HOMEBREW Digest #4334 Thu 28 August 2003

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  Re: Bubbles, Tiny (and big) Bubbles ("Fredrik")
  Re: Organizing All This Stuff ("Mike Sharp")
  build your own hop back (Alan McKay)
  RE: Hop Back / Percolator (Bill Tobler)
  Low Carb Beer ("Dan Listermann")
  Celiac Sprue ("Dan Listermann")
  Organize brewing gagets.. ("Mike Eyre")
  RE: Hop Back / Percolator (Kevin McDonough)
  Sulfite in wine, O2 vs O,nitrogen sensors, CO2 danger in manufacturing and breweries ("Dave Burley")
  Celiac Sprue (Steve Tighe)
  re: you've got mail (Scott Alfter)
  Re: 1st all grain brew & resultant questions (Jeff Renner)
  Brewing Gear and Convoluted Copper Tubing ("Chip Stewart")
  organizing brewing crap ("Jay Spies")
  Party ball (tidmarsh)
  Mash temp and yeast for a Foghorn Clone ("Charley Burns")
  plastic bottle caps. ("John Sarette")
  New Freezer - Operation Question ("Steven P. Bellner")
  Dr. Cone Responds-Mike Zapolski-Part 1-Questions ("Rob Moline")
  Dr. Cone Responds-Mike Zapolski-Part 2-Answers ("Rob Moline")
  Single yeast establishments ("Chad Stevens")
  Dr. Cone's Final Comment-Gump Reports ("Rob Moline")
  Yeast Adaptation (Newbie Question) (Alexandre Enkerli)
  Electric Kettle Control (yax)

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---------------------------------------------------------------------- Date: Wed, 27 Aug 2003 07:09:55 +0200 From: "Fredrik" <carlsbergerensis at hotmail.com> Subject: Re: Bubbles, Tiny (and big) Bubbles - ------------------------------ > /Fredrik is counting CO2 bubbles in the airlock. I did this at the beginning > of my brewing career also, so I understand. > > One thing you must remember is that CO2 is soluble in water/beer and this will > skew your results, as the fermentation can proceed for a while before any > bubbles come out. Temperature is a problem to be accounted for, as solubility > of CO2 is temperature dependent. > > But the largest variable and least accountable for variable is the fact the > CO2 in a water system is slow to come to equilibrium ( and thank goodness!) > were it not, we would get a shower of beer every time we opened a bottle. > > You could try agitation during fermentation or other mechanical means to bring > the CO2 to equilibrium, but this has apparently ( IOW , jury is still out in > my book) been shown to have adverse effects on beer quality. > > Point is, bubble counting is not a good measure of fermentation rate until the > fermeting fluid is saturated and not even then due to the non-equilibrium > release of CO2. > I agree with Daves critics on all points. Maybe I should wait defending the bubble method until I have acquired some more statistics as I would have some more definite arguments, but I just want to defend the poor bubbles(!!) here because though it's not without complications, it is certainly not useless, it can in fact be quite useful IMO :) There is a problem if someone puts equality between fermentation rate and bubbling rate, this would be a mistake I agree. Since the relation is not as simple as a linear correction I agree it may be good to point this out if anyone else wants to interpret bubbles. The relation is dynamical and not static, thus you could say it's "complicated" and you probably need a little more than a simple pocket calculator to correct for it. I will use some differential equations to relate them. I do belive that the relation between the fermentation rate and the bubbling rate is fairly predictable and managable at least to the rough extent required for me. I think the complications are a bigger problem if they are ignored. I agree though that the trickiest part is probably the activity of nucleation sites for bubbles. I intend to account for ambient temperature and pressure, and there are also alot of wort and fermentor specific paramters, one would be the nucleation activity, probably beeing promoted by for example trub. This do gets complex with many variables and parameters. I hope to extend the logger with a temp and pressure channel later on to improve this. There may also be a variation of bubble size, but I belive neither this fatal, though a complication. But time will show. On short timescale bubbling is random, so on the bubble to bubble timescale it's nothing but meaningless noise, but on a slightly larger timescale the variations get more significant. At least if I speak for myself, I think with the correct interpretations the bubble counter gives me data with an accuracy sufficent for my hobby based "brewing research". It can never compete with an expensive fermentation lab and it was never the idea and the comparasion is not really fair. The idea for me was a quick/dirty/cheap means to track my fermentation in an automated manner and to a better extent that just make hydrometer readings. And so far it seems to do the job. Hydrometer readings are excellent as such, the problem as it seems to me is that it normally gives you just two datapoints, FG and OG. I don't anyone would make thousands of manual gravity readings on a batch. This bubble counter idea seemed like a good idea to me. Not perfect, but the best I could think of at the moment and so far I am not dissapointed. The accurate interpretation requires input of ambient pressure and temperature. Perhaps there is a more clever way to track fermentation that doesn't mean byuing expensive lab stuff, but I didn't think of anything else so far. I don't look at bubbles like waste, I like to look at it as information coming out of there, although encoded into a noisy time stream of bubbles. My motivation lies on the firm belief that no matter how complex and noisy bubbles may seem, the information in that stream is wortwhile if just properly decoded. Once I make some more progress and things start to get more coherent I'll put a bubble page page up for this for anyone to judge for themselves. /Fredrik Return to table of contents
Date: Wed, 27 Aug 2003 00:16:04 -0700 From: "Mike Sharp" <rdcpro at hotmail.com> Subject: Re: Organizing All This Stuff Dave Larsen wonders how we organize All This Stuff "That got me wondering what everyone else does, so I thought I'd pose the question: How does everyone organize all their brewing crap?" My organization was horrible until I broke down and went to Home Despot and bought a real nice 2-door white melamine storage cabinet on sale. It's about 6 feet tall, and 4 feet wide. I've set it up so my conical fermenter sits in the lower right compartment, shelves on the lower left hold supplies, gadgets and the large shippers scale. The top compartment is full-width, and it's the "laboratory". It holds both mag stirrers, the smaller scales, glassware, colorimeter, etc. I mounted some PVC pipe pieces to the inside top of the cabinet. My thermometers and hydrometers slide into these, and are well protected. My kettles sit on top of the cabinet. The inside of the cabinet is wired for power (to run the instruments and mag stirrers) and the lower right fermentation compartment has a thermostatically controlled heater for winter fermentation. It cost something like 70 or 80 bucks. I have a separate industrial shelving unit 8 feet high, with 4 ft by 2 ft steel shelves that holds all my cooperage, and the stuff that won't fit in the cabinet. The brewhouse itself is mobile. My garage is still a disaster, but my brewing cabinet is very organized! Regards, Mike Sharp Return to table of contents
Date: Wed, 27 Aug 2003 07:09:41 -0400 From: Alan McKay <amckay at neap.net> Subject: build your own hop back Here is my old design for a hop back. Our club is having a hop back building party soon and I'll take some pictures to put up because my new design is a lot better http://www.bodensatz.com/staticpages/index.php?page=20020429191318951 - -- http://www.bodensatz.com/ The Beer Site "Life begins at 60 - 1.060, that is" - Denny Conn Return to table of contents
Date: Wed, 27 Aug 2003 06:24:19 -0500 From: Bill Tobler <wctobler at sbcglobal.net> Subject: RE: Hop Back / Percolator Rodolf asked about Hop Backs and Percolators. More Beer carries Hop Backs. Open the link below and then click on "Weldless kits & kettle Accessories. Just a satisfied customer. http://www.morebeer.com/ I have a old percolator to make coffee in. Not sure how you would use one to make beer. If there is a piece of beer making equipment called a percolator, I don't know about it. I'll keep tuned in. Bill Tobler Lake Jackson, TX (1129.7, 219.9) Apparent Rennerian Return to table of contents
Date: Wed, 27 Aug 2003 09:09:04 -0400 From: "Dan Listermann" <dan at listermann.com> Subject: Low Carb Beer <"Don Howard" <donchoward at comcast.net> < Is there a more complicated but doable way for a biology/chemistry challenged homebrewer? > This might be counter intuitive and go against a lot of published common wisdom, but you get low final gravities, hence low carb, beers by using a lot of sugar. I have brewed a beer that was 75% cane sugar and 25% DME. It was low carb and, while it didn't taste like much, it did not have the cidery flavor that a lot of people will tell you that it should have. A 66% corn sugar beer I brewed just took third in its category at the total 156 entry Beer and Sweat Competition Saturday. These beers should be given a dose of yeast nutrient because they may not ferment out completely because of poor yeast reproduction due to the low level of nutrient in the wort. Lack of nutrient has not shown itself to cause the cidery flavor, that flavor is strongly associated with old, stale extract. If you want to try this yourself, I recommend using LME that you know to be fresh, DME or all grain. I would hesitate to do this with canned extract unless the "Use By" date is 1.5 years off. Dan Listermann Check out our E-tail site at www.listermann.com Free shipping for orders greater than $35 and East of the Mighty Miss. Return to table of contents
Date: Wed, 27 Aug 2003 09:15:01 -0400 From: "Dan Listermann" <dan at listermann.com> Subject: Celiac Sprue AJ <ajdel at cox.net>A colleage came to me and asked if I as a brewer could do anything to help her alleviate the beer related aspects of his daughter's plight - she suffers from celiac sprue (often described as an intollerance to wheat gluteins but barley hordeins are equally problematical). > We sell a kit that makes a mead that is a good fake of beer using hops and corn derived malto dextrin. While it may not fit a style necessarily, anyone drinking it blind will instantly recognize it as beer. Dan Listermann Check out our E-tail site at www.listermann.com Free shipping for orders greater than $35 and East of the Mighty Miss. Return to table of contents
Date: Wed, 27 Aug 2003 09:32:17 -0400 From: "Mike Eyre" <meyre at sbcglobal.net> Subject: Organize brewing gagets.. hatever I use, I need to be able to carry, push, pull or roll out into the kitchen on brew day, but also be something I can easily stuff in a closet somewhere when not in use (one day a month the kitchen belongs to me, the rest of the time it belongs to SWMBO). That got me wondering what everyone else does, so I thought I'd pose the question: How does everyone organize all their brewing crap? -!-------- For me, that was the easiest part.. I took over an entire room of my house! We moved into a new house a couple years ago and since it's just me and the wife right now, that left 2 spare rooms.. So one is a guest room, and the other is "the beer room" as she calls it. ;) With the thoughts of a nursery swirling around in her head, this maybe short lived.. But I'll be damed if I don't have that entire room packed with kegs, mash tuns, bottles from the floor to the ceiling, and so forth.. I have no idea what I'm going to do when I'm 'evicted' from there.. Mike Return to table of contents
Date: Wed, 27 Aug 2003 10:59:38 -0400 From: Kevin McDonough <kmcdonou at nmu.edu> Subject: RE: Hop Back / Percolator Beer, Beer, and More Beer <http://www.morebeer.com/> now sells a hop back, with various configurations of fittings/connections. Their one with 1/2" FNPT fittings is $79. They go up from there, depending if you get brass quick disconnects, thermoplastic QDs, or sanitary fittings to be used with clover clamps. Simply type in hop back (two words) in their search window. Kevin Return to table of contents
Date: Wed, 27 Aug 2003 12:16:06 -0400 From: "Dave Burley" <Dave_Burley at charter.net> Subject: Sulfite in wine, O2 vs O,nitrogen sensors, CO2 danger in manufacturing and breweries Brewsters: Larry Suarez asks an off topic question about adjusting sulfites in wine before bottling. Titrets ( a commercial product from the hobby store) will allow you to determine sulfites. Easy answer ( without getting into pH and and free vs bound SO2 and stuff) is add 1/8 tsp of K meta bisulfite to each 5 gallons of wine ( ~30 ppm SO2 under normal conditions) . Make up a solution of 1/8 tsp Kmetab'ite in 125 mls of water and add 5 mls ( tsp) to each 750 ml bottle before adding wine. This prevents "bottle sickness" due to oxygen incorporation during bottling. Dsicussion to my e-mail off line, please - ------------------------ Ron Laborde and others, Oxygen's molecular symbol ( in which state it exists for all practical purposes) is O2. NOT O. O would refer to and be called "Nascent Oxygen" or "atomic oxygen" O2 is correct for our purposes. - ------------------------ Pete, Don't you mean you will see <oxygen> sensors where nitrogen ( and other gases) are stored? Nitrogen makes up 80% of air. - ------------------------ Without thinking about it, a vintner friend of mine once lowered himself into a freshly emptied fermenter and had the good sense to realize he couldn't breathe and being young and athletic was able to scramble out before dying. Often in chemical plants and wineries and breweries multiple deaths occur in the same incident since friends and workers go into the same vessel quickly, without clearing it, to rescue a compatriot. And then there was O'malley who drowned at a Guinness brewery when he fell in the bottling tank. He did have to get out three times to have a pea before he succumbed, though. Keep on Brewin' Dave Burley Return to table of contents
Date: Wed, 27 Aug 2003 09:50:15 -0700 (PDT) From: Steve Tighe <steve_tighe at yahoo.com> Subject: Celiac Sprue Date: Tue, 26 Aug 2003 19:18:08 +0000 From: AJ <ajdel at cox.net> Subject: Sprue A colleage came to me and asked if I as a brewer could do anything to help her alleviate the beer related aspects of his daughter's plight - she suffers from celiac sprue (often described as an intollerance to wheat gluteins but barley hordeins are equally problematical). I seem to remember this subject coming up here before but a quick look at the archives wasn't very helpful. Does (or has) anyone here brewed a beer (successful or unsuccessful) for people who suffer from this disease? I so, can you describe it, give a recipe etc.? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Celiac Sprue is an allergy to gluten, which is found in barley, wheat, and most other grains (and lots of other stuff). I have a friend with this, and his beverage choices are pretty much limited to wine, rum, potato vodka, and ta-kill-ya. There was an article in Zymurgy about a year ago about brewing gluten-free beer. Basically, you need to select from the very few gluten-free grains (and of course I can't remember what they are, but I guarantee your friend knows). The biggest wrinkle is you'll need to malt the grains yourself, unless you could somehow find malted versions of these grains (which the article suggested you wouldn't). There was also a concern about yeast, since yeast are propagated in a gluten-containing medium. I think they suggested dry yeast. In any event, yes you can brew "beer" that is gluten-free, but probably not with materials you usually buy in the homebrew shop. Steve in Berkeley Return to table of contents
Date: Wed, 27 Aug 2003 10:14:24 -0700 From: Scott Alfter <scott at alfter.us> Subject: re: you've got mail On Mon, 25 Aug 2003 08:20:57 -0700 (PDT), Rama Roberts <rama at sun.com> wrote: > On a good note, Pat and I have been discussing a fix that will help limit > future spam. The HBD archives expose email addresses as Mailto links- > perfect for "scrapers" to harvest them and pass them on to spammers. Our > plan is to convert those addresses, for example: > billgates at microsoft.com > to > billgates AT microsoft DOT com A better form of email obfuscation would be to replace the individual characters with their character-entity equivalents. Here's a website that converts email addresses you feed to it: http://alicorna.com/obfuscator.html It turns foo at bar.com into something like this: &#102;&#111;&#111;&#64;&#98;&#97;&#114;&#46;&#99;&#111;&#109; Browsers will display it properly, and if you click a mailto link, it'll work. Address harvesters, though, aren't smart enough to decode the character entities back to plain text. Here's an example of a webpage with a bunch of obfuscated addresses: http://snafu.alfter.us/officers.shtml Creating some code to generate obfuscated email addresses would be trivial: #include <stdio.h> #include <string.h> int main (int argc, char **argv) { int i, j; for (i=1; i<argc; i++) { for (j=0; j<strlen(argv[i]); j++) printf("&#%d;",argv[i][j]); printf("\n"); } return 0; } Call it with the addresses to obfuscate as parameters (separated with spaces) and it'll spit out obfuscated addresses (one per line). Scott Alfter scott at alfter.us Return to table of contents
Date: Wed, 27 Aug 2003 13:24:01 -0400 From: Jeff Renner <jeffrenner at comcast.net> Subject: Re: 1st all grain brew & resultant questions Chet Nunan <katjulchet at yahoo.com> in Churubusco IN writes: >1.079, FG approx. 1.009. ...I know this is a strong beer, but I >get a horrible hangover from it! A 1/2 gal growler >over an evening is a guaranteed head pounder. I don't think you need to look any further than the amount of alcohol to explain your headaches. While you might have higher alcohols (fusels) from your fermentation temperature or other reasons, there is some dispute as to whether or not these actually cause headaches and/or hangovers. The calculator at http://realbeer.com/spencer/attenuation.html#alcohol gives 8.2% ABV for your beer, which means that in that 1/2 gallon growler, there is 5.25 oz (155 ml) of alcohol. That's the equivalent of nearly nine standard drinks (defined as 12 oz. beer at 5%, 5 oz. wine at 12%, 1.5 oz. spirits at 80 proof/40%). Another way of looking at this is that it is the equivalent of a half bottle of vodka. That would give me a headache! Jeff - -- Jeff Renner in Ann Arbor, Michigan USA, JeffRenner at comcast.net "One never knows, do one?" Fats Waller, American Musician, 1904-1943 Return to table of contents
Date: Wed, 27 Aug 2003 13:43:19 -0400 (EDT) From: "Chip Stewart" <Charles at thestewarts.com> Subject: Brewing Gear and Convoluted Copper Tubing On Tue, 26 Aug 2003, Tucson Dave Larsen Inquired: > > How does everyone organize all their brewing crap? Dave - I can't recommend enough the baker's rack that I picked up from Costco for about $70. Not only do I store everything on it, but I even use it as the stand for my RIMS system - I actually brew on it! When I'm done, I just wheel it out of the way. I store all the misc. brewing stuff in plastic storage bins that store on the shelves. I have some older photos of it on my web site at http://Charles.TheStewarts.com/brewing/ but have since added a 10 gal. hot water heater on top (modified to produce 170F water) for sparging. On another topic, I'd like to build a counterflow chiller and a hopback. I'm thinking of nesting the hopback inside the chiller to save space. Anyhow, I'd like to use the convoluted copper tubing inside of clear tubing for the chiller. Anyone know of a source for the convoluted tubing? Chip Stewart Charles at TheStewarts.com http://Charles.TheStewarts.com Support anti-Spam legislation. Join the fight http://www.cauce.org Return to table of contents
Date: Wed, 27 Aug 2003 14:08:38 -0400 From: "Jay Spies" <jayspies at citywidehomeloans.com> Subject: organizing brewing crap Hey all - I use an old 6 drawer highboy dresser that was sitting unused in the basement. Lets me split up all my stuff into themes (hoses in one drawer, kegging stuff in another, etc) and it keeps the dust off of it all. I'll bet the majority of readers here have at least one piece of sad lonely furniture in their basement like this. Put it to use! Jay Spies Charm City Altobrewery Baltimore, MD Return to table of contents
Date: Wed, 27 Aug 2003 16:05:22 -0400 From: tidmarsh at bellsouth.net Subject: Party ball Greetings, all-- I've recently acquired from a non-brewing friend a commercial beer sphere/party ball container. I've done a search of the archives and seen that in the past parts were available to reseal these containers after refilling, but the references date back nearly a decade, so I wonder if any such products are still available. I did notice one post from 1990 that described sealing the vessel for conditioning with a wired-down rubber stopper that was removed to allow the tap/pump to be reused, albeit with a less than perfect seal. Does anyone know of a source for parts to re-use a beer-sphere? Seems just the thing for a friend's annual homebrew party--the contents will be consumed in a sitting, and no transportation of CO2 tanks. Tidmarsh Major Tuscaloosa, Ala. Return to table of contents
Date: Wed, 27 Aug 2003 13:24:55 -0700 From: "Charley Burns" <charleyburns at sbcglobal.net> Subject: Mash temp and yeast for a Foghorn Clone I'm ready for my next attempt to try and clone old foghorn. This time I'll stick with northern brewer hops all the way through, even though Michael Jackson thinks they use some cascade. I used cascade last time but the gravity was so high (1.115) that everything else was thrown off. I lost my notes so I don't know what yeast it was, but it was probably wyeast 2112 (lager yeast masquerading as an ale yeast). Assuming 2-row or pale ale malt for 90% and 10% crystal, what is recommended mash temp and which yeast is recommended? Should we go for a low mash temp (~147-150F) and a low attenuating yeast or a higher mash temp (~155-160) with a more aggressive yeast? Seems like both methods would leave us with a high gravity and big bodied beer, I'm just wondering which one would taste the best? A low attenuating yeast would leave more sweetness (I think) while a higher mash temp would give us body (dextrins) without the sweetness. Any comments or suggestions? Charley Burns Return to table of contents
Date: Wed, 27 Aug 2003 17:14:00 -0500 From: "John Sarette" <j2saret at peoplepc.com> Subject: plastic bottle caps. Scott Cortney wants to cap clean empty beer bottles. I can help in his quest for plastic caps - ----But these would be very handy for keeping empty, cleaned and sanitized bottles for your next brewing ession. ----- I take plastic caps from 20 oz water and soft drink bottles cut them from the bottom (open side) with a cross and they will snap onto a beer bottle. I sanatize them in bleach at the same time I do the bottles, let them both dry and cover the bottles unrinsed. when its time to bottle I rinse the bottles in the dish washer. It works fine and there is a never society of ours. John Duluth of the North - --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.512 / Virus Database: 309 - Release Date: 8/19/2003 Return to table of contents
Date: Wed, 27 Aug 2003 18:33:12 -0400 From: "Steven P. Bellner" <sbellner at chartertn.net> Subject: New Freezer - Operation Question My beer freezer was one of the casualties of I lightning strike I experienced earlier this month, and my insurance company has agreed to replace instead of attempt a repair. I have ordered a Whirlpool 20 cuft chest freezer which was about the same size as the defective unit. I used the auxiliary thermostat to run the freezer at 38 F like so many people do, and until the damage occurred, it ran like a charm. I mentioned to the appliance sales rep the intended use for the freezer, and he immediately stated I need to have a refrigerant heater timer installed on the unit before I connect up the external thermostat. He said it is essential to use one of these to extend the life of the compressor. I have never heard of such a device. Is this a line of bull, or is this device needed perhaps because of the use of the new types of refrigerant? I have heard of individuals that own GE freezers that cannot use them in their garages because of external temperature problems in the winter that causes the compressors to stop pumping. I wonder if this is a similar phenomenom. Steven P. Bellner sbellner at chartertn.net Return to table of contents
Date: Wed, 27 Aug 2003 19:25:29 -0500 From: "Rob Moline" <jethrogump at mchsi.com> Subject: Dr. Cone Responds-Mike Zapolski-Part 1-Questions Dr. Cone Responds-Mike Zapolski-Part 1-Questions First, I'd like to thank Dr. Cone for sharing his valuable time, experience, and knowledge with the HBD organization. My yeast related questions are as follows: 1) Cold Pitching, Why does it seem to work? In certain brewing forums there has been much discussion related to cold pitching yeast into ale worts. Basically, about a pint of yeast is harvested from the primary of a brew batch and stored in a sealed container at refrigerator temperatures (abt 45F). At some later time (perhaps as long as 1-2 months), that yeast is pitched directly from the refrigerated container into a new batch of sweet wort at 70-75F. Based on my experience (and observations) this method works quite well, and appears to reduce lag times (from 1.5 to 4 hours). Can you help us understand why the cold pitching process works? Or have we just been lucky? 2) Mid-Fermentation Nutrient Additions - Are there any advantages, or disadvantages, that may occur by adding yeast nutrients to a beer (or wine) after fermentation has begun, but before the mid-point between the OG & TG? 3) What are the differences between yeast nutrients, extracts, hulls, and energizers? What does each product do to facilitate fermentation? At what stage of the brewing proces should they be added to be most effective? Under what circumstances should one use each of these products [what should the brewer look for as an indicator], and what might be a typical amount added to a 5 gallon batch? Is there a product that combines these individual items into a single overall yeast "Superfood"? 4) For a given ale yeast type, does controlling ale fermentation temperature in the 60-68F range have a noticeable affect on the resulting beer's flavor? If so, which ale yeast types are most sensitive to fermentation temperature? 5) What factors (that the brewer might be able to control) influences yeast attenuation? For example, if an ale yeast has an optimum temperature range of 68-73, will holding the primary temperature at 68F yield a better attenuation, than at 73F? Thank you, Mike Zapolski, Sr. - --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.512 / Virus Database: 309 - Release Date: 8/19/2003 Return to table of contents
Date: Wed, 27 Aug 2003 19:28:13 -0500 From: "Rob Moline" <jethrogump at mchsi.com> Subject: Dr. Cone Responds-Mike Zapolski-Part 2-Answers Dr. Cone Responds-Mike Zapolski-Part 2-Answers Mike, 1. I have not seen any studies done using this protocol. If I had to take a guess it would be centered around the Trehalose content in the yeast cell. Trehalose seems to be an all around stress related factor. Almost immediately upon the cold storage of the yeast, trehalose begins to build up to help the yeast to adapt to its new environment. Upon pitching this stress factor assists the yeast to adapt to its new environment; warmer temperature and higher osmotic pressure. If the pitching yeast is allowed to warm up for any appreciable time before pitching the carbohydrate reserve, trehalose being one of them will be quickly used up as an energy source. The yeast would then take a longer time adapting to its new environment in the wort thus increasing the lag phase. Something similar happens when using Active Dry Yeast. The factory builds into each yeast cell an abundance of the stress factor; trehalose. Our recommendations is to rehydrate the yeast in warm water and pitch into the wort (or must) within 30 minutes, because the yeast will begin to metabolize its carbohydrate reserve including trehalose immediately upon reactivation and weaken the yeast if it is not in the presence of a new supply of energy. It will have also used up the stress factor that would have assisted it in adapting to the new osmotic environment. I am sure that there is more to the explanation than I have given. 2. Yeast respond to a fresh source of nitrogen through out its growth phase and early pert of the stationary. The sugar transport systems have a very short life(2+ hours) and enzymes involved need replenishing and a supply of nitrogen. So an incremental feeding is ideal especially to minimize H2S production. This is ideal and begins to be a factor as the O.G increases. With a well mashed wort a low gravity would probably not benefit from this. A high gravity fermentation would definitely benefit. There are other things involved in incremental feeding. All the nutrients up front results in an increased growth of yeast with a lower level of protein when it reaches the stationary phase. Incremental feeding restricts the initial growth but increases the yeast protein level. The higher protein level in each cell increases the fermentation rate and protects the cell against alcohol toxicity near the end of fermentation. Again, this is only beneficial to a higher alcohol fermentation. If you have the analysis of the wort available you can add the exact amount of nutrient. You will need to work with the nutrient supplier. Usually I begin with 1-2 pounds of the product per 1000 gallons(0.5 -1.0 gram / gallon)of wort. That is a safe range to start with. You can go up or down on the next batch according to your evaluation of the current batch. 3.Yeast nutrient is anything that the yeast needs for a healthy growth and to stay alive during the stationary phase; sugar, useable nitrogen (FAN), minerals, trace elements, vitamins and oxygen. A well balanced nutrient like Fermaid K will supply these requirement. Most all malt wort contains a well balanced diet for low gravity fermentations. Sometimes minerals like zinc and magnesium are on the short side. It is when you move up to higher O.G and higher cereal adjuncts addition that added well balanced nutrients need to be considered. Extracts are concentrated extractions of malted barley (malt extract) or autolyzed yeast with out the cell wall. Malt extract, as you get in a kit, makes a very good beer. Many of the useable nitrogens are bound up by the Maillard reaction and are not available to the yeast. Yeast extract contain most of the nutrients that the growing yeast require. However you are limited in the amount that you can use. Above a certain level, you may begin to detect it in the flavor of the beer. Yeast hulls are my favorite. It is probably the best balanced source of nutrient but can be used in a limited amount before you detect it in the finished beer. Lallemand yeast hulls are cell walls loosely separated from the cytoplasm of well autolyzed yeast. These cell walls contain well digested protein that is high in available nitrogen. It also contain lipids that are necessary for yeast growth and protection against alcohol toxicity. Lipids are what you produce when you add oxygen to the fermenting wort. Diammonium phosphate is an excellent, cheap source of available nitrogen for the yeast. You have to evaluate it carefully for flavor and aroma profile if you use it as a sole supplement. Enegizers is a name that could include any or all of the above. Many distributors have their own formula. Fermaid K is a well balance yeast nutrient that was formulated based on many years of experience of yeast production. There are two new products that have come onto the market recently. They do not replace the need for Fermaid K but augment it: GO-FERM is a product that is used in the rehydration water (not in the wort or must) for Active Dry Beer and Wine yeast. It maintains the vitality of the yeast through out the entire fermentation. This becomes important in higher gravity brews. Servomyces offers a biological source of zinc to the yeast. The biological source seems to make it more available for the yeast. 4. If all other factors are the same, you should be able to tell the difference in fermenting ale at carefully controlled variations in temperature. Variations in the malted barley, mashing and pitching yeast from batch to batch can mask any differences that you would have when comparing different fermentation temperatures. Very high alcohol fermentations where alcohol toxicity is involved, cooler temperature near the end may be needed for full attenuation. 5. Attenuation or the conversion rate of all the fermentable sugars to alcohol (plus by-products) is directly related to temperature. So the higher the temperature the faster should be the attenuation. Flocculating after attenuation is primarily controlled by the yeast strain itself. However, excessive re-pitching and acid washing is detrimental to the hydrophobicity (flocculation) of the cell wall. A deficiency in minerals such as calcium adversely effect the flocculation properties of the yeast. Clayton Cone - --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.512 / Virus Database: 309 - Release Date: 8/19/2003 Return to table of contents
Date: Wed, 27 Aug 2003 18:37:18 -0700 From: "Chad Stevens" <zuvaruvi at cox.net> Subject: Single yeast establishments Rama & Y'all, I once had your same disgust with commercial establishments using only one yeast for all their brews until I started really looking into the issue. Remember, it takes only one living yeast cell to reproduce and contaminate another yeast culture. On a large scale, it is impractical for commercial establishments to use more than one strain. Contamination would result as different batches passed through various equipment. You would in essence, have to make two entirely separate breweries in order to use two different strains on a continuing basis. Yes there are some small establishments (some brew pubs for example) that are able to deal with multiple strains but they aren't trying to keep the same pure strains going through years of production. Rather, they must re-purchase base strains periodically to maintain purity and as a result are decreasing their margin. I guess as homebrewers, not trying to make a milk-cow of our muse, we are fortunate in that we are afforded the luxury of picking a new strain for every batch. For what it's worth, Chad Stevens San Diego Return to table of contents
Date: Wed, 27 Aug 2003 23:13:05 -0500 From: "Rob Moline" <jethrogump at mchsi.com> Subject: Dr. Cone's Final Comment-Gump Reports Dr. Cone's Final Comment-Gump Reports Folks, As we wrap up a successful session with Dr. Clayton Cone and a Fortnight of Yeast, I would like to personally thank Dr. Cone, Dr. Fischborn, Dr. Waldrop, and Dr. David Logsdon. Your collective generosity builds bridges of knowledge...and will continue to do so as the info is preserved on the HBD and the Lallemand website.... As far as the questions...WOW, what an impressive and thought provoking collection. The questions posed by the HBD to Dr. Cone have been brilliant and can only hint at the level of expertise apparent in the HB world. By my calcs, all has been answered...if anyone has any that were posted within the session that we have missed, please let me know. Thank you, brewers and brewsters. I can't disagree with a private e-mail comment from Fred Nolke of Anchorage, Alaska..."It's the highest and best use of the HBD." And we owe it all to Clayton Cone. Cheers! Gump P.S. Fredrik, Don't let your donkeys eat your spent grain! (If you don't know, please ask!) Rob, I would like to thank all the participants in the question and answer session during the past two weeks. I have enjoyed the experience. It has been a learning curve for me. My old mind is spinning. It is always of interest to me as to what technical information is not getting to the home beer (and wine) maker or is not being understood and needs to be addressed in a better way. I would also like to thank Drs. Tobias Fischborn and Forbes Wardrop at Lallemand Research Center for their able assistance. There is usually no one answer when it comes to brewing and wine making. There are opposing views on all aspects of fermentation. I hope that my answers will open a dialogue that we can continue to respond to. See you on the Lallemand website. Clayton Cone "The More I Know About Beer, The More I Realize I Need To Know More About Beer!" - --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.512 / Virus Database: 309 - Release Date: 8/19/2003 Return to table of contents
Date: Thu, 28 Aug 2003 00:34:02 -0400 From: Alexandre Enkerli <aenkerli at indiana.edu> Subject: Yeast Adaptation (Newbie Question) In a query to Dr. Clayton Cone, I said the following which I admit might not make that much sense: "We're told yeast will adapt to the medium, at least for scale." This is due to my very limited knowledge of yeast but I'm glad we got an interesting reply on the subject of yeast adaptation. Just to clarify (and hopefully get a better understanding), what I meant was about progressively ramping up starters. I thought the reason we can't just use a very large starter right at first was that yeast adapts somewhat to the wort volume. Sorry about that. Return to table of contents
Date: Wed, 27 Aug 2003 21:45:30 -0700 From: yax <yax75 at shaw.ca> Subject: Electric Kettle Control What is a good way of controlling your boil in an electric kettle? I was thinking about using just a stove rheostat, or else using two switches in line of the element. With both switches on 240 V would be supplied and with just one switch on only 120 V would be supplied. I have heard of some people using PID controllers, but this seems like overkill. Any suggestions would be great though. Thanks Dave Return to table of contents
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