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Contents:
  Dr. Cone Repsonds to -yeast stored-William Frazier ("Rob Moline")
  Dr. Cone Responds to -- pitching mixed cultures- Jeff Renner ("Rob Moline")
  Dr. Cone Responds to- Sven Pfitt-Mutations ("Rob Moline")
  I just had to post this... ;-) (John Palmer)
  Dr. Cone, 2003 - wort oxygenation (Bob Devine)
  Dave Logsdon Responds-- Foul Smell--Gump Comment- ("Rob Moline")
  RE: Yeast Stirring (John Schnupp)
  Dr.Cone 2003 (Jurriaan and Jann)
  Re: Double the recipe? (DHinrichs)
  Thanks (Robert Sandefer)
  Exploding CO2 tanks, really? (Calvin Perilloux)
  Re: Dr. Cone, 2003 - Killer Strains (Jeff Renner)
  Beer in NorCal/Sonoma ("Stefan Berggren")
  Dr. Cone ("Mold Testing and Solutions")
  Aerobic yeast propagation (FLJohnson)
  mash temperature too low ("Ronnie Anderson")
  Aerobic yeast propagation (FLJohnson)
  =?iso-8859-1?Q?Re:_Double_the_recipe=3F?= ("=?iso-8859-1?Q?Larry_Bristol?=")
  Re: Two-gauge regulator progress report (Kevin Wagner)
  Dr. Clayton Cone ("Harlan Nilsen")
  More Potato Beer (MOREY Dan)
  Re: Yeast Stirring (Demonick)
  Beer and Massive brain anurism. ("Chad Stevens")
  hemacytometer (orourke mike)
  Where to drink in Denver ("William Graham")
  Dr. Cone/ Tobias Fischborn Responds - Fredrik-Part 1 ("Rob Moline")


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* * * * * * * *    COMING  TO THE HBD!    * * * * * * * *
*          Dr. Clayton Cone Fortnight of Yeast          *
*      8/11/03 - 8/22/03 Yeast Questions Answered       *
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Date: Tue, 12 Aug 2003 23:40:57 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dr. Cone Repsonds to -yeast stored-William Frazier

			Dr. Cone Repsonds to -yeast stored-William Frazier

Dr. Cone - I've purchased a 500 gram quantity of BM-45 wine yeast.  This is
more than I will use for winemaking this season.  Can this yeast be stored
for future use?  If so, what would be the best conditions?  Thanks.
Bill Frazier


Bill Frazier,
Active Dry Yeast, at <5% moisture, is originally packaged in an oxygen free
atmosphere either via nitrogen flush or vacuum. Under these conditions they
will loose about 20% activity / year when stored at 20C.(68F) and about 5%
activity / year when stored at 4C.(40F). It is the presence of Oxygen and
the pick up of small amounts of moisture that causes the yeast to
deteriorate at a faster rate, once the package has been opened. If you can
vacuum pack (kitchen vacuum package equipment)or store in an air tight
container and refrigerate you may retain a substantial amount of the
activity. It would be wise to increase the inoculum 50% to be on the safe
side. It is always a gamble, depending on how much moisture the cells have
picked up each time you open and close the package and return to the
refrigerator.

Do not store in freezer.  Freezing is deadly to some strains of yeast.
Clayton Cone
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Date: Tue, 12 Aug 2003 23:44:58 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dr. Cone Responds to -- pitching mixed cultures- Jeff Renner

		Dr. Cone Responds to -- pitching mixed cultures- Jeff Renner

Dr Cone
According to beer writer Michael Jackson, the Belgian ale Duvel is
fermented with two yeasts, both originally isolated by De Clerck from
10-20 strains in McEwan's Scotch ale between the wars.  See
http://www.beerhunter.com/documents/19133-000020.html.
Jackson writes "both [yeasts] are used in primary fermentation. The
brew is divided into two separate batches, one for each yeast.  These
two batches are not of equal sizes."  The separate batches are
filtered and blended after secondary, and one of the strains
reintroduced for bottling.
Why do you think this is done, rather than simply pitching them both
into the same wort?
Assuming that there is no K (killer) factor involved (since they both
coexisted in the original McEwan's), how do you think the results
would differ if the yeasts were both pitched into one wort in the
same proportion as the sizes of the two batches at Duvel?
I'd appreciate any further thoughts you might have regarding mixed
cultures of yeasts in traditional and/or historic ales.
Thanks.
Jeff Renner


Jeff Renner,
Each strain has its own growth rate and nutrient requirement and can be
controlled better when fermented separately. When fermented together, they
may not remain 50/50 in the fermentation. One strain can easily out grow and
dominate the other throwing the desired balance of flavor and aroma off
balance.

In the wine industry, especially Champagne, it is not uncommon to ferment
three or more strains separately then blend different preportions of each to
achieve a desired mouthfeel, flavor and aroma profile.

Clayton Cone


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Date: Tue, 12 Aug 2003 23:48:32 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dr. Cone Responds to- Sven Pfitt-Mutations

			Dr. Cone Responds to- Sven Pfitt-Mutations


From: "Sven Pfitt" <the_gimp98 at hotmail.com>
Subject: Dr. Cone, 2003

I have read repeatedly that yeast will mutate after several reuses in the
homebrew environment.
If the yeast mutate at this high of a rate, how do breweries maintain
consistent yeast characteristics, and how are pure cultures maintained
without mutations?
If yeast mutate at such a rapid rate, how are yeast characteristics
maintained over the period of many years as we have seen.
It seems to me that the culprit is not mutation, but more likely
contamination.
Thank you.
Respectfully,
Steven Parfitt


Steven Parfitt,
Mutation does occur. Sometimes naturally and sometimes from abuse such as
excessive or abusive acid wash.   There is no real handle on how much of a
problem it is.  Sometimes it takes sophisticated equipment to detect the
mutation plus a DNA fingerprint on the original strain. Sometimes mutation
occurs on a portion of the gene that does not effect the beer making ability
of the yeast and go undetected because it does not effect the beer.

The big commercial breweries minimize the mutation problem by repitching
only 3 to 5 times (this minimizes infection problems also). They also draw
from a master source or culture on an infrequent bases (yearly?) and prepare
enough slants or tubes from that source to last an extended production
period. They frequently DNA fingerprint inoculums to be certain that no
mutation has occurred.

You are right.  Infection is much more of a problem.

Clayton Cone
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Date: Tue, 12 Aug 2003 22:00:43 -0700
From: John Palmer <jjpalmer at altrionet.com>
Subject: I just had to post this... ;-)

I have blanked the name to protect the quester's right to privacy, but 
this was so off the wall I had to post it. Enjoy!
John

On Saturday, August 9, 2003, at 05:34 PM, (deleted) wrote:

> Hello, John,
> My name is (deleted).  I live in L.A..  I
> came across your name in my internet search
> for a live brewer's yeast supplement.  I wonder if
> you know from whom I might purchase bulk
> quantities of unheated brewer's yeast?
> Thank you for your time.
> Wishing well,
> (deleted)

Hi (deleted),
Correct me if I'm wrong, but I get the feeling you are looking for a 
(human) dietary supplement?? If that is the case, then the answer is 
no, because while I do know of yeast manufacturers (ex. White Labs of 
San Diego) that sort of brewing yeast would not be cheap.
However...if you are really interested in ingesting live brewers yeast, 
then you could go to one of the several microbreweries around LA and 
request a yeast sample. (Tell them you are a homebrewer) You will 
probably have to come back at some point during the week with a 
tupperware container, but they could easily give you a quart of the 
stuff.
And, I have to mention that if you really intend on ingestion, that 
live brewing yeast is Laxative City!
Well, good luck,
John

On Tuesday, August 12, 2003, at 09:38 PM, (deleted) wrote:

Mr. Palmer,
YOU are so cool!.
Thank you very much for the information.
Funnily enough, Laxative City is just where I
need to be.
All the warmest,
(deleted)


John Palmer
john at howtobrew.com
www.realbeer.com/jjpalmer
www.howtobrew.com - the free online book of homebrewing



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Date: Tue, 12 Aug 2003 23:01:44 -0600
From: Bob Devine <bob.devine at worldnet.att.net>
Subject: Dr. Cone, 2003 - wort oxygenation

Dr. Cone, thanks for the expert assistance!

Question:
Some British brewers "drop" their fermenting wort
up to a day after adding yeast.  How effective is this
for adding oxygen?  And how late can wort be oxygenated?

Bob Devine
Simmering with yet another day over 100F in Utah...


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Date: Wed, 13 Aug 2003 01:19:16 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dave Logsdon Responds-- Foul Smell--Gump Comment-

			Dave Logsdon Responds-- Foul Smell--Gump Comment-

     Folks,
     As this question contains a reference to 'pitchable tubes,' and as that
has,  at  least in my mind, become synonymous with Wyeast....(WhiteLabs
describes a product as 'pitchable vials', so it could possibly be either) I
initially rejected this question....
     Consequently, I have asked Dave Logsdon of Wyeast to handle this.....
He has graciously, and at short notice stepped up...
     Thank you, Sir!
     Trusting you understand...and approve....
Gump


Dr. Cone,
   Over the past few years, I have practiced a crude form of yeast ranching.
After stepping up a smack-pack (1/3 cup DME in one pint of water, boiled
10-15 minutes) in preparation for brewing, I would innoculate a second flask
and allow it to grow to krausen and then place it in the refrigerator for
the next brewing session.  Sometimes, this brewing session would occur
months later.  Essentially, the yeast was stored under refrigerated beer.
Prior to brewing, I decant the supernatant and ptich the slurry into a
starter. Sometimes it takes 2 steps before a good karusen.  I would repeat
the process several times with the same culture, storing successuve cultures
and growing them up as needed with no detectable adverse effects.
   Recently after reading about the benefits of oxygenation/airation, I
bought
a stir plate, an aquarium pump, and an in line HEPA filter (used for IV
infusions). Additionally, I began adding 1 TSP of a "yeast nutrient" which I
interpret to be yeast hulls (yellow granular appearnce) to my cup of starter
solution during the boil.  I then fed the sanitized air line from the
aquarium pump through the HEPA filter and into the hole in the rubber
stoppered flask and stirred the culture at a moderate rate using filtered
room air for airation.
   On two occasions, once after pitching yeast sediment from one of my
refrigerator cultures and once after pitching one of the new pitchable yeast
tubes, I noted a very foul smell, much like burning plastic wire insulation
or burnt rubber.  The culture from the refrigerator made acceptable beer, no
adverse tastes but a tremendous amount of yeast sediment (I believe it was a
California ale yeast I used for a wheat beer so it was difficult to evaluate
whether the haze was due to poor floculation from a wild yeast infection).
The culture from the pitchable tube (kolsch) made two horrible batches, one
alt and and one kolsch.  In all fairness, I have never attempted these
styles before and now understand that this yeast needs to be cold
conditioned despite being called an ale yeast.  Both batches just wouldn't
clear and never developed a clean taste.
   This weekend, I stepped up another pitchable yeast tube, a Bavarian Wheat
for a hefeweizen.  I used only 1/4 TSP of the yellow yeast nutrient and
added 1/4 TSP of "yeast energizer".  I stirred for 48 hours without using
the aquarium pump.  Instead, I inserted the HEPPA filter directly into the
stopper to filter incoming ambient room air.  I detected the same foul
smell, but it was very faint.
   Is this smell due to autolized yeast?  Is it due to one of the yeast
nutrients?  How about an infection from the aquarium pump?  Am I stirring
too long and exhausting the media and nutrients causing yeast autolosys?
   Thanks in advance for your time.
Todd in Idaho




Todd in Idaho,
A couple of things you indicate follow a pattern to some extent. One key to
the questions, is the aroma that was noted to varying degrees from three
different sources. The burnt rubber aroma which appears to be a common
thread from 3 different yeast strains may be an indication. This aroma is
often associated with what some describe as 'phenolic'. This is somewhat a
catch all for a number of compounds usually associated with wheat beer
yeast, many Belgian yeast strains and wild yeast. The compounds can vary in
strength and character depending on the strain itself or how it is handled.
This would include temperatures and, aeration levels.
Some of these yeast have relatively high levels of phenylethylene, a plastic
resinous like odor, like the synthesized compound known as styrene.

Since ale yeast and kolsch yeast typically do not have measurable amounts of
phenylethylene, or 4-vinyl guaiacol, which is another common wheat beer
associated compound, it may be likely that it was introduced by another
yeast strain or wild yeast. Even in the Bavarian Wheat beer strain you noted
"the same foul smell", which typical will have detectable levels of the
above compounds.
This could be from the wheat beer strain itself, another organism, or a
combination.

Whether from a known wheat beer yeast strain or a wild yeast, the relative
levels of these compounds vary and can be perceived quite differently. I
find phenolic compounds from wild yeast and bacteria to have a much
different (undesirable profile)  as compared to German style wheat beer
strains and many Belgian yeast strains.

Regarding other possible sources you inquired about, autolysis typically can
be better described as sulphery, and dirty diaper. I have not seen where
yeast nutrients contribute the type of odor you describe either.

If you place the yeast directly from the package into fully boilded cooled
wort do you get the same foul smell?

Cheers!
David Logsdon
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Date: Tue, 12 Aug 2003 23:32:05 -0700 (PDT)
From: John Schnupp <johnschnupp at yahoo.com>
Subject: RE: Yeast Stirring

Ron give some ideas about building a stirrer:
>Definitely worth having one, but most are somewhat expensive.  You can
>build one fairly easily with a small motor with a bar magnet clamped
>to a spinner of some kind.  You could use a small brass gear as the
>spindle, clamp the magnet to it, and mount onto the motor shaft.

He is correct.  If you are a tinkerer and handy with tools you can put
something together pretty quickly.  I haven't brewed over a year now so mine is
gathering dust.  I used it regularly and found that I had more yeast growth
than without.  I also aerate with HEPA filtered air.  I don't even bother to
bubble it thru the wort as Jeff does.  I think there is more than enough mixing
if the stir speed is high enough to create a slight vortex in the liquid.

Be forewarned, I'm not a web page designer so these pages are not all fancy,
mostly text and links to photos.

Check out my stirrer page:
http://www.home.earthlink.net/~johnschnupp/stirrer/stirrer.htm
I give information about how a stirrer can be built using a DC motor, magnet
and a variable power supply.

And the starter page:
http://www.home.earthlink.net/~johnschnupp/starter/starter.htm
Information about how I use the stirrer to make my starters.

These pages DO NOT contain step by step instructions.  They provide general
information.  A lot of the specifics about building a stirrer depend upon the
materials you start with.  Also, my starter procedure might not be what someone
else does but it is what has a proved track record of working for me.


=====
John Schnupp, N3CNL
??? Hombrewery
[560.2, 68.6] Rennerian
Georgia, VT
95 XLH 1200, Bumblebee



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Date: Thu, 07 Aug 2003 20:19:24 +1000
From: Jurriaan and Jann <jannjurriaan at iprimus.com.au>
Subject: Dr.Cone 2003

Dear Dr.Cone,

At present I oxygenate my wort inline during cooling with pure (?) O2 as
I assume it to be as close to sterile as possible in a homebrew
situation and hence more practical than working with an aeration stone
and aquarium pump after cooling to pitching temp. Although I have not
experienced any problems with fermentation, I wondered what your views
on it would be regarding yeast health etc.

Thank you for devoting some of your valuable time to answer questions on
the HBD.

Jurriaan Boekamp
Hobart,
Australia




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Date: Wed, 13 Aug 2003 08:28:46 -0500
From: DHinrichs at Quannon.com
Subject: Re: Double the recipe?

"Mike Eyre" <meyre at sbcglobal.net>
Subject: Double the recipe?

>I've just recently scaled up to 10 gal. batches from 5 gal. batches.. I've
heard that, on >a large scale, you can't scale up on a linear rate.. (I.e.
going from 5 gal at home to 14 >bbl at a pub) But does that count for a
small scale HB thing like this, 5 to 10 gal steps? >Most recipes I run
across in books and online are for 5 gal, but now I want 10.. Nit->
>picking, or no?

I find on my system the efficency goes up 5-10% YMMV.

Dave, Minnetonka mn


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Date: Wed, 13 Aug 2003 09:35:39 -0400
From: Robert Sandefer <melamor at vzavenue.net>
Subject: Thanks

I'd like to thank those who responded to my All-grain Problem.

I have since brewed a second all-grain batch and hit my target mash 
temperature...of course the mash stuck <sigh> but that was problem the 5 
lbs of rye malt.

Thanks again.

Sante

Robert Sandefer
Arlington, VA



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Date: Wed, 13 Aug 2003 06:36:01 -0700 (PDT)
From: Calvin Perilloux <calvinperilloux at yahoo.com>
Subject: Exploding CO2 tanks, really?

>From previous HBD: 
> Calvin Perilloux asks why compressed gas tanks are dangerous 
> and should be chained or anchored... 

Well, no, to be perfectly pedantic, I already knew that tanks 
ought to be anchored -- I was asking why aluminum tanks 
*in particular* are more dangerous.

> Aluminum is particularly susceptible because, relative to steel, 
> it is quite brittle. -Kevin 

Really?  I have been under the impression that aluminum is 
significantly WEAKER than steel.  But more brittle?  These are
different properties.  Can one of the metallurgists chime in?

I also suspect that aluminum tanks are engineered such that they'd
not split and explode if they fell over.  Look at the smash marks 
on the side of (some of) those tanks, and you know they've had 
some very serious abuse.  Sideways smacking on the regulator would
likely demolish the more delicate regulator rather than twist apart 
the seriously-heavily-engineered top of the tank.

The main danger from falling over is probably:
(1) Falling on your foot, 
 or worse...,
(2) If the gas is on, liquid CO2 getting into the regulator and
      exploding that

But not the tank itself exploding.  Of that, I am most highly
doubtful.

Calvin Perilloux
Middletown, Maryland, USA




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Date: Wed, 13 Aug 2003 09:34:17 -0400
From: Jeff Renner <jeffrenner at comcast.net>
Subject: Re: Dr. Cone, 2003 - Killer Strains

Al K <brewinfo at xnet.com> writes from Homer Glen, IL

>Dr. Cone--
>Are there "killer strains" of beer yeast as there are in wine yeasts?

I can answer that, although not as authoritatively as Dr Cone, so I 
hope he will answer too.  The Burton Bridge Brewery in UK uses such a 
yeast according to 
http://www.midlandspubs.co.uk/burtonbridge/brewery.htm :

"The yeast was selected from the National Yeast collection catalogue 
 ... . By chance, the final selection also had a wild yeast killer 
factor"

I had thought that Rogues's Pacman yeast also had this, but a google 
search doesn't support that.

Jeff
- -- 
Jeff Renner in Ann Arbor, Michigan USA, JeffRenner at comcast.net
"One never knows, do one?"  Fats Waller, American Musician, 1904-1943


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Date: Wed, 13 Aug 2003 08:39:17 -0500
From: "Stefan Berggren" <yeastfarmer at hotmail.com>
Subject: Beer in NorCal/Sonoma

I will be traveling in Sonoma and the surrounding areas
September 13-21st and would like to get some advice
on where a beer minded individual should go?  I plan on
taking a trip to Bear Republic, but what are some of the
other breweries, brew-pubs and tap-friendly establishments
should I visit?

Stefan Berggren
Madison, WI
home of the Madison Homebrewers and Tasters Guild



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Date: Wed, 13 Aug 2003 10:08:18 -0400
From: "Mold Testing and Solutions" <mrzar at ic.net>
Subject: Dr. Cone

Thank you Dr. Cone for sharing your knowledge.

If I want to "grow" yeast fast what would be your suggestions.

I have read if you keep a constant temp, O2, limit glucose to >.4% with
stirring, yeast will stay in the resportory (growth) state and grow rapidly.
I have found limited info on the process.

What would be the doubling rate if good constants were kept?

Thank you ------- bobz



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Date: Wed, 13 Aug 2003 10:15:10 -0400
From: FLJohnson at portbridge.com
Subject: Aerobic yeast propagation

There have been a few posts recently regarding the question of whether stirring 
a yeast starter will improve yield. I doubt that simply stirring the culture 
will have a significant effect on the number of yeast cells you will produce, 
keeping all other variables the same. What one wishes to do is to keep the 
yeast metabolizing the sugar into biomass and CO2 rather than alcohol and CO2. 
To achieve this, one must maintain LOW sugar concentrations in the medium and 
provide oxygen. This will allow the yeast to respire rather than ferment. If 
the glucose concentration in the medium rises above 0.4% (approximately), the 
yeast will ferment the sugar, no matter how much oxygen and stirring you 
provide. See my post to the HBD from a few years back below.

In regard to the following post, the YeastLink web site is long gone.

Fred L Johnson
Apex, North Carolina, USA

- --
>I have been interested in establishing an aerobic yeast propogation system
>for my starters.  Such a system putatively has the advantage of producing
>large amounts of yeast in minimal volumes in minimal time.  Below is an
>excerpt from the YeastLink website in which the method and commercial
>equipment for this process is described.

> Glucose levels in a all-malt wort are in the approximate range of 1% - 
1.5
> %. Brewer's yeast has a metabolic effect where the yeast will respond to
> glucose levels above 0.4% with or without the presence of oxygen by
> metabolizing the sugar through fermentation rather than respiration.
> If the yeast propagation is aerated and the culture is fed incrementally
> with sterile wort at a rate that the yeast metabolizes the glucose to 
keep
> the level of this sugar in the propagation below 0.4%, the yeast will 
stay
> in a respiratory or growth state. A similar process is utilized in the
> production of baker's yeast although molasses is utilized instead of
> brewer's wort. Under these circumstances, far more energy is available 
to
> the yeast cell than under fermentative conditions and far more yeast is
> produced while less alcohol is produced. The yeast produced from this
> method are in highest growth phase(log phase) and can be pitched at a
> dilution rate of 1:100 or higher. The volume of the propagation medium 
is
> 1% or less of the batch total.



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Date: Wed, 13 Aug 2003 10:15:16 -0400 (EDT)
From: "Ronnie Anderson" <lerxst at webmages.com>
Subject: mash temperature too low

I bought a new digital thermometer the other day and decided to use it
during my 10 gallon brew session last night (hefe-weizen). A buddy of mine
gave me a mercury calibration thermometer, so I checked the digital one
against it at 3 different times while heating my strike water, and it was
always within 1 degree.

 - Heated strike water to 172
 - Mixed grain and water and had digital therm. probe in while stirring
 - Temp stayed steady in the 160s, so I dumped in some cold water
 - Mash temp steady at 153 according to digital therm.

After about 45 minutes I noticed that the digital therm. said it was 107
in the brew room, and the calibration thermometer said it was in the high
80s?? Took lid off and checked mash with calibration therm...135!?!?
Checked the temp with my old standby therm...133!

A quick iodine test said there was still some starch left, so I dumped in
some boiling water to get the temp up to 152 and let it sit for another 45
minutes or so before sparging.

The sparge and boil went well, but there was an extraordinary amount of
break material floating around. I actually hit my target gravity
(according to my new hydrometer, that is).

Anyone have any idea as to whether this beer will turn out ok??

TIA!
Ronnie


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Date: Wed, 13 Aug 2003 10:26:42 -0400
From: FLJohnson at portbridge.com
Subject: Aerobic yeast propagation

Oops. I forgot to include in my last post the following table showing the 
benefits on yeast production of aeration versus aeration pplus continuous 
infusion of wort into the culture to maintain low glucose concentrations.

YIELDS OF YEAST AND ETHANOL
                                         Mass (kg)
Medium   Conditions                  Yeast     Ethanol
Wort     Unaerated                    2.7      17.5
Wort     Aerated                      8.6      10.5
Wort     Aerated-Incremental Feed    23         0.7
Molasses Aerated-Incremental Feed    50         0

*from Malting and Brewing Science

Fred L Johnson
Apex, North Caroina
USA



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Date: Wed, 13 Aug 2003 10:34:16 -0500 (CDT)
From: "=?iso-8859-1?Q?Larry_Bristol?=" <Larry at DoubleLuck.com>
Subject: =?iso-8859-1?Q?Re:_Double_the_recipe=3F?=

On Tue, 12 Aug 2003 13:46:26 -0400, "Mike Eyre" <meyre at sbcglobal.net> queried:
> I've just recently scaled up to 10 gal. batches from 5 gal. batches..
> I've heard that, on a large scale, you can't scale up on a linear
> rate.. (I.e. going from 5 gal at home to 14 bbl at a pub) But does that
> count for a small scale HB thing like this, 5 to 10 gal steps? Most
> recipes I run across in books and online are for 5 gal, but now I want
> 10..
> Nit-picking, or no?

I did the same thing about 2 years ago.  My answer is "double the recipe",
especially if all other other factors remain the same (proportionally).

I think the key factor will be boil volume.  I went from a "full volume"
boil (meaning 6 gallons from the mash tun boiled 90 minutes) to a "full
volume" boil (meaning 12 gallons from the mash tun boiled 90 minutes).  With
this kind of "change", your recipes should scale up linearly.

That being said, I have to admit that I was forced to make some recipe
adjustments.  I attribute these adjustments, however, to all of the other
changes that were made simultaneously, such as a new water source and all
new equipment.  The key adjustment involved a noticable increase in hop
utilization, requiring me to reduce the amount of hops used.  This might be
explained by the increase in the wort wolume, but I find it hard to
understand why more alpha acid would get extracted in 12 gallons than in 6
when the gravity is identical in both.

- -- 
Larry Bristol
Bellville, TX
http://www.doubleluck.com




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Date: Wed, 13 Aug 2003 08:01:38 -0700
From: Kevin Wagner <kevin.wagner at watchmark.com>
Subject: Re: Two-gauge regulator progress report

Sven Pfitt dispels Kevin's rumor that valve heads are easily knocked
off...

It is likely you are absolutely correct, though, every welder I've ever
worked with has been superstitious about it. While I've never seen a
valve head knocked off, I have seen a badly damaged regulator - which
should be encouragement enough.

 -Kevin


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Date: Wed, 13 Aug 2003 11:20:56 -0500
From: "Harlan Nilsen" <ramnrah at nebi.com>
Subject: Dr. Clayton Cone

Dr. Cone,

I am planning on brewing a barley wine as soon as the weather cools off
enough so I can maintain a fermentation temp of 65-70 deg. F.  It will have
an OG of approximately 1.110.  I have purchased 3 paks of Nottingham yeast
(11 gm per pak) and am wondering if this should be enough yeast for 5
gallons.  I have been told that it may be too much yeast but I want enough
to promote a good healthy ferment.  I will aerate the wort well with pure O2
and add any fermentation aids that you may suggest.

Thank you for sharing your expertise.

Harlan Nilsen





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Date: Wed, 13 Aug 2003 11:15:31 -0500
From: MOREY Dan <dan.morey at cnh.com>
Subject: More Potato Beer

Jeff writes:

>I tasted a potato beer made by Point Brewery a few years ago for a potato
festival in 
>Wisconsin. Tasted a bit potatoey and earthy. I wouldn't bother except as a
project.

I haven't had Point's potato beer so I cannot comment to it taste.  However,
if I used the same logic, I would have never attempted a Pilsner after too
many years of Miller Lite, a fine Pilsner so they (Miller) say.  My
experience has been that potatoes do not contribute an earthy flavor.
Perhaps this is due to the fact that I peal and slice the potatoes.  The
flavor is clean or neutral.  What I have found, which surprised me, is it
added a silkiness or creaminess to the body.  Perhaps the starch structure
is more complex and the resulting sugar are less fermentable.  

For some reason there is a bias against potato beers.  My neighbor laughed
at me until he tried my "Mashed" Potato Ale.  To this day, he tells me that
out of all the beers I made, the potato beer is his favorite.

"Mashed" Potato (5 gallons)
OG	1.039		FG	1.009		Est. IBU 32		Est.
SRM 6

6.50 lb 2-row
0.25 lb wheat malt
0.50 lb crystal 10L
0.50 lb special roast
3.00 lb red potatoes
1.00 oz Perle (60 minutes)
0.50 oz Tettnang (10 minutes)
1056 American Ale

1. Dough-in with 1.1 gallons of cold tap water.
2. Boil potatoes with 0.92 gallons of water.  Add potatoes and boiling water
to bring mash up to 120F.  Hold for 30 minutes.
3. Add 0.71 gallons boiling water to raise mash to 140F.  Hold for 30
minutes.
4. Add 0.86 gallons boiling water to raise mash to 155F.  Hold for 60
minutes.
5. Mash out at 170F

A couple years later, I brewed Melting Pot Lager.  When I shared it with my
fellow brewers in BABBLE, their comments were all very positive.  Several
asked that I invite them over to brew the next time I made potato beer.

Melting Pot Lager (5 gallons)
OG	1.057		FG	1.019		Est. IBU 22		Est.
SRM 3

7.00 lb 2-row
0.50 lb wheat malt
1.00 lb rolled oats
3.00 lb red potatoes
1.00 lb wild flower honey (add at end of boil)
0.70 oz Perle (60 minutes)
0.50 oz Cascade (30 minutes)
0.30 oz Styrian golding (5 minutes)
Bavarian lager yeast

1. Dough-in with 1.03 gallons cold tap water.
2. Boil potatoes with 0.61 gallons of water.  Add potatoes and boiling water
to bring mash up to 120F.  Hold for 30 minutes.
3. Add 0.80 gallons boiling water to raise mash to 140F.  Hold for 30
minutes.
4. Add 1.10 gallons boiling water to raise mash to 155F.  Hold for 60
minutes.
5. Mash out at 170F

The last batch, Yukon Gold, was a wonderful CAP.  At competition it only
scored 29 out of 50, but this was due to low carbonation and low
bittereness.  I disagree with the judges comment concerning bitterness.
Jeff's CAP, which is excellent BTW, to me has a full/rich hop flavor.  It is
not just bitterness.  To me it is the hop flavor that is key to a good
Pilsner.  In my previous post I wasn't trying to knock corn, I wish I had as
good of results with corn or maize as Jeff and others do.

Yukon Gold (10 gallons)
OG	1.051		FG	1.018		Est. IBU 28		Est.
SRM 4

14.00 lb Belgian Pilsner
 1.00 lb crystal 10L
10.00 lb Yukon gold potatoes
 1.20 oz Centennial (60 minutes)
 0.70 oz Santium (17 minutes)
 1.30 oz Saaz (2 minutes)
Wyeast # 2272 N. American lager

1. Dough-in with 1.90 gallons cold tap water.
2. Boil potatoes with 4.08 gallons of water.  Add potatoes and boiling water
to bring mash up to 152F.  Hold for 70 minutes.
3.  Mash out at 170F


Before you decide potato beer is not for you, give it a try.  It is easy, no
cereal mash required.  You might just like it.

Keep on brewin'

Dan Morey
Club B.A.B.B.L.E.  http://hbd.org/babble
[213.1, 271.5] mi





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Date: Wed, 13 Aug 2003 10:44:59 -0700
From: Demonick <demonick at zgi.com>
Subject: Re: Yeast Stirring

I do it too, and have been for a few years.  There are yeast starter pages,
both aerated and anaerobic on my webpage, and some glassware tips. 

http://www.primetab/com/general.html

Aerated starters ferment very quickly, and I you may never notice any signs
of active fermentation.  The best indicator is the color of the solution.  
The initial wort starts out dark, but fairly clear, like any wort.  After
fermentation it resembles chocolate milk.

Domenick Venezia
Venezia & Company, LLC
Maker of PrimeTab
(206) 782-1152  phone
(206) 782-6766  fax
Seattle, WA
demonick at zgi dot com
http://www.primetab.com



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Date: Wed, 13 Aug 2003 12:02:52 -0700
From: "Chad Stevens" <zuvaruvi at cox.net>
Subject: Beer and Massive brain anurism.

One and all,

My Father-in-law had a massive brain aneurysm Friday evening (it's been a
long week) virtually displacing one hemisphere with blood.  His 75th
birthday is Friday and he has been a chronic consumer of
fat/cholesterol/salt with a bp of 240/200 or better most of the time.  He
had about five Tecate beers on Tuesday, three days before the aneurysm.

Alcohol in moderation is a vaso-dilator reducing blood pressure.  It is my
understanding that in heavy doses alcohol can become a vaso-constrictor.
His family is blaming the aneurysm on his binge three days before rather
than accepting the fact that diet/lifestyle is the chief culprit (and my
concern is that they will fall to much the same demise if they don't change
their eating habits).

So my question is, could the alcohol have played some role in his having an
aneurysm when chronic high fat/cholesterol/salt intake is the obvious
culprit?

Thanks,

Chad Stevens
San Diego

P.S. Is anyone going to introduce Dr. Cone to the gyno thread?  (snicker,
guffaw)



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Date: Wed, 13 Aug 2003 12:53:07 -0700 (PDT)
From: orourke mike <dert12345 at yahoo.com>
Subject: hemacytometer

Anyone have a make/model of a suitable hemacytometer
for yeast cell counts?  I found this one
https://www1.fishersci.com/Couponcid=1333&gid=139669&details=Y
and am wondering if it will work.



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Date: Wed, 13 Aug 2003 16:47:05 -0600
From: "William Graham" <billg at compasscom.com>
Subject: Where to drink in Denver

Alex Hazlett <alexdhaze at yahoo.com> wants to know where to drink in Denver -

	Just off the top of my head, start in LoDo and go to the Falling Rock. 69
beers on tap and "no crap on tap". Wonderful selection and Chris ( the
co-owner ) can talk your ears off about beer. The staff are usually quite
knowledgable and friendly. Then, stroll soutwest 1.5 blocks and northwest 2
blocks to the Wynkoop. Not a beer wonderland but many good beers available,
and many accessible to our less-enlightened friends. I've also enjoyed the
food there. If you wish to stay in Lodo, you can go to Broadway Brewing,
Rock Bottom, Breckenridge, and the Sandlot BP at Coors field. There are a
few others, I'm sure, but it's been awhile.

	Go west to Golden. Go into Coors and take the "short" tour. Just ask a
guide. ( The short tour means going directly to the tasting room ). The
absolutely fresh Coors is worth the 20 minute diversion. Then find Golden
City Brewing. A fine little brewpub literally in a garage in one of the
older neighborhoods in Golden. You can get an sandwich and a bag of chips on
a paper plate and eat in the back yard along with your fine and fresh beer.
I just like that small town atmosphere.

	Then go north to Boulder. Go directly to Mountain Sun just east of the
Pearl Street Mall. Just about one of the best brewpubs in Colorado, with the
emphasis on beer. Please have a 'Colorado Kind' followed by an "XXX". Please
thank me in private. If you're hungry, walk up to BJ's Pizza, where they
make good pizza and good beer.

	Frankly, I have to stop here. There are so many brewpubs in and around
Denver that I can't possibly list them all ( one hell of a problem, I tell
ya!... please keep the sympathy messages offlist, okay? Save room for the
other posters ). IMHO, these that I mentioned are at the top of the list.

Bill
	Used to live in Golden, now living in Elizabeth, 52.3 miles from Falling
Rock.




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Date: Wed, 13 Aug 2003 22:47:02 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dr. Cone/ Tobias Fischborn Responds - Fredrik-Part 1

			Dr. Cone/ Tobias Fischborn Responds - Fredrik-Part 1
Folks,
	We are fortunate to be joined by Dr. Tobias Fischborn of Lallemand, a
colleague of Dr. Cone. Clayton said he may be asking for help from such
luminaries in the field as Tobias, as he says "No one can know it all!" (I
will resist the urge to phone Dave Burley to tell him this!-Gump-- ;-)  )

Fredrik,
   You have taken on a huge task which is beyond what I can help you with in
a
brief session.  The variables are mind boggling in a batch process. The
media that the yeast finds itself is dynamic. It is changing from moment to
moment: The stress of the osmotic effect is going down as the sugar is
converted to alcohol.  At the same time the stress of the alcohol is
increasing. The number of yeast cells are increasing during the first 1/3 to
1/2 of the fermentation.  The individual yeast cells produces 20 - 30 times
as much alcohol while it is growing than it does when it reaches the
stationary phase. Available nutrients change as the yeast grows. Temperature
can change if good controls are not in place. pH and CO2 levels change.  In
a continuous, steady state process the variables are minimized yet are still
many. Each variable effects the rate of fermentation and the resulting CO2
production.  Many researchers have worked out good models on separate
variables and some variables in combination.  I would suggest that you find
a good technical library and search through both brewing and wine technical
journals.
   Since you are interested in transport systems, enzymes and metabolic
pathways, I will suggest two excellent text books:

"Brewing Yeast Fermentation Performance" 2nd. edition, edited by Katherine
Smart (last name very descriptive) Blackwell Publishing, ISBN 0-632-06498-6.

"YEAST Physiology and Biotechnology" by Graeme Walker, Wiley Publisher, ISBN
0-471-96446-8.

   Please feel free to ask more questions. I sometimes feel that I am not on
the same wavelength as you, so I may not answer the question to your
satisfaction.
   I have asked a colleague to add something to your questions.  His
comments
are under "Tobias."
   You will find my answers under "Clayton" at each of your questions,

"Clayton" Cone

Greetings Dr.Cone!
   Since some months ago I am attempting something as stupid as a beer
fermentation simulation model and I've many questions that I would love to
have your and everybody elses opinion on. I can't choose which are most
important questions so I will just list them all. I don't expect to get
answers to all of them and I don't even know to what extent all questions
are well defined. But in any case all ideas and input on some of them from
you would be very appreciated! The background of the question is a quest to
find an algorithm that will simulate yeast and the most relevant parts in
fermentation, and as accurate as possible predict the CO2 production with
time.
   Related to yeasts sugar utilization that may be of interest for stuck
fermentations, in a wort consisting of mono, di and trisaccharides, I've
read that the simplest sugars are the first to be transported into the cell
and digested and each sugar needs a specific enzyme in order to be broken
down to monosaccharides. If the transport proteins are blocked or if for
some reason the relevant enzyme to break down the sugar is deactived the
fermentation may get stuck?
   My questions are, (sugar utiliztion)

1) what basic variables could possibly determine the synthesis and activity
of these enzymes, as well as the activity of the transport proteins?

Clayton:
STRESS. Extended period in cold storage before re-pitching. Inadequate
temperature during cold storage. Poor temperature control during
fermentation. Nitrogen starvation. Excessive repitching. Vitamin, mineral
and oxygen deficiencies. Glucose/maltose out of balance. Glucose represses
the maltase activity until the glucose is below about 0.4%.  High levels of
glucose adjunct can cause a problem special attention is given to the
fermentation.

2) What are the possible mechanism for jammng or blocking a transporter or
inhibiting an enzyme (like maltotriase) that would in turn cause a stuck
fermentation?

Clayton:
All of the replies to question 1).  If the yeast is stressed for any of the
above reasons, often times it can't quite finish the job of attacking the
last bit of sugar which happens to be Maltotriose.

3) Also, when does the synthesis of these enzymes occur (ie. maltase,
maltotriase, etc)? Does it occur upon request when a new type of sugar is
arriving, or is it synthesised during budding or maturation so it only has
to activate? Or are they always active?

Clayton:
I believe that the enzymes are produced on demand.

4) Also "how sequenced" is uptake of the sugarprofile? Is there an overlap
in the mono -> di, and di -> tri transitions, or is there possibly a tiny
delay or dip in energyproduction for that transition?

Clayton:
There is no delay between the glucose and sucrose uptake.  The Maltose
fermentation kicks in when there is <0.4% glucose.
- ---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.509 / Virus Database: 306 - Release Date: 8/12/2003



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---