raking increasing extraction would be: 1. if the mash was extremely sticky either due to glucans, big proteins or being too cool (picture water trying to go through clay) or 2. if the runoff was being taken from localized areas i.e. just from the center or just from a small number of points (let's say it was just from a single point in the middle of a large, wide lauter tun -- there would be pools of relatively stagnant runoff in the corners -- the sparge water would take the path of least resistance and the corners are not on that path). Granted, this is all theoretical and does not account for many factors (mash stiffness, for example). I must admit, however, that I personally, have never made an all-grain wheat beer, never have done a decoction mash, never had a set mash and always resisted stirring the mash during runoff. Perhaps I'm just trying to justify my own biases <-- not good science! >So, Algis, what was *the* best beer on the trip, and did you >return with a beer engine? Given that I was at the Great British Beer Festival but that most of the time I was on my own (i.e. I was not with one or two other tasters so we could share a half pint) I only tasted a fraction of the beers available to me. Nonetheless, I critically evaluated well over 120 different beers and of those the three that stand out as the very best IMO were Jennings Bitter, Gales HSB and Timothy Taylor Landlord (which won Champion bitter). Almost all the ales I tasted were good to excellent, but what made these three the best was their complexity. Many malt and hop flavors intertwined throughout the palate on these beers -- each sip was a new experience, especially the Landlord. Only one beer was judged poor and one undrinkable (Edinburgh's Rose Street Brewpub Auld Reekie 80/- and 90/- respectively) and these were AT the brewery! Return with a beer engine? No, I'm afraid I bought two. Al. Return to table of contents
Date: 12 Aug 94 20:28:00 GMT From: korz at iepubj.att.com (Algis R Korzonas +1 708 979 8583) Subject: thermal air currents/gushers/Anchor Porter yeast guess Erik writes: >When we prepare agar plates for bacterial cultures in the lab we heat the >sterile agar until it is liquid and pour it immdiately into the dishes. >This is done in the presence of a lit bunsen burner which cretes a thermal >air current that theoretically keeps bacteria from falling into the dishes. I've read this before and don't believe that working near a lit bunsen burner can keep bacteria away from your plates. Can someone explain to me why it would? The way I see it is the heat rising from the burner will cause upward air currents in the general vicinity of the work. The rising air must be replaced -- from where? From the other parts of the room. I think that the air currents will draw air (and possibly settled dust/bacteria) INTO the work area from below and from the sides, no? Since the flow is not necessarily going to be laminar (it will swirl) wouldn't it just be better to work in a small, draft-free room? ********** Seth writes: >I'm a newbie homebrewer currently on my third batch. I've used Edme dry >yeast on both the first and third batches, and noticed the same >behavoir (fermentation goes strong for ~1day then just about stops). I >don't have a hydrometer, so I don't know what the gravities are/were. >For the first batch, I bottled it after two weeks. It turned out mildly >carbonated, but the yeast aparently ``woke up'' after two months. On >the final bottles, the dimple in the cap popped out, and the beer was >way over carbonated. It didn't gush on opening, but it was like pouring >foam. What you've got is an infected batch. The primary yeast did it's work in the first day. Either a wild yeast ate the bigger sugars that your primary yeast could not eat or a bacteria cut up the bigger sugars into smaller ones that the primary yeast could then eat. Recheck your sanitation (summer is a tough time to avoid infections, BTW) and possibly consider a different yeast. Edme *used* to have a reputation for having wild yeasts and bacteria mixed right in, but they may have cleaned up their act along with the other dry yeast manufacturers. ********* Dave in Sydney writes: >anyone know if Anchor uses the same yeast for >their Porter as they do for the illustrious Steam beer? I had heard that Anchor had switched from a lager yeast to an ale yeast on the Porter, but that they were dissatisfied with the results and went back to the lager yeast. I don't know if any of these ale yeast batches were commercially sold. However, my suspicion is that if Anchor is using a lager yeast for their Porter, then it's very likely that it is indeed the same as the Steam Beer yeast, which is available as Wyeast California Lager (#2112). Al. Return to table of contents
Date: Fri, 12 Aug 94 14:36:23 -0600 From: Sean.Rooney at uic.edu (Sean Rooney) Subject: hot water kills plants I regularly use the boiling water left over from canning to kill weeds growing in the cracks in my driveway and sidewalk. If you add some salt to the water they don't come back. It's fun to watch the leaves turn bright green as the weeds are cooked alive. Sean Return to table of contents
Date: Fri, 12 Aug 94 15:10:05 MDT From: "Mark B. Alston" <c-amb at math.utah.edu> Subject: Re: That fresh beer flavor/Closed systems/CHEAP Cornelius kegs Teddy Winstead asked: (Related to first question) Is anyone using the closed-system fermenter techniques outlined in the Zymurgy Gadgets issue? This system is based on using one cornelius keg for primary fermentation and carbonation, and a second cornelius keg for lagering, storage, and serving. The argument is that the beer is never exposed to air until it is served. I personally beleive in it, but I'd like to hear from sceptical people as well as those that have tried this to hear what they do or don't like about it. I have been using a corny keg to ferment in for about 10 batches. Here are a few suggestions I have for using the keg in this manner. Contrary to what the Gadgets issue suggests I don't suggest cutting off the long "out" tube. I use a copper end cap and 1" of copper tubing placed over the end of the dip tube to keep from sucking up the yeast sediment I then file some "v" grooves into the dip tube to allow flow to continue if the end cap is sucked onto the dip tube. In this way the keg can still be used as a serving vessel by simply removing the copper tube setup. For a blowoff system I simply remove the poppet from the gas end and remove the valve and spring from a gas quick-connect. Then I attach 4' of tubing to the quick-connect. Many people have warned that you could get a clogged blowoff tube this way, but I have found that if you make certain that no hop leaves make it into the keg that there are no problems with this method. For me the biggest benefits of using this method are the ease of racking the beer into the serving tank, and the ability to drop the yeast out of the beer by placing the fermenter into an ice water bath prior to racking. Furthermore, contrary to popular opinion, the keg is easier to clean and sanitize. I can get my arm into the keg to scrub it clean, which is impossible with a carboy. And sanitiation is simple to achive with a couple of gallons of boiling H2O. YMMV, Mark Alston (c-amb at math.utah.edu) Return to table of contents
Date: Fri, 12 Aug 94 16:24:25 CDT From: MJones at swri.edu Subject: Using Pure Oxygen to Aerate Wort Dear Homebrewers: I recently got a good deal on a medical oxygen tank and regulator. I would like to use pure oxygen to aerate the wort to give the yeast a good head start. The two questions I have are: 1). Can I oversaturate the O2 content of the wort using pure O2? 2). Should I still put a bacterial filter in-line between the O2 tank and wort? Any input would be appreciated. Cheers, Mark Jones mjones at swri.edu Return to table of contents
Date: Fri, 12 Aug 1994 16:01:40 -0600 (MDT) From: DGERTH at LIMS1.LANL.GOV Subject: specific gravity stuff Howdy Folks, Here's some info on specific gravity. It seems to be popping up frequently lately, so I put together a mini FAQ. Any questions or comments, please email me direct at dgerth at lims1.lanl.gov. 1. Specific gravity is defined as the ratio of the mass of a liquid to the mass of an equal volume of pure water, at a specified temperature. Most hydrometers are calibrated (in the U.S., at least) at 60 F, which is 15 5/9 C. Since the density of water decreases from 4 C on up, a factor is required to correct the observed sp. gr. to what would be observed at the reference temperature (There's a few assumptions and other factors, but for all practical purposes.....). This factor can be calculated from data on the weight of 1 gram of water at various temperatures. Using 60 F as the reference temp., these factors are: Temp, F Correction Temp, F Correction 60.0 0.0000 93.2 0.0046 62.6 0.0002 95.0 0.0049 66.2 0.0006 104.0 0.0067 69.8 0.0010 113.0 0.0088 73.4 0.0015 122.0 0.0110 77.0 0.0019 131.0 0.0133 78.8 0.0022 140.0 0.0158 80.6 0.0025 149.0 0.0185 82.4 0.0027 158.0 0.0212 84.2 0.0030 167.0 0.0242 86.0 0.0033 176.0 0.0272 87.8 0.0036 185.0 0.0304 89.6 0.0039 194.0 0.0337 91.4 0.0043 203.0 0.0371 212.0 0.0407 These numbers should be pretty close to those supplied with your hydrometer. Simply add the correction to the observed sp. gr. For temperatures not in the table, you can use (for temps > 60 F only!): factor = 9.933E-7 * T^2 + 1.956E-6 * T - 4.065E-3 This will get you close enough that other errors are predominant. 2. Suspended material exerts an effect on sp. gr.. The effects vary, depending upon the density of the suspended material (including clinging bubbles). To be correct, you should filter or let settle before reading. 3. Always read at the bottom of the meiniscus : | | | | (the bottom of the u's --->) |\_/| |\_/|<-- tube wall | | | | | hydrometer 4. Always push the hydrometer down slightly past its natural float point and spin it to eliminate clinging bubbles. Hope this helps, and pray for me: I'm doing my first all grain batch this weekend! Dan Gerth dgerth at lims1.lanl.gov Return to table of contents
Date: 12 Aug 1994 15:28:54 U From: "Palmer.John" <palmer at ssdgwy.mdc.com> Subject: Corrosion of 304 Stainless Steel Thought I would provide more complete information on the chemistry of stainless steel as it relates to homebrewers. Aiden's post on not using Chlorine Bleach with stainless steel kegs was not Wrong, but it can be used safely if the parameters are understood. Here are the parameters. Corrosion of 300 series Stainless Steel The 300 series austenitic Stainless Steels commonly used for kegs and cooking equipment are very acid resistant. The steel receives its protection from a passive oxide layer that forms on the surface when exposed to air (oxygen). Because acids are oxidizing, acids promote this protective layer. The oxide layer is primarily composed of Chromium oxides with Nickel oxide contributing. Q: Why doesn't this work for aluminum? A: The aluminum oxides are porous to do not prevent exposure of the base metal to the corrosive media. Anodizing is an electro- chemical process that builds up the surface oxide, making it thicker and non-porous. Calphilon Cookware is anodized aluminum. Okay, back to Stainless. The corrosion resistance depends on the chromium. Austenitic stainless is a super saturated solution of chromium and nickel in iron. It is actually a very high temperature phase (arrangement) that has been frozen to preserve the distribution of elements. Austenitic stainless does not like heat. It performs well up to 600F, but higher temperatures cause atom diffusion which causes the properties to change. Compare it to Ice Cream. If you let Ice Cream get soft, then stick it back in the freezer, it will stay much the same. But if you let it melt completely and stick that back in the freezer, you get a frozen puddle which is no longer what you consider Ice Cream to be. Welding is a local melting/freezing process whereby atom diffusion can take place if it is hot enough, long enough. There are time/temperature curves that describe this, but don't lend themselves to ascii. Suffice to say that for Type 304 stainless, five minutes at 600F or above will cause chromium diffusion that will later cause cracking in service. Exposure to the temperatures that cause diffusion is termed as being Sensitized. Type 304L stainless, L meaning less carbon, is more weldable and can spend almost 20 hours above 600F before becoming Sensitized. Most kegs are made from 304L to facilitate the welded construction. What this means to brewers that use high BTU propane burners is that care must be taken to not overheat the kegs while boiling or this sensitization will occur over time. Diffusion is cumulative. Okay, back to corrosion. The corrosion inhibitor is the passive oxide layer that protects the surface. All corrosion is basically galvanic. The electrochemical difference between a metal and a non-metal or two metals in an electrolyte causes electrons to flow and ions to be created. These ions combine with oxygen or other elements to create corrosion products. Now lets say we already have an electrolytic solution containing ions, bleach water. These chlorides are caustic or alkaline and cause the protective oxide layer to deteriorate. If a stainless steel container is completely full of this electrolyte, every surface is at the same electrical potential and nothing happens. But what if there were a deep scratch in the wall, or a rubber gasket against the steel creating a crevice? Well, these areas can become electrically different from the surrounding area and a galvanic cell can be created. Inside the crevice, on a microscopic scale, the chlorine ions can combine with the oxygen, both in the water and on the steel surface, to form chlorite ions, thus depleting that local area of oxygen. If the bleach water is still, no circulation, then that crevice becomes a tiny highly active site relative to the more passive stainless steel around it and corrodes. This is known as Crevice Corrosion. The same thing can happen at the surface if the keg is only half full. In this case, the steel above the waterline is in air and the passive oxide layer is stable. Beneath the surface, the oxide layer is at a different potential and less stable due to the chloride ions. Now the crevice is represented by the waterline. Stable area above, less stable but very large area below, crevice corrosion occurs at the waterline. Usually this type of corrosion will manifest as pitting or pinholes. The mechanism described is accelerated by localization so a pit is most often the result. A third way that chlorides can cause corrosion of stainless is by concentration. This mode is very similar to the crevice mode described above. By allowing chlorinated water to evaporate and dry on a steel surface, those chlorides become concentrated and change the electrical potential of the surface at that site. The next time the surface is wetted, corrosion will immediately take place, creating a shallow pit. The next time the keg is allowed to dry, that pit will probably be one of the last sites to evaporate, causing chloride concentration again. At some point in the cycle life of the keg, that site will become deep enough for crevice corrosion to take over and the pit will corrode through. Given the above information, knowing our enemy as it were, we can develop usage practices to ensure that our precious stainless is not attacked and pitted by the use of bleach as a sanitizer. 1. Do not allow the stainless steel vessel to sit for extended periods of time (hours, days) filled with chlorine water. 2. Fill the vessel completely so that all surfaces are at the same potential. 3. Swirl the water once in a while to eliminate local concentration/ de-oxidation. 4. After the 20-30 minute soak for sanitizing, rinse the keg with preboiled water to prevent evaporation concentration and either dry it completely with a towel (if storing) or fill it with beer. These simple practices will preclude chlorine induced corrosion. John Palmer - Metallurgist for International Space Station Alpha McDonnell Douglas Aerospace, Huntington Beach, CA Return to table of contents
End of HOMEBREW Digest #1501, 08/15/94