HOMEBREW Digest #2791 Sat 08 August 1998
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FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
Digest Janitor: janitor@hbd.org
Many thanks to the Observer & Eccentric Newspapers of
Livonia, Michigan for sponsoring the Homebrew Digest.
URL: http://www.oeonline.com
Contents:
Yeast growth/Repitching yeast/old, thin, bald stout/plato (George_De_Piro)
Re: Crystal malt & mashing (Peter.Perez)
Force Carbonation of Cornys ("Buchanan, Robert")
pH (Paul Niebergall)
sweet gale (Al Korzonas)
Alexander's/pH (Al Korzonas)
Conical Fermentors? (Badger Roullett)
tri-pell (Badger Roullett)
keg blowoff/100IBUs/utilisation/passivation/yeast growth/IM/force-carb (Al Korzonas)
Keg -> Bar Tap: Pressure? (Badger Roullett)
Re: Enzymologists' pH optima (Fred Johnson)
Sight Glass (Badger Roullett)
Quaternary Sanitizers and TSP (Rick Theiner)
American Brewers Guild-Adv homebrew course (Mike Allred)
Iodophor, Pe^(rt), homebrew twange, celler temps (Jason Henning)
Pressure Drops and Wine ("Sandy Macmillan")
Sierra Nevada Bigfoot clone??? ("Brian Dixon")
sulfites, etc. (Dick Dunn)
Pitching -- which is better (James_E_Pearce)
Barleywine conditioning (David Sherfey)
Oak in Brewing ("Buchanan, Robert")
There will be a Sunday Digest this week...
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----------------------------------------------------------------------
Date: Wed, 5 Aug 1998 13:27:29 -0700
From: George_De_Piro at berlex.com
Subject: Yeast growth/Repitching yeast/old, thin, bald stout/plato
Hi all,
Peter talks about growing yeast, and says that pros won't start from a
smack pack, but instead purchase centrifuged cells. While some small
brewers do buy litre "slurries" from Wyeast, this is not the rule (nor
is it enough yeast to pitch even an average brewpub batch; many
brewers grow it up from that stage).
No matter how big of a batch is being brewed, it all starts with yeast
on a slant (or plate, or some similar storage medium). Small brewers
(and large) can and do grow yeast just like some of us do. It's a lot
cheaper than buying slurry, and I tend to trust my QC more than I
trust Wyeast's.
Peter then writes in response to Mort's statement about yeast growth
and rate of fermentation:
"But do you mean that we can simply pitch 7 grams of dried yeast per
gallon and forget aeration? Is yeast growth not important?
In short, yes, you can get a complete fermentation by overpitching
yeast and underaerating. Lyn Kruger, Paul Smith and I spoke a bit
about how it is possible to use aeration (or lack thereof) to control
yeast growth, and thus the final character of the beer. I think I
posted about this stuff back in Feb. She said they do this at South
African Breweries. They do NOT repitch the yeast that is treated this
way, though. Their goal is to minimize yeast growth in the fermenter.
Paul Smith was of the opinion that while you could control certain
flavors characteristics by manipulating O2 levels, it is a dangerous
method (because of the increased chance of fermentation problems). He
called this "brewing on the edge." He believes it is far easier, more
reliable, and more reproducible to control beer character through
things like fermentation temperature rather than over-pitching yeast
with no (or little) oxygenation.
--------------------------------
Fred talks about the joys of repitching yeast. I agree that it is the
best way to get your ferment off to a fast start. It is almost
essential when making high-gravity beers. There are some caveats,
though:
Yeast do not store very well. I have done cell counts on stored
slurries (stored at ~38F under unfermented wort, which they slowly
ferment). After 2 weeks half the cells absorb methylene blue (they
are dead). Repitching a culture like this can cause problems like
yeasty off-flavors and sluggish fermentations (because you are not
pitching nearly as much yeast as you thought you were).
There is also the danger of contamination. Be very sure that you like
the way the mother batch tastes before you commit another batch to the
yeast. Acid washing is not something that many homebrewers have the
equipment to do (a pH meter is essential), and it will not cure all
infections anyway. Acid washing yeast with >8% ethanol in the slurry
will result in yeast genocide.
If you consistently harvest the earliest (or latest) flocculators, you
will be selecting for very flocculent (or nonflocculent) yeast. In
time, you will have ferments that do not behave the way the original
one did. It's natural selection occurring right before your eyes,
with you in the role of Mother Nature (sounds fun!).
In summary, harvest the yeast as soon as fermentation subsides (to
ensure a viable, robust crop) and use it as soon as possible (within a
week). Chill the yeast to near freezing as quickly as possible (big
breweries use heat exchangers, we can use buckets of ice water), store
it near freezing and do NOT aerate it.
--------------------------------------
Spencer weaves a tale of woe about a stout gone bad. His oatmeal
stout was once a beautiful, vibrant, beer, with a rich body and head
to match. Sadly, it is not growing old with grace (thin and
headless).
Spencer fails to mention if the beer is bottle conditioned or
filtered, but my guess is that there is yeast present. If there is no
contaminating organism that has chewed up the proteins that are
responsible for the good head and rich body, then it is likely that
yeast autolysis is the culprit. There has been some discussion about
how Wyeast 3068 is prone to autolyze, and that proteolytic enzymes are
released when this occurs. The same thing will happen with other
yeasts, it just may take longer than with 3068.
If you know what the pH of the beer was at packaging, compare it to
the pH now. If autolysis is the culprit, the pH will be higher than
at packaging.
---------------------------------
David asks why pro brewers like to use the Plato scale when specific
gravity is so convenient. I like to think of it as Metric vs.
America. The Plato numbers have a meaning that is easy to comprehend:
it is the % of sugar in the wort (Plato based his numbers on sucrose
measurements, I think, but close enough). Specific gravity numbers
have no intuitive meaning (not to me, at least).
For some strange reason, many homebrewers don't use Plato. They are
the equivalent of the average American (who doesn't know a liter from
a kilogram). My hydrometer has both SG and Plato numbers on it, so
using either is a snap. Plato numbers make certain calculations
easier than SG (like figuring out the amount of unfermented wort to
add to a batch to get the proper degree of carbonation).
Have fun!
George De Piro (Nyack, NY)
Return to table of contents
Date: Wed, 5 Aug 1998 14:07:54 -0400
From: Peter.Perez at smed.com
Subject: Re: Crystal malt & mashing
In HBD 2779, Hans mentions:
"A couple of weeks ago, there was a discussion here about mashing
crystal malt. Stephen strongly suggested to not mash crystal
malt; it would tend to lose some of the flavor that we want from
it. He suggested adding it at the end of the mash, or even
better, to the sparge water."
I like the idea of not mashing Crystal, and instead steeping it in the
sparge water. But to me it seems like it would be better to steep it in
the wort form your 2-row (or whatever) just before adding bittering hops
and boiling. Would this be better? If not, why is steeping in the Sparge
water ideal? I am thinking that you have a better chance of losing some
color and flavor from the crystal (as it filters through the grain bed) if
you steep it in the sparge water as opposed to the pre-boil wort.
I would also like to know if Hans or Stephen meant its better not to mash
any specialty grains or just crystal?
P.S. - The recent chain on Phil's Phloater provided me with the real reason
I was getting stuck sparges. I didn't even bother looking down into my
mash tun after I had the water in it, so I never noticed that the false
bottom was floating up on the side that isn't attached to the drain.
Thanks,
Pete
Return to table of contents
Date: Wed, 5 Aug 1998 14:20:38 -0400
From: "Buchanan, Robert" <RBuchanan at ChristianaCare.org>
Subject: Force Carbonation of Cornys
I've been a bit behind so if this has been recently corrected I apologize.
In HBD #2785
Marc Battreall posted Rob Arguello's method of force-carbing a corny.
However he got the gas intake valve the wrong way. The valve should be
down. It needs to buble through the beer. The rest of the paragraph states
you can hear the gas bubble through the beer. Valve has to be down to allow
this. Continue...
Bob Buchanan
"There are TWO rules for success in Life:
Rule 1: Don't tell people everything you know."
Return to table of contents
Date: Wed, 05 Aug 1998 13:24:58 -0500
From: Paul Niebergall <pnieb at burnsmcd.com>
Subject: pH
Jeff Pharr writes:
>A question or two on the process of acidifying the sparge water:
>.....I have been trying to use gypsum additions to adjust the pH
>of the sparge water downward. But even the addition of massive amounts
>(massive being 12 teaspoons in 12 gallons of sparge water), the pH
>remains pegged above the upper limits of my pH test strips (pH 7.0).
>What is everyone else doing to bring down the pH?
First of all, you need to get some pH test trips that read above 7.0. Or
better yet purchase a hand held pH meter. I use lactic acid for acidifying
my brew water. My water supply has an extremely high pH (generally in
the neighborhood of 10.0 to 10.5 - depending on the time of the year it
is). The day before I brew, I fill a clean, converted, bbl beer keg
with about 12 gallons of carbon-filtered tap water. I then add lactic
acid until the pH drops below 7. It doesn*t take much - usually 3 to 4 mL
is sufficient. I then use this as stock water for all of my brewing
activities (mashing, sparging, make-up water, etc.). I don*t have any
idea of the strength of my lactic acid (I bought it at my local brew
supply store) and I could go into a long discussion about the negative
logarithm of the hydronium ion concentration and then calculate to the
milli-mole exactly how much acid to add. But why bother, I have a decent
pH meter, so I use it for what it is intended. Though I have never tried
it, I hear that food grade phosphoric acid will work as well.
I do not get too concerned about achieving an optimal pH range during the
mash and sparge. I figure my tap water is so alkali that it has to be
treated. So I treat it to near neutral and then proceed with my brewing.
If the water came out of tap at pH = 7, I probably wouldn*t do anything
at all.
>Should I just start buying gypsum in 50lb sacks?
>What are the problems associated with excessive gypsum usage in the
>mash?
Forget about trying to treat your water with gypsum. You have already
found out it will not work for your water. That much gypsum is can lend a
harsh flavor to your beer. It is reported to accentuates hop bitterness
also.
>What are the problems with using sparge water with a pH up around 7.5?
It*s not he pH of the sparge water going in to your lauter tun that could
be a problem, it is the pH of the runnings coming out that could be a
problem. I pH of 7.5 going in is perfectly alright. This is pretty close
to neutral and the natural acidity of the grain bed will keep the runnings
low enough. I have used lautering water as high as a pH of 9 and still
did not observe overly high pH levels (>6) in the lauter run-off. Even
when I sparge for a long time, the specific gravity of the runnings
usually drops to a point where going any further is not justified, but the
pH of the runnings is still acceptable. However, do check the pH of the
run-off on it*s was out of the lauter tun. If it rises above 6, you may
be leaching unwanted compounds (phenols from the grain husks) into your
wort that could cause an astringent taste in your finished beer.
Brew on,
Paul Niebergall
Kansa City
Return to table of contents
Date: Wed, 5 Aug 1998 13:33:18 -0500 (CDT)
From: Al Korzonas <korz at xnet.com>
Subject: sweet gale
Martin asks about sweet gale use...
In Cindy Renfrow's excellent book "A Sip Through Time" there are a
number of recipes that call for sweet gale, although in the herb
glossary in the back, she warns that it is mildly toxic (how, I don't
recall). You can also buy wormwood, incidentally, which is seriously
toxic...
I know her book is available from various stores, but you can buy
it from her directly at http://www.alcasoft.com/refrow/asip.html
(no affiliation other than being a happy customer).
Al.
Al Korzonas, Palos Hills, IL
korz at xnet.com
http://www.brewinfo.com/brewinfo/
Return to table of contents
Date: Wed, 5 Aug 1998 13:54:26 -0500 (CDT)
From: Al Korzonas <korz at xnet.com>
Subject: Alexander's/pH
I wrote:
>Alexander's is only 33 pts/lb/gal! It is less
>dense than other extracts because it is concentrated less. Subsequently,
>it is also one of the palest extracts and has less caramel flavour than
>most (which may be good or bad, depending on the style, but it's far
>easier to *add* caramel flavour than to subtract it!).
To which Peter responded:
>I don't think I assumed 36.54 pt/lb/gal for Alexander's Pale. I think I
>showed it. CCC says their extract is 80 brix. What am I missing?
Beats me... perhaps the 80 brix is for the bulk and the 33 pts/lb/gal
is for the canned. I know that the canned extract is far thinner than
most and the Zymurgy article a year or two ago on extracts showed
exactly what the pts/lb/gal were for two dozen extracts. That's where
I got the 33 from (Rolling Rock couldn't be made from Alexander's,
could it?...naaa...).
***
As for the pH change with temperature, I've never tried to measure the
change... I don't even own a pH meter... I read about it in AJ deLange's
articles in Brewing Techniques and here in HBD. Check the archives.
AJ says that pH goes down with a rise in temperature, so I believe him.
Incidentally, I suspect the actual pH change depends on your water chemistry.
Al.
Al Korzonas, Palos Hills, IL
korz at xnet.com
http://www.brewinfo.com/brewinfo/
Return to table of contents
Date: Wed, 5 Aug 1998 12:33:10 -0700
From: Badger Roullett <branderr at microsoft.com>
Subject: Conical Fermentors?
randy.pressley at SLKP.COM
Subject: Conical Fermenters
"Has anyone ever used the plastic connical fermenter sold by Afordable
Conical (http://members.aol.com/aconical/index.htm)? It's a 6.5 gallon
fermenter which looks just like the ones the pro's use except it's plastic
and little.
Looks like it would take away the hassle of the secondary transfer. "
any one know of a conical fermentor for 15+ gallons? thats cheaps? i am
looking into larger batches because i can't brew as often. (and really
quick and short... why is conicial better again?)
badger
***************************************************
Brander Roullett aka Badger
Homepage: http://www.nwlink.com/~badger
Brewing Page: http://www.nwlink.com/~badger/badgbeer.html
In the SCA: Lord Frederic Badger of Amberhaven
Return to table of contents
Date: Wed, 5 Aug 1998 12:38:03 -0700
From: Badger Roullett <branderr at microsoft.com>
Subject: tri-pell
Date: Thu, 30 Jul 1998 09:09:30 -0500 (CDT)
From: Samuel Mize <smize at mail.imagin.net>
Subject: Dan Cole's BYO discussion; speling/spellling; force carb technique
"Spelling: the style was named when a warrior had a few, then went to
practice and saw three target poles instead of one. So the correct
spelling is tri-pell. You see, the poles they use for practice are
called pells. Never mind. Hi, Badger."
I could very well be teh only one who gets that joke.....
then again, knowing how wierd brewers are, and how wierd SCA people, it
might not be just me...
I never drink before i fight, i fight, then i drink. its easier on the
head... get hit in the helm too many times, and then drink to releive the
pressure..
BANG!!
Back to brewing, and fighting, and drinking....er ...oh yeah, and wenching..
(did she hear that?!? oh no, run...)
***************************************************
Brander Roullett aka Badger
Homepage: http://www.nwlink.com/~badger
Brewing Page: http://www.nwlink.com/~badger/badgbeer.html
In the SCA: Lord Frederic Badger of Amberhaven
Return to table of contents
Date: Wed, 5 Aug 1998 15:50:34 -0500 (CDT)
From: Al Korzonas <korz at xnet.com>
Subject: keg blowoff/100IBUs/utilisation/passivation/yeast growth/IM/force-carb
Steve writes:
> When I ferment in the kegs I use a blow off method by attaching
>clear tubing to the CO2 /Gas side connector and putting the other end in
>a container filled with water and clorine bleach. I can attest to the
Three warnings:
1. If the pitched wort is hotter than room temperature, the cooling wort
and headspace can easily suck that chlorine bleach water up the blowoff
tube and into the beer.
2. Some yeasts, e.g. 34/70 (Wyeast #2124 allegedly) and Whitbread,
don't like working in fermenters that are much taller than they are
wide.
3. Having experience three explosions due to too-small blowoff tubes, I
can assure you that with or without the connector (i.e. slipping the
tube right onto the tank fitting after removing the connector with a
wrench) those pathways are just too small. Yes, I know that the tanks
are rated to 130 psi (new), but if it clogs, the beer will carbonate
and when the clog gets ejected you can lose as much as half of the batch
to foam!
***
Joe writes:
>In Nederland Colorado (quite a bit south of your route, I'm afraid), there is
>a small brewery (Wolf's Toungue) that makes a Mr. Hoppy IPA, this is the
>hoppiest beer I have ever had commercially. I am sure it is well over 100
>IBUs. (snip)
Also, Mike writes:
>Is there an
>IBU level above which differences cannot be perceived? Could an
>experienced judge discern the difference in taste between a 70 IBU beer
>and a 120?
Unless they add bitterness via isomerised hop extract, it's physically
impossible to get much over 100 IBUs. The solubility of isoalpha acids in
hot wort is only 120 mg/l and you lose a *lot* of that via break and during
fermentation. My guess is that it's difficult to *reach* 100 IBUs let alone
surpass it.
In my opinion, you can taste the difference between an actual 70 and an
actual 80 IBUs, but getting there is another story altogether!
***
Laurel writes:
>For whole hops the best utilization you can expect is about 5-8%, even
>when boiled for 60+ minutes - at least that I've ever heard of. Just as
>a rough estimate, a 30% utilization would be some four times too high:
>your real BUs would be about a quarter of the amount you calculated,
>which makes a lot more sense (about 20 BU). Just for the record, hop
>pellets yield much better (because the lupulin has been exposed prior to
>pelletizing and the pellet breaks apart more easily in the boil), at
>something like 8 - 20% utilization.
I think you're being too pessimistic... I've got test reports from Siebel
on beer that I made. It indicates that I got 27% utilisation from pellets
on a full-boil batch and 22% from a concentrated boil. My own empiracal
data indicates that I've gotten upwards of 25% utilisation from whole
hops.
***
Matt writes:
>3) "Passive surfaces can be maintained naturally when exposed to an
>oxidizing environment. Natural sources of oxygen include air, aerated
>water, and other oxidizing atmospheres. Beside naturally occuring
>passivation, chemical (nitric acid) and electro-chemical processes can
>be used to re-establish an anodic oxide film".
A long time ago, John Palmer posted that we can perform repassivation
of Stainless Steel with nitric acid. He then later recanted this,
saying he was mistaken. Now Matt says that nitric will form an oxide
layer...
Which is it?
***
Jim writes:
>According to Lyn Kruger during class and over a few glasses of Guiness the
>most
>growth you want for ales and lager, regardless of scale (5 gallons or 900
>barrels) is a ~3X. A yeast cell in ideal condition hits the fermenter with 1%
>sterols, each division reduces this by half. Yeast with 0.25% sterol are at
>the minimum level one wants ideally. The lag phase is an adaption period and
>if the yeast come from an environment of proper nutrition and good aeration
>then the adaption phase is shortened. Is autolysis rare in homebrewing?
>Without doing viability staining this is purely conjecture in my view.
I've read where the recommended growth is 5X to 10X, but this is with
lots of oxygen. I can also think of one style in which the growth is
100x or more. The question on my mind now is: "Is Jim's ability to brew
pLambics now ruined?"
***
Jim writes (quoting me):
>> How many of those instructors and brewers at Industrial breweries have
>> done side-by-side boils on all-malt worts with varying amounts of Irish
>>Moss?
>> My guess is none.
>I'll ask about what has been done in the pilot brewery. So you did all these
>experiments with the exact same lot of malt and hops and yeast strain with
>the
>exact same recipe three times each? And then by t-test you had "significant"
>results with a p-value less than 0.05? :-)
>Why should using Irish Moss effect yeast flocculation? Irish moss is for
>proteins. Unless it gets carried over into the beer.
Yes.... same malt, hops and yeast. The visual difference was stunning.
In my extract test, I made up four 1-liter "batches" in Erlenmeyer flasks
using rates equivalent to 1/4 teaspoon per 5 gallons, 1/2 teaspoon per
5 gallons and 1 teaspoon per 5 gallons. There was also one without any
IM. The 1/4 teaspoon was crystal clear in 5 days. At that time, the
no-IM was still cloudy and the yeast still in solution. The 1/2-teaspoon
and 1-teaspoon batches were even cloudier than the no-IM batch. After
two weeks, the no-IM was almost as clear as the 1/4-teaspoon batch as
was the 1/2-teaspoon batch. The 1-teaspoon batch was the cloudiest
of all.
I had wondered about the relationship between IM and yeast flocculation
back when Jeff Frane posted about it a few years ago. This experiment
really opened my eyes to it. I suspect that the effect may be that
suspended break interferes with the yeasts' ability to flocculate (i.e.
the yeast are coated with break material). DeClerck even goes so far
as to say that if you don't get a good cold break, it can interfere with
the yeasts' ability to uptake some nutrients.
***
Marc posted that he has tried Robert Arguello's Force-Carbonation
technique and it works well for him (chill beer in freezer for
4 hours, attach CO2 at 35 psi and then rock for 4 to 5 minutes).
I'm not comfortable with that method. It seems to work for Robert
and Marc, but everyone's freezer is different and everyone's beer
*starting* temperature is different. So if the beer in the keg
happened to get down to 40F in those 4 hours, 5 minutes at 35 psi
could give you more than 5 volumes of CO2!!!
I urge everyone to print out Alan's excellent tables that were
recently reposted, set the CO2 pressure to the one you need for
the actual temperature and volumes and then rock the keg until
the CO2 stops flowing. Actually, since I've personlly made the
following mistake more than once, let me suggest that you
disconnect the gas line from the keg during shaking. Sure,
that bubbling sounds cool, but what do you do when beer starts
climbing up your CO2 hose back towards the regulator?
Al.
Al Korzonas, Palos Hills, IL
korz at xnet.com
http://www.brewinfo.com/brewinfo/
Return to table of contents
Date: Wed, 5 Aug 1998 15:12:31 -0700
From: Badger Roullett <branderr at microsoft.com>
Subject: Keg -> Bar Tap: Pressure?
Greeting Lagerheads...
tis I badger, the fearless brewer...
I have discovered another gadget, and is always the case, I get it working,
but not really sure exactly what all is going on with it...
Gadget: Chrome Bar Tap directly on my keg thru the use of the Phils Phunny
Gizmo Adapter Thingie.. (I don't know what its called) its a chromed piece
of metal that fits in the back of a Bar Tap (without the shank) and screws
DIRECTLY onto a Liquid out fitting...
what this results in is a bar tap sticking right out of your keg. works
GREAT, especially if your camping, and you have a milk crate with a 5 gallon
keg, your tank in the other corner, and the whole thing covered in cloth.
One piece, can move it easily, and the parts and regulators are all shoved
in the sides..
You can pull Drafts right off the keg.. adds some class.. no more cobra
taps in the dirt..
(no association btw, just a happy happy beer drinking customer)
But My Question (I was getting to that) is this...
since there is ALMOST NO hose or travel length from the keg to the
dispensing end, is there some sort of different settings for the gas? or
something like that? should I set the pressure Lower? or higher?
thanks!
***************************************************
Brander Roullett aka Badger
Homepage: http://www.nwlink.com/~badger
Brewing Page: http://www.nwlink.com/~badger/badgbeer.html
In the SCA: Lord Frederic Badger of Amberhaven
Return to table of contents
Date: Wed, 05 Aug 1998 18:42:59 -0400
From: Fred Johnson <FLJohnson at worldnet.att.net>
Subject: Re: Enzymologists' pH optima
AJ responded with some helpful information about measuring pH at different
temperatures and about the conventions that some use. AJ also responded
to my question regarding the convention for specifying pH optima,
> With respect to Fred Jonson's question: it is my impression that enzyme
> optimum operating points are specified at their optimum operating points
> i.e. the optimum temperature is specified at the optimum pH and the
> optimum pH at the optimum temperature. I hope one of the pro's will
> comment on this.
>
but I'm not entirely sure my question was fully understood. AJ hit the
nail on the head earlier in his post (the nail I was trying to drive home)
that the relevant pH in question is the optimum pH range of the enzyme. I
reiterate my assertion that I am not interested in what anyone's standard
practices or conventions are for measuring pH EXCEPT the enzymologist who
published the data on the pH optima of the enzyme.
It is conceivable that the pH range at which an enzyme has its maximum
activity under the conditions of a lower temperature could be different
than the pH range at which that enzyme has its maximum activity at 150 F.
The real question is what is the pH range at which the enzyme has its
maximum activity at mash temperatures, AND how does the enzymologist
specify this. My guess is that the listed pH optima are at the optimal
temperature. This doesn't mean the enzymologist has to actually measure
the pH of the wort at that temperature. He could simply cool it and make
the correction as AJ has indicated. And as AJ have well pointed out, this
is something that one needs to calibrate and not make any assumptions
about if one is truly interested in measuring pH accurately.
So, do the enzymologists have this measurement under control or not? That
is, do the enzymologists consistently actually measure the pH at the
optimal temperature or do they consistently make the correction for the
difference in temperature? Or are there some not-so-careful enzymologists
out there publishing pH optima out there that are uncorrected for
temperature differences? Can I trust the published pH optima or not? If
I can, we all know how to measure pH thanks to many who have posted on
this, and there is no problem. My biggest concern is that there may not a
convention among the enzymologists for measuring the pH optimat??that the
published values have not been consistently corrected for differences
between the temperature at which the enzymatic activity was measured and
the temperature at which the pH was measured.
- --
Fred L. Johnson
Apex, North Carolina
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Date: Wed, 5 Aug 1998 15:59:47 -0700
From: Badger Roullett <branderr at microsoft.com>
Subject: Sight Glass
Can you tell i am catching up on my mail? sheesh, almost 5 posts in 1
day!?!?
any way, here is my next question...
Sight Glass.. i hear it discussed all teh time, but i don't have any idea
how it works..
From: GuyG4 at aol.com
Subject: Keg conversion and sight tube insight
"compression elbow. I installed another compression elbow of the same size
above this one, up by the handles, for a sight tube."
"If you're installing a sight valve in this fashion, make sure the top of
the
sight guage drains back into the kettle. If it does, you won't lose beer,
it
just goes back in, as the water in the tube gets air pushing it around prior
to boiling."
i get teh idea here, that he installs it at the TOP of the keg? what is the
method of getting a sight glass to work? i just managed find to trade a 5
gallon keg for a sanke, and want to make a kettle out of it..
Also, in teh construction of a 15 gallon system.. what modification are nice
to have on which pots? i have a 15 gallon GG style with a spigot at the
bottom, should i use it for Mash water (the top keg) or is it a better
boiling pot?
i know the mash/laughter tun will have a easymasher type thing or SS
screen... but what else is good to plan to have in it? temp probe? other
cool things?
badger, the brewing guy
*********************************************
Brander Roullett aka Badger
Brewing Page: http://www.nwlink.com/~badger/badgbeer.html
Badgers Brewing Bookstore: http://www.nwlink.com/~badger/brewbook.html
In the SCA:
Lord Frederic Badger of Amberhaven, Innkeeper of the Cat and Cup Inn
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Date: Wed, 05 Aug 1998 21:33:49 -0400
From: Rick Theiner <logic at skantech.com>
Subject: Quaternary Sanitizers and TSP
>From Sandy Macmillan:
> My local guy is trying to tell me that F25 sanitizing rinse by Rochester
> Midland will not harm by stainless steel kegs and is a no rinse sanitizer.
This is true.
> Anyone have any experience with this product or any advise to a non chemist.
Yes. Don't use it for brewing. Quats are essentially surfactants and
will remain on the surface after drying. The effect is pretty much the
same as washing your equipment with liquid dish soap and not rinsing
well. In my line of work (food service sanitation), we use quats a lot,
but never in a bar, brewery, or any other similar situation.
>From Anton Verhulst:
> I'm anticipating the day when TSP will be banned in the US and have bought
> what I anticipate to be a lifetime supply (10 pounds).
Don't count on it. TSP is one of the best economical hard surface
cleaners around. Phosphates have been a tough point for a long time,
but the true culprits (agricultural chemicals) are hardly touched by
it. Phosphates are not banned for industrial in most laundry
situations, nor for just about any hard surface cleaning application.
- --
Rick Theiner
LOGIC, Inc.
LOGIC at skantech.com
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Date: Wed, 5 Aug 1998 21:26:56 -0600
From: Mike Allred <mballred at xmission.com>
Subject: American Brewers Guild-Adv homebrew course
I am seriously thinking about attending the American Brewers Guild 2 day
Advanced Homebrew Course. I have a few questions of the collective first.
Has anyone here ever attended the course, if so what did you think. Was it
worth the $160 + hotel + travel costs? How detailed and indepth is the beer
faults tasting section? Is this just a 'boil/pitch/stir' course or do they
get indepth into the real cutting edge stuff?
Also, is it worth going to the Woodland CA location instead of the Denver
location (Denver is closer for me) to get into the real brewing school?
My beer budget allows for either this course or a keging system. Is it
worth giving up my keg system for now?
- ----------------------
Last night I read the article in Brewing Techniques about Sahti Beer and I
was just fascinated by the idea of 'no boil' brewing. For the moment, I
don't want to brew a real Sahti beer, but has anyone tried
mash/launder/pitch without the boil? I am imagining a FULL BODIED, protein
rich beer that sticks to the top of your mouth with an overpowering malt
taste. You would have to drink it fast, and probably use alot of dry yeast
to beat the infection. What about hop extracts, so you would still have
some bitterness to counter the sweetness? Any ideas?
Mike Allred - drunk as hell on raspberry MEAD
+++
Ocean Size Brewing
'No talking, just all action'
+++
(has anyone noticed that Pat B. has been home alot more lately? - kids are
great)
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Date: Thu, 06 Aug 1998 04:20:08 GMT
From: huskers at customnet.net (Jason Henning)
Subject: Iodophor, Pe^(rt), homebrew twange, celler temps
Hello Friends-
In 2785, Tim Burkhart <tburkhart at dridesign.com> asks about water temp
for Iodophor. The bottle (in pita to read green print) states "add B-T-P
Iodophor to cool or luke warm water. Never use hot water."
The thing I hate about the stuff is the mixing directions:
1/4 oz in 2 1/2 gallons of water
capful = 1/4 oz.
That's not a very easy ratio to use for other volumes. So I made a table
on a sticker and put the sticker on the bottle. I used indelible ink.
Gallons Teaspoons
water iodophor
1 .6
2 1.2
3 1.8
4 2.4
5 3
.42 .25
.84 .5
1.25 .75
1.67 1
2.5 1.5
3.33 2
I grew so attached to my bottle with the table, I refilled it. I spilled
some down the side and the sticker turned black. I was bummed. Then the
next time I used it, all the black had faded and I was joyous (as joyous
as you can be about something like that).
On another note, I was soaking some Martinelly(sp) 7 oz. apple juice
bottles in iodophor. I noticed that the label glue was purple. Does this
indict incomplete conversion? Should I rest the bottles at 155F first?
Are my bottles ruined?
In 2788, Sam Mize says "25% more starter gives you 25% more cells." in
reference to exponential growth. While I agree, we should look at the
implications.
For the sake of argument, assume a wort with no dissolved O2 and two
starters, one with 75 cells and one with 100 cells. As has been well
documented, there is enough sterol for 3 divisions.
That means the 75 cell starter will double to 150, then 300, then 600.
And the 100 cell will double to 200, 400 and 800.
Although the first starter is still 25% less, we're starting to talk
about significantly differing populations. Then when you add O2 and
enable more divisions, the difference in population is even more
dramatic.
I say build a starter as big as you can. Every little bit helps.
And then Brian Wurst says "I would wager that most homebrewers
underpitch almost every time they brew...Could this be the origins of
THT (That Homebrew Taste)??"
Well, in my brewery, it was referred to as Homebrew Twang. I pretty much
eliminated it when I started paying attention to HSA.
And now for my question: I'm using an freezer for 'cellering' my beers
and meads. What temperatures would the collective suggest? I've been
dialed in at about 65F.
Cheers,
Jason Henning
Big Red Alchemy and Brewing
Clawson, Michigan
Reality is an illusion that occurs due to the lack of alcohol. - W.C.
Fields
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Date: Wed, 5 Aug 1998 13:21:10 +0300
From: "Sandy Macmillan" <scotsman at ncc.moc.kw>
Subject: Pressure Drops and Wine
Pressure drop on Coils
I will throw in my pennies worth. When a liquid travels down a tube pressure
is lost to overcome the friction. When the liquid goes through a chance of
direction, at a bend or curve the more pressure is lost to change the
direction of the liquid, thus a coil will always give a higher pressure drop
than a straight length of tube. You can see the effect if you take a poly
tube flowing and then bend it into a coil. The flow rate drops. A full
discussion and calculation methods are available at ASHRAE or CIBSE design
notes.
Stuck Wine
I have had this problem as well. There is no certain way to solve it, but
the most successful way I had was to take a couple of litres of actively
fermenting wine from another batch and add one litre of the stuck. Aerate
and watch carefully, once this is fermenting again add another litre of the
stick. Repeat this until you have about 10 litres of active starter. Aerate
the stuck wine and blend in the starter. This normally shifts the stuck
wine. What is the condition of the bottom of your fermenter. I mean it's
temperature, I find wine is very susceptible to the bottom temperature have
had stuck fermentation because the bottom was too cold.
Regards
Sandy Macmillan
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Date: Wed, 5 Aug 1998 23:10:20 -0700
From: "Brian Dixon" <mutex at proaxis.com>
Subject: Sierra Nevada Bigfoot clone???
Anyone out there aware of a barley wine recipe that comes out fairly close
to Sierra Nevada Bigfoot? I love the stuff! I'm planning on brewing
something as close to it as I can get this fall ... as soon as the weather
cools enough.
Thx,
Brian
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Date: 6 Aug 98 00:08:16 MDT (Thu)
From: rcd at raven.talisman.com (Dick Dunn)
Subject: sulfites, etc.
Sigh...I suppose I should have followed this one longer. I had actually
given up on the thread when Burley first wrote about using sulfiting to
prevent a bacterial-induced off-taste but at a rate that obviously would
not prevent such bacteria, then defended it on a different basis. I don't
have any patience with such duplicity...it's why I've mostly given up on
the HBD.
But ALAN KEITH MEEKER <ameeker at welchlink.welch.jhu.edu> quoted Burley
thus:
> >Although I know this was not your direct point , Dick, I see people are
> >often concerned by the "contains sulfites" label on wine bottles from
> >France. I think this marketing ploy ( like "contains no tropical oils" by
> >US oil producers) by nitrogen-using, large US vintners has gone far
> >enough...
Complete nonsense.
The "contains sulfites" is required by US law if the sulfite level is above
a certain very low threshold...a level that will be achieved by almost any
winemaker using added sulfites, and even some wines that don't have any
added but happen to acquire enough during fermentation. It's legal crap
that has nothing to do with process, safety, or health. It's not a
marketing ploy. It's a legal ploy by legislators manipulated by the tee-
totaler fringe:-) You can sort out this much by digging in to the laws and
finding that only alcoholic beverages are required to warn for sulfite
content at such a level.
The "complete nonsense" comment is aimed at the apparent sulfite-vs-nitro-
gen contrast. Nitrogen is a gas which is inert relative to fermentation
chemistry, but it has nothing to do with combatting bacteria, stray yeast,
or any of the concerns in the original thread. It's a blanket gas.
> >...I have yet to see any reason not to use this simple compound in
> >moderate amounts and challenge anyone to provide me with scientific
> >documentation that it is harmful in the amount that normally occurs
> >in wine...
The two parts of this statement are entirely separate. There is no good
reason to avoid sulfiting in moderation based on any argument that it is
harmful other than to the sulfite-sensitive (who must also be careful of
restaurant salads, etc.). OK, so we're in tune there. But that is off to
the side of whether one should use it in preparation of cider or perry
(remember, that's where this thread started). The droolingly obvious
reason NOT to sulfite a perry is that you'll kill the natural yeast which
might well be your key to a successful slow fermentation.
Back to Alan:
> I don't think this is just a marketing ploy. I believe that the "contains
> sulfites" label serves as a warning to the small portion of the population
> that is sensitive to the presence of sulfites in foods, beverages, and
> medicines...
Back to "nonsense": The warnings are applied selectively to wines. Other
foods which contain much higher sulfite levels are NOT subject to warnings.
I wouldn't mind seeing blanket warnings at some specific level, but what I
(and a lot of other folks) object to is seeing a warning on a wine bottle
which will give somebody x amount of sulfite if he drinks half a bottle,
but not on a salad bar where he'll get (say) 3x amount of sulfite from the
lettuce in a typical salad. Why do the warnings work this way? Because
there are folks who really don't want you to drink alcohol, but they can't
get at you directly, so they use indirect ploys like "contains sulfites".
- ---
Dick Dunn rcd at talisman.com Hygiene, Colorado USA
...Mr. Natural says, "Get the right tool for the job."
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Date: Thu, 6 Aug 1998 17:01:00 +1000
From: James_E_Pearce at nag.national.com.au
Subject: Pitching -- which is better
From: James E Pearce at NAG on 06/08/98 05:01 PM
Friends
Which would be better to pitch, yeast slurry from the secondary or a 1-2
litre starter?
Thanks
James in Melbourne
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Date: Thu, 06 Aug 1998 05:38:32 -0400
From: David Sherfey <sherf at warwick.net>
Subject: Barleywine conditioning
John
My advice is that you have to expect barleywine to take more time to
bottle condition than lower gravity beers; lots longer.
I made a BW eight years ago (Sierra Nevada ale yeast, FG was
around 1.022) that I bottled; some with new yeast only, some with
dextrose prime only, some with yeast and dextrose, and some with nothing
at all. Guess what? They all eventually conditioned nicely. The ones
with new yeast conditioned faster, but I was not sastisfied with any of
them before 9 months. The one with nothing took around two years! I
was able to wait with great patience because I kegged two gallons that
was ready instantly. Interestingly, I CP bottled some from the keg and
they did not display the bottle longevity that the others did, giving up
in four years while the others lasted 6.
Just from my single experience, I would say to add yeast, but I would be
interested to learn what others have to say on the subject.
Cheers!
David Sherfey
Warwick, NY
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Date: Thu, 6 Aug 1998 09:08:42 -0400
From: "Buchanan, Robert" <RBuchanan at ChristianaCare.org>
Subject: Oak in Brewing
In HBD# 2787 Alan Meeker asks about the use of oak in beer. There are a few
"uses" for oak in brewing that I know of.(this is in no way inclusive of all
of them) The most common use is in IPA's. Traditionally oak casks were used
to transport the beer "around the Horn" to India. This imbibed a "oaken"
flavor to the beer. IPAs today have been fermented on oak chips to mimic
this tradition. I've also had Rauchbiers with this subtle note also. Lambics
especially Grand Cru & Guezes are stored in oaken vessles for a period up to
years. On usage of the oak chips I've placed them in the secondary and this
provides a nice note especially in a strong, hoppy IPA.
Alan's reference to a red wine with oaken character might not be directly
comparable to beer because wines contain lots of tannins (especially reds)
which will add to the "oaken" characterisitcs.
Bob Buchanan
"There are TWO rules for success in Life:
Rule 1: Don't tell people everything you know."
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