---

	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:
  bubbles and gas solubility (pretty long post) ("Czerpak, Pete")
  Tomahawk hops ("Don Van Valkenburg")
  re: SureScreen (Jack Schmidling)
  Lifting converted-keg kettles ("Donald D. Lake")
  RE: Sure Screen (LaBorde, Ronald)
  Kettle carmelization for Scottish/Scotch Ales (beanish)
  Mead Questions (Ted McIrvine)
  non-conversion (SClaus4688)
  enzymes ("Stephen Alexander")
  food grade, fast drying, heat tolerant sealant? ("Sandlin, Jonathan Mark - BUS")
  Tomahawk Hops ("Fred Waltman")
  A little N2/CO2 foam decay measurement... (william macher)
  Listermann (John Herman)
  Signed, Sticky Armpits (ThomasM923)
  The Jethro Gump Report ("Rob Moline")
  clear Weizen (ensmingr)
  re: clear hefeweizens ("Anthony & Julie Brown")
  Guinness Heads ("Rob Compton")
  Flux removal (IndSys, SalemVA)" <Timothy.Rhode at indsys.ge.com>
  cleaning crowns (MicahM1269)
  re: Ring Around the Porter ("David Kerr")
  Re: AOB Tax Designation Change (Steve Jackson)


Beer is our obsession and we're late for therapy!

2000 MCAB Qualifiers: Spirit of Free Beer! Competition 5/22/99
(http://burp.org/SoFB99); Oregon Homebrew Festival 5/22/99
(http://www.mtsw.com/hotv/fest.html); Buzz-Off! Competition 6/26/99
(http://www.voicenet.com/~rpmattie/buzzoff)

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----------------------------------------------------------------------


Date: Tue, 4 May 1999 10:17:42 -0400 
From: "Czerpak, Pete" <Pete.Czerpak at siigroup.com>
Subject: bubbles and gas solubility (pretty long post)

A number of people have posted on gas bubbles and bubble coalescence (little
bubbles joining to become big bubbles) and N2 solubility in water/beer.  I
went back to my old physical chemistry book and a few handbooks and here is
what I came up with. i am glad that i can actually use those 2 semesters of
p-chem every once in a while, especially when its brew related. this is a
longer post by the way.

CO2 solubility:
at 45 deg F, 1.33 	at 55 deg F, 1.083

N2 solubility:
at 45F, 0.0199   at 55F, 0.0175

units of solubility for the above are on a volume basis and are mL gas
dissolved measured at standard conditions when dissolved in 1 mL water at
the above given temps when gas pressure is 14.7 psi.

I do have the solubilities over a full range of useful temps and will post
them or a data fit if people are interested in the temp dependence.  data
was taken from Lange's Handbook of Chemistry 14th edition.

Onto bubbles, someone posted a surface tension relationship for bubble
diameter.  yes, there is a pressure difference between the bubble and the
bulk fluid.  it is essentially what keeps the bubble from collapsing on
itself due to the liquid surface tension constantly pulling on itself.
however for small bubbles, this pressure difference is pretty tiny.

for example, in a "beer" solution which I approximated as 95% water and 5%
ethanol and at 45 deg F, a bubble with a diameter of 2 mm yielded a pressure
difference of 0.02 psi between the inside of the bubble and the outside of
the bubble. just for everybodys info: the surface tension of my "beer" at
45F is about 71 dyne/cm and decreases with increasing temperature.

The eqn is called the Laplace eqn and is correctly given as:

pressure inside bubble - pressure outside bubble = 2 surface tension /
bubble radius

>From this you can see that smaller bubbles have a higher difference in
pressure at a fixed liquid surface tension.  Also to note, if you want to
decrease bubble size (ie. make a nice fine head) you need to either lower
your surface tension or increase the pressure difference.  perhaps malted
wheat causes surface tension to lower.  maybe someone could measure the
differece in surface tensions for equal gravity worts, one made with wheat
and one with normal barley.  also perhaps the high serve pressure of
pilsners, etc. helps makes the fine head. 

the driving force behind bubble coalescence is really thermodynamics.
bubbles have a certain surface free energy that always is minimized.  this
is how one actually can derive the above given equation from thermodynamic
principles.  anyways, when 2 bubbles collide and stick, the total surface
free energy is not at a minimum.  from the above always heading towards
minimum total free surface energy idea, the surface area shrinks by the
bubbles walls merging to a new larger single bubble and the total surface
free energy is minimized.

about nitrogen use in Guiness and the like.  I have discussed this with some
co-workers and we have thought that they chill the beer and pressurize the
beer at high gas pressures using the mixed gases to get more of the N2 in
solution.  then the temperature is raised slightly and the pressure let up
so that the beer is supersaturated with N2 in solution.  this is probably
similar to a liquid having more that a soluble amount of solid dissolved in
it where the temp is raised, more is dissolved, and the temperature is
lowered again without the excess dissolved solid material crashing out of
solution.  however, usually for supersaturated liquids, adding just a bit
more solid material in a supersaturated solution will cause large amounts of
solids precipitation.

hope all who wonder now feel enlightened.  and boy do I really feel like a
chemical engineering geek spewing forth all that useful knowledge I thought
i would rarely use. feel free to debate or comment.

Brew on,

Pete Czerpak
pete.czerpak at siigroup.com


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Date: Tue, 4 May 1999 07:48:57 -0700
From: "Don Van Valkenburg" <ferment at flash.net>
Subject: Tomahawk hops

In HBD 3021 someone (didn't put name in post) asks about Tomahawk:

I have heard that Tomahawk are the same as Colombus.
Tomahawk are sold by Yakama Chief and Colombus by Hopunion.
They both are indead super-high alpha hops.

One thing should be known about super-high alpha hops.  They are generally
considered "alpha unstable" that is to say they lose alpha real fast.  If
packaged at 17%, they will be somewhat less when you go to use them -
especially if not kept below 32F.

Don Van Valkenburg
brew at steinfillers.com
www.steinfillers.com





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Date: Tue, 04 May 1999 08:45:44 -0700
From: Jack Schmidling <arf at mc.net>
Subject: re: SureScreen

"Jeff Beinhaur" <beinhaur at email.msn.com> asks

" My last resort is the old "hairy arm" technique....

Not sure what that means but one of the things many folks fail
to mention on the rare occasion that screens clog is that they
used Irish Moss.  Although the last time I said this, lots of
folks said they have no problems, I tried it once and ended up
with a jello coated screen and a hopeless mess.

If your hairy arm is used to scrape the screen while trying to
drain, that too will guarantee failure.  The hops function just
like the grain bed in mashing and any disturbance of the filter
bed will quickly clog the screen.  

Keep in mind, the screen is not the filter, the grain/hops is/are.
All the screen does is keep the crud from clogging the spigot with
the initial rush.

In the event of a clog from hops, gently blowing on the end of the
hose will usually clear it but stirring and scraping will never work.
Some folks swear by whirlpooling but if the wort is given adequate
time to settle, nothing but opening the spigot should be required.

If you are using a pump, then nothing but an act of god should
cause problems.

js
- -- 
     Visit our web site:  http://user.mc.net/arf
  ASTROPHOTO OF THE WEEK:  http://user.mc.net/arf/weekly.htm



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Date: Tue, 04 May 1999 11:47:34 -0400
From: "Donald D. Lake" <dake at gdi.net>
Subject: Lifting converted-keg kettles

After successfully brewing 5-gallon batches with my new converted keg
brewing kettle, I would like to step up to a 10-gallon batch.  I see one
major problem with my current setup--lifting 11 gallons of boiling
liquid up off of the burner to a higher point so I use gravity to run
the hot wort through my counterflow chiller then into the carboy.

With 5 gallon batches, the weight was testing my limits.  I am hoping
someone has come up with a  technique so that two people can lift that
red-hot kettle, safely.

Don Lake
Orlando, FL
dlake at amuni.com




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Date: Tue, 4 May 1999 10:54:36 -0500 
From: rlabor at lsumc.edu (LaBorde, Ronald)
Subject: RE: Sure Screen

>>>>
From: "Jeff Beinhaur" <beinhaur at email.msn.com>

Problem is that lasted about 5 seconds and
then nothing. With all of the hops and I assume break material the
SureScreen was clogged. In the past I've tried a stainless steel scrubby
around the screen and this helps but it still gets clogged. I've tried
whirlpooling but maybe I don't know how to do this either.
<<<<

You said whole hops, so this setup you are using should work well for you.
One thing that happened to me and it may be your problem is that I was using
a racking cane without the end cap with the scrubby screen and clogging was
quick and complete.

What I discovered was that the cane went to the bottom of the screen,
blocking the entrance hole and stopping it up.   Next time I kept the little
cap on the racking cane inside the scrubby, and this prevented the clogging.
Try using the cap next time and don't push too hard on the cane, or it will
go to the bottom of the scrubby. 

Ron

Ronald La Borde - Metairie, Louisiana - rlabor at lsumc.edu



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Date: Tue, 4 May 1999 12:52:18 -0400
From: Jeff Knaggs <jak at absoft.absoft.com>

Subject: RE: MI hops-grower needed 

>herb-farmer, to produce hops on her farm in northern Michigan.  Word has
 ...
>greenhouse.  My mother is in need of advice, however, from an experienced

Tell her to call the county Agricultural College (Michigan State Univ.) 
Cooperative/Extension office.  They were helpful when I decided to put 
a few in my back-yard. If she is serious about quantity, I suggest
she also call an extension office in one of the counties in Washington 
where hops are still a big commerical crop -- they will have lots of 
literature.


Jeff Knaggs


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Date: Tue, 4 May 1999 09:52:10 -0700 (PDT)
From: beanish at blarg.net
Subject: Kettle carmelization for Scottish/Scotch Ales

Someone asked recently about Noonan's instructions in the style
series Scottish Ale book about kettle carmelization.

I've done things that way a couple of times for extract brews, and
what I found worked well was this.  I mixed the liquid from steeping
or partial mash and put it in a 5 gallon pot, added most of my extract,
and filled with hot water.  Once the extract was dissolved, I positioned
this pot above my kettle, started a syphon into my kettle, and lit my
burner.  I'd then add the rest of the water to get up to my boil volume,
any additional extract, and proceed normally.

The first time I tried it I turned on my burner full blast, and it resulted
in a somewhat scorched taste that wasn't entirely pleasant.  I've since
found that a more moderate heat level works wonderfully.  I'm not sure
if it was the carmelization, or the yeast (a Scottish yeast, fermentation
at 58-60F), or what, but my latest Export ale had a wonderful flavor behind
the maltiness that was somewhat smoky, but more balanced and appetizing
than what I've gotten with a peat-smoked malt.  Seeing how nice this came
out, I have no interest in using smoked malts in any future Scottish ales.

I haven't brewed a Scottish/Scotch with my new all-grain setup yet, but
instead of running my first runnings into the kettle (not really practical
anyway for my setup - I sparge into a kettle at ground level and then
lift to my kettle) I'll probably collect a gallon or two, and then do
something similar to what I described above.  Syphon those runnings into
my brew kettle with the heat at a moderate level.

Since I've been brewing this way I've also started washing my kettle with
a TSP solution, seems to be good at removing the small level of scorching
that I get on the inside bottom of my pot from the kettle carmelization.

- --
Jeremy York
beanish at blarg.net


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Date: Tue, 04 May 1999 14:26:59 -0700
From: Ted McIrvine <McIrvine at ix.netcom.com>
Subject: Mead Questions

Honey that has a stronger flavor can be great for meads, although if you
also use fruit, you will hide some of the honey characteristics.  I
prefer to add the fruit to the must (don't boil the honey!) just after
turning off the heat, and I leave it in the primary fermenter for a
couple of weeks.  Try at least two pounds of fruit per gallon unless you
will also use fruit extract at bottling.  If you use more than 2 lbs of
honey per gallon, the alcohol will wipe out any wild yeasts on the fruit
during the long fermentation.  

Don't bug your mead; let it sit in the secondary as long as you can,
especially if you use fruit.  (Six months isn't a long fermentation for
a fruit mead.)  Mead can be bottled as still or sparkling.  Sparkling
mead shouldn't have as much carbonation as beer (it should be similar to
a gently-carbonated cider.)  Depending on your yeast strain and the
quantity of honey, it may be hard to carbonate without force-carbonating
from a keg.  Some meadmakers use gelatin for clarifying, many use
Sparkaloid (tm) which is terrific except it requires multiple rackings.

Cheers
Ted

> From: Thomas S Barnett <barnets at mail.auburn.edu>
> Subject: Mead Questions
> 
> First of all, i found
> some locally produced 'Wildflower and Red Clover Honey' which i was hoping
> to use.  Is this a suitable variety, or should i use the lighter
> varieties?  Secondly, how should fruit additions be prepared, how much
> should be used, and when should they be added?  And finally, what
> carbonation levels are appropriate? Thanks. Tom Barnett.


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Date: Tue, 4 May 1999 16:59:58 EDT
From: SClaus4688 at aol.com
Subject: non-conversion

Greetings fellow brewers.

It's been a very long time since I've made any contribution to the HBD.  I am 
afraid I am coming back under the humblest of circumstances, having just gone 
through the most frustrating brewing session of my decade long (occasionally 
semi-maniacal) homebrewing career.

With all the recent posts about lawnmower beer, and with summer not too far 
off, I decided to try my hand at one.  My grain bill called for 14 pounds of 
Belgian two row pilsner malt, 3 pounds of flaked rice and a half pound of 
carapils for a 10 gallon batch (with the moderate efficiency of my system, I 
was shooting for a SG around 1.047).  I'm no stranger to adjuncts, having 
experimented with corn starch, corn grits, oatmeal, flaked barley and even 
pumpkin.  However, this was the first time I'd used rice, and I chose flaked 
rice specifically because I've read that it does not require a separate 
cereal mash.

I live in Portland, Oregon, which has EXTREMELY soft water (1.8 ppm Ca++, 
0.75 ppm Mg++, 1.6 ppm Na+, 10 ppm Cl2, 0.5 ppm sulfates and 7.5 ppm 
carbonates).  I usually use gypsum to bring the Ca++ level up, but, because 
this was going to be a lager, I used CaCl2 instead.  I'll admit right here 
that I am not even close to understanding water chemistry, but I followed the 
directions on the label of the CaCl2 package which said that adding a 
teaspoon to 5 gallons of water would add 95 ppm of Ca++.

I did an upward infusion mash, starting at 122f, going immediately to 135f 
and resting for 10 minutes, then to 151f for saccharification.

The mash still iodine tested very starch positive 6 hours later.

Why?  That's what I've been asking myself for two days.  I've got four 
theories:

1.  Flaked rice might need some kind of special handling, rather than just 
dumping it into the mash.  Adding credence to this theory is the fact that 
the mash didn't really have much solid in it other than grain husks when I 
dumped it out -- it was just really milky.

2.  The Belgian two row pilsner malt did not have enough diastatic power to 
convert the rice.  I didn't really worry that much about this beforehand, 
because the rice was only about 20 percent of the grain bill.

3.  I did not use enough CaCl2 to allow the mash to acidify properly.  OTOH, 
I've made pilsner in the past with NO water adjustments and it converted fine 
(using a decoction mash).  OTOOH, because it's spring, we're having a heavy 
runoff from the mountains here (our water source) which undoubtedly has an 
affect on both the content and treatment of the water coming out of my tap.

4.  The brewing gods are very angry because I have tried to make budmilloors. 
 

Anybody have any theories of their own?  If I don't figure this out pretty 
soon, I'm going to have to rip out my lawn and sell my mower.

 -Steve Claussen in PDX





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Date: Tue, 4 May 1999 17:47:58 -0400
From: "Stephen Alexander" <steve-alexander at worldnet.att.net>
Subject: enzymes

Marc Sedam writes

>>I agree completely *BUT* starch and
>>particularly amylopectin molecules trap water much more effectively than
 ...
>.  <snip>
>I'm not sure this is true.  In a past life I did a lot of work with
>purified enzymes and their stability in industrial processes.  The
>enzyme supplier (who shall remain nameless) stabilized their enzyme
>preps with sorbitol (a sugar) and some basic antioxidants.  I was trying
 ...


There are two related factors stability and activity.  Sugars, sugar
alcohols and a number of carbohydrate compounds can greatly stabilize
certain hydrolase enzymes. In one paper they suggest that trehalose (a
storage carbohydrate in yeast) is actually more important as an enzyme
stabilizer for dormant yeast than for stored carbohydrate energy value.
Some of the same amylase enzymes that are stabilized by sugars are also
inhibited by them - but that is a different thing.  See below.

So both increased stability and inhibition (lower activity) may occur when
these carbohydrates and sugar alcohols are present.  This isn't
contradictory.

A completely different phenomena was being discussed in my comments above.
Water is required for enzymatic hydrolysis to occur.  Water is just as
necessary for alpha-amylase to act as is starch, and in fact the
relationship between the concentrations of starch and enzyme vs measured
(not specific) activity follow the same kinetic rules as do the relationship
between the presence of free water molecules and activity.  It's referred to
as the Michaelis-Menton equations.  If water concentrations are too low,
the rate of hydrolysis drops off.  The measured activity drops. Most enzymes
are more stable when water is absent, but they are of course inactive
without water.

>Another important aspect of enzyme stability is the existence of
>sufficient cofactors.  Alpha-amylase is stabilized by the existence of
>calcium...yet another reason to make sure your water chemistry has
>sufficient calcium in it (>50ppm).

According to the paper "Calcium Requirement for Stability and Enzymatic
Activity of Two Isoforms of Barley Aleurone Alpha-amylase", J.Biol.Chem,
vol264, #32, pp 19392, 1989 ....   The amount of calcium required for
stability of the least stable barley alpha-amylase (there are several) was
in the range of tens to hundreds of microMols of calcium - no more than 4ppm
of calcium.  You are likely to get this amount from the malt alone.  If
>50ppm were required then Plzen  would be producing starchy beers - they
don't.

Dr.Dave comments ...

>What does happen sometimes is the thick mash impacts
>the rate of saccharification since sugars impede the
>amylases in performing their duties.

This is enzyme inhibition and not what I was referring to.  My comments were
that water is a necessary reactant in any hydrolysis and at mash thicknesses
at and below 1.5qt/lb mashes are demonstrably slowed by the lack of
available  (free) water.

>Interestingly enough ( as often happens in brewing) this is
>not a linear function, as the thicker the mash, the more
>stable the beta amylase. So that, apart from what we
>might forsee as a greater fermentability at higher ratios.
>this is reversed for some cases due to the longer life
>of the beta amylase in the more concentrated mashes
>allowing it to split more of the higher carbohydrates.
>(p. 220 M&BS 1ed, 1971)

I agree, but the explanation contributes to the muddle that persists in most
HBers minds.  Less available water (thicker mashes) does increase stability
AND decrease measured activity.  To understand the final outcome one must
compare the rates at which these occur.  Typically the loss of enzyme due to
temperature related denaturing is the greatest rate determining factor in
the system - a couple degrees C for increase cannot be outweighed by the
other factors under reasonable brewing conditions.

For a given temperature, often, as Dave suggests, increasing thickness gives
more final product (for example a thick 60C mash will allow more of the
protease activity, a thick 70C mash will allow for more beta-amylase formed
maltose than a thin one), but the M-M relationship would indicate that this
won't continue at progressively thicker mashes.  The malt with 4% moisture
in the sack will probably self-convert at room temperature in a few
centuries - but we can't wait than long for beer. Somewhere below 1qt/lb (a
2.0 liquor to grist ratio) the enzyme activity drops off at too great a rate
to be accounted for in terms of improved enzyme stability during a
reasonable length mash.

In one study total extract from PA malt dropped to 70% of the control value,
when thickness was increased to a 0.5qt/lb for a 60 minute, 65C mash.  At
1qt/lb it was up to 96%, at 1.5 qt/lb about 98+%, and essentially 100% at
2qt/lb.  So 1/qt/lb is a reasonable lower bound for all malt mashes.  The
paper also studied mashes with 50% wheat, corn and potato starch added.
All, but especially the corn and potato starches benefited greatly from
thinner mashes above 1.5 qt/lb.

The same source shows that extract dropped by about 15% while mashing 1.25
qt/lb *WHEN* a 10P(10%) sugar solution was used.  The sugar inhibits some of
the enzymes, stabilizes some and traps water molecules.  A comparable (10%)
addition of pentosans, and betaglucans caused about a 25% loss in an
artificial starch+enzyme mash.

In another paper (JIB, v97, pp85) fermentability for a 70C, 1hr mash over a
huge range of thickness [0.5qt/lb to 3.5qt/lb] varied by about +-8%, while
bumping the temperature to 75C caused a 21% to 52% drop depending on
thinness.

>What I do is start with a thick mash to increase
>the concentration of the proteases and stage

It isn't the concentration of the proteases that makes a difference - it's
the lack of water that improves stability enough without dropping activity
too much.

===========
The notes below refer generally to the enzyme class but not to barley
enzymes specifically.  Barley contains several different alpha- and beta-
amylases isozymes.  From Verlag Press 'Enzyme Handbook'

Alpha-amylase:
Inhibitors:
    Hg+, Cu+, Mg+, Ca++, Fe3+, Zn++, Al3+, Ni++,
    salts of the above metals, iodoacetate, ascorbic acid,
    wheat alpha-amylase inhibitor protein, maltotritol,
    panitol, maltose [non-competitive].
Cofactors:
   Histidine, dithiothreitol, mercaptoethanol
  Metal Compounds/Salts:
    Ca++ (requirement for some isozymes, not others),
    Cl- (requirement for maximal activity),
    Ba++ (stimulating effect),
    Fe++ (enhance activity),
    Phosphate (stimulating effect),
    Anions (activating),
    Zn++ (activation)
Stability Info:
    Ca++ - protects against proteolysis, thermal inactivation
    Urea - no denaturing,
    Guanidine hydrochloride - denaturing
    Starch, & enzyme products - stabilizing, prevents heat
         denaturing.
    Na+ - stabilizer, resistance to proteolysis.
    Carbohydrates, Polyols[sugar alcohols] - stabilizers.
- --
Beta-Amylase:
Inhibitors:
    Glucose, Maltose(competitive inhibition), alpha-methyl-
    glucosidase, cyclodextrins, Ag+, Hg++, Cu++, Ni++,
    Fe3+, Mn++, Mg++, CO2- (!!), bacterial beta-amylase
    inhibitor protein. EDTA, Zn++, salts of the metals above.
CoFactors:
    none
Metal Compounds/Salts:
    no metal req for some,
    K+  - reactivity enhancement,
    Na+ - reactivity enhancement,
    Ca+ - reactivity enhancement.
General Stability Info:
    Ca++ - stabilizing
    Freezing - partial denaturation,
    dilution - destabilizing
    [the dilution issue may indicate that beta-amylase is self-
    stabilizing, diluting thus decreases the concentration of the BA
        stabilizer.
- --
 -S







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Date: Tue, 4 May 1999 14:55:08 -0700 
From: "Sandlin, Jonathan Mark - BUS" <SANJM304 at bus.orst.edu>
Subject: food grade, fast drying, heat tolerant sealant?

	I am planning to use one of my boiling pots for a fermenter.  I like
the idea of being able to steam sanitize it.  I would like to find some way
to seal the lid onto the top of my converted keg.  I plan to drill two holes
in the top of the lid for filling and gas releif.  Any ideas on how I can
seal the lid on?  Thank you in advance for your help!

Jon Sandlin
Corvallis, OR 97330


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Date: Tue, 4 May 1999 18:36:06 -0700
From: "Fred Waltman" <fwaltman at mediaone.net>
Subject: Tomahawk Hops


Brewinales asks about Tomahawk hops:

I believe Tomahawk is one broker's (Yakima Chief?) trademark/name  for
Columbus.

Fred Waltman
Culver City Home Brewing Supply (LA Area)
www.brewsupply.com   *and*  www.LABeer.com




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Date: Tue, 04 May 1999 20:03:45
From: william macher <macher at telerama.lm.com>
Subject: A little N2/CO2 foam decay measurement...

Hi All,

Since I have a tank of Nitrogen (not a CO2/N2 mix) and a 
CO2 tank, I decided to try a little test to see if there would 
be noticeable difference in the rate of collapse of the head 
of glass of beer comprised of CO2 bubbles, as compared to 
a head of mainly N2 bubbles.

I used a 20-ounce English-pub-style glass, and a can of Iron 
City Light beer.  I first poured the 2 inches of beer into the 
glass. After the head collapsed I  marked the level, inserted 
a .5 x 1.0 inch airstone and bubbled N2 into the beer until 
the foam filled the glass to the rim.  Nearly all the beer was 
turned to foam in order to fill the glass. The airstone was 
removed. I started my stop watch at that point and timed 
the decay of the foam.

After 10 minutes, the N2 foam was about half gone as far 
as height goes, but there were areas under the top of the 
foam that showed more decay than others. Perhaps this is 
because of the foam was actually a combination of N2 and 
CO2, the result of my starting with carbonated beer.

I dumped the glass at this point, rinsed it with cold water, 
and refilled it with 2 inches of I.C. Light, let the head 
collapse and repeated the above procedure.

After 2.5 minutes elapsed, the CO2 foam had collapsed to 
about the same level that the N2 foam had been at after 10 
minutes.  After 6.5 minutes the clear surface of the beer 
began to show. At minute 10, about 60 percent of the beer 
surface was clear, and only about one or two tablespoons of 
foam remained.

So indications are that N2 bubbles do indeed decay at a 
slower rate than C02 bubbles...

I know this has been said many times...somehow the debate
on bubble tensions and differential pressures and such 
left the question unanswered in my mind...so now we have 
a crude measurement that indicates this is indeed the case.
For whatever that is worth...

And no, I do not drink I.C. Light. I keep it on hand for my 
non-beer-drinking friends...:-)

Bill

Bill Macher   Pittsburgh, PA   USA

Bill Macher   macher at telerama.lm.com  Pittsburgh, PA   USA


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Date: Tue, 04 May 1999 22:54:30 -0400
From: John Herman <johnvic at earthlink.net>
Subject: Listermann


Is there an email address for Listermann products?
- --
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
* Bicycling, Bassing and Brewing *
*                                *
*        The Real 3 B's!         *
*                                *
*          John Herman           *
*     johnvic at earthlink.net      *
//////////////////////////////////




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Date: Tue, 4 May 1999 23:53:11 EDT
From: ThomasM923 at aol.com
Subject: Signed, Sticky Armpits

Jeff Beinhaur wrote in HBD# 3021:

"...confidently place the fill tube from the pot into the carboy opened the 
valve and a strong flow began. Problem is that lasted about 5 seconds and 
then nothing. With all of the hops and I assume break material the SureScreen 
was clogged.My last resort is the old "hairy arm" technique to keep the 
screen from clogging..."

My suggestion is to use an NHU (non-hairy utensil) instead of your arm (seems 
like a lot of people are sticking their arms into otherwise sterile wort 
these days---geesh). I scrape the assorted gunk off the screen with my 
brewing spoon.

Of course a big winking smiley face goes right about here --->

Thomas Murray
Maplewood, NJ


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Date: Wed, 5 May 1999 00:55:13 -0500
From: "Rob Moline" <brewer at isunet.net>
Subject: The Jethro Gump Report

			The Jethro Gump Report

Nitrogenation
	 at  the recent CraftBrewers Conference in Phoenix, Matt Brynilson presented
his paper, "Nitrogenation- Practical Nitro-Brew Production."
	With his permission, I am going to detail the hand-out that he distributed.
Perhaps later, I will scan it and place it on the Web, so that you will be
able to see the graphs, we'll see. The audio tape recording of the
discussion is available from Tree Farm Tapes,
http://www.treefarmtapes.com/catalog/conference.asp?conferenceid=585 or
(800)-468-0464. Tapes sell for 9$US, plus 2$US S&H. Matt has also graciously
agreed to discuss this with you, and you may contact him  at 
mbryndil at gooseisland.com
	In the following any comments in < > are my own words from my memory of the
discussion, and should not be construed as Mr. Brynildson's.

		"Nitrogenation Defined
 - Solubilization of nitrogen gas into beer in the presence of CO2 and the
stabilization of that solution until dispense.
 - Modern Method of Cask  Style draft and Dispense.
 - A successful nitrogenation program extends all the way to the glass.

		Enhanced Drinkability
 - Visually stimulating dispense - "Theater Of Pour"
 - Increased Head Retention
 - Rounder, smoother mouthfeel
 - Less carbonation

		Background
 - Arthur Guinness Ltd., the father of Nitrogenated beers.
 - Was discovered through experimentation with early pressurized dispense.
(1950's)
 - American publicans use mixed gas to stabilize carbonated products. <For
example, in a long line draft system; one that needs a lot of pressure such
as in overcoming a high static head--like when the kegs are in the cellar
and the draft towers are upstairs; or in any system where the product is not
served in a rapid fashion. This is to prevent increasing saturation of the
beer with CO2 from the pressurization need to drive the product, not to
nitrogenate the beer.>

		Recognized Products

Product			CO2			N2

Smooth			1.2 v/v		20-24 ppm
 at 48F				(2400ppm)

Super Smooth		1.0 v/v		35-40 ppm
 at 48F				(2000ppm)

Hybrid			1.0-1.2 v/v		35 ppm +
 at 38-45F			(2000-2400)

		Physical Properties

GAS		Dissolution Coefficient		Atomic Weight

CO2			1.405					44.011

N2			0.020					28.01

 - Nitrogen 70% less soluble than CO2.
 - Nitrogen 78% of the air we breathe.

		Relative Units Chart
<Here follows a chart that demonstrates the proportions of CO2 and N2 in
blended gas beers vs Normally CO2'd beers....>

		Henry's Law
 - P = kC
 -Concentration of dissolved gas is proprtional to the partial pressure of
the gas phase.
 - Dissolution constant is temperature dependent.
(Chart)

		Dalton's Law
 - P(system) = P1 + P2 + P3
 - Total system pressure is equal to the sum of the partial pressure.
 - Independent equilibrium is established  betweem the gas and liquid phase
for each gas

	HEAD SPACE
		P-CO2				P-N2
		/| |				/| |
		 | |				 | |
		 | |				 | |
_____________|_|_____________________|_|___________
		 | |				 | |
		 | |				 | |
		 | |				 | |
		 | |/				 | |/
		D-CO2				D-N2
	AQUEOUS PHASE

		Applicable Gas Law Rules
 - Solubility is Pressure dependent
 - Solubility is Temperature dependent
 - Solubility of each gas is independent of the partial pressures of other
gases in the system.

		So That...
 - CO2 cannot be held in aqueous solution with N2 head pressure.
 - N2 cannot be held in aqueous solution with CO2 head pressure.
 - Mixed gas must be used for stabilization to lock in the equilibrium we
want to establish.

		Foam Physics
 - Foam Formation..............Increased by N2 gas breakout.
 - Drainage....................Exaggerated (surge)<cascade>
 - Coalescense.................Slowed by N2/Air equilibrium
 - Disproportion...............Slowed by N2/Air equilibrium

		Natural Foam Enhancement
 - Mashing to Malt Analysis
 - All Malt Beers
 - Wheat
 - Hop Extracts (Hexa-Hydro-co-Humulone)
 - Dry Hops
 - Raw Barley
 - Oatmeal

		Foam Depth Control
 - Target D-N2 levels should be above 25 ppm (prefer 35 ppm+)
 - D-CO2 levels can then be used to adjust the foam depth.
 - Higher D-N2 levels require lower D-CO2 to obtain satisfactory foam depth.
 - Individual brewery must decide on the "proper pour."

	This is not the end of Mr. Brynildson's paper, but the rest focuses on the
practical, and safety oriented issues involved. But a read of recent HBD's
displays lots of discussion, so I will add my .02 again to a few of them...
	1) I can confirm that the nitrogen is not mixed into the solution  at 
dispense. It comes out of solution upon dispense.
	2) There is no gas in the widget before the tin is filled with product. It
is empty, with a 0.6 mm hole laser drilled into it. The dosing of liquid N2
forces liquid, CO2 and N2 in.
	3) There is no dual dip tube in a Guinness keg, simply the same beer out
tube from the bottom of the keg, and a gas in port in the body of the valve
 at  the top of the keg.
	4) Nathaniel Lansing hits the nail on the head in his discussion of gasses
not popping out of solution instantly....the holes in the sparkler/creamer
plate in a Guinness style faucet 'shear' the gasses out of solution. And
gee, they look to be...oh, well, I'd say they look about...ah, could it
be??....0.6 mm?????
	But I do have a place in my head, as unscientific as it is that sez that
the N2 would leave, without the sparkler, more rapidly than CO2, purely a
guess. After all you gotta work so much harder to get it in, so it just
seems obvious to me that when you remove the stabilizing partial pressure of
N2 in the head space.

	Anyhoo, that's it for me on Nitrogen. I do want to say thanks to the folks
 at  the CraftBrewers Convention, especially Dave Edgar for throwing a great
event, and to Brian Rezac for his ongoing work for Big Brew 99. It was a
blast to be linked to others around the world for the Toast, even though we
couldn't brew there.

Cheers!
Jethro Gump

Rob Moline
brewer at isunet.net
Lallemand Web Site
jethro at isunet.net

"The More I Know About Beer, The More I Realize I Need To Know More About
Beer!"



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Date: Wed, 05 May 1999 02:25:17 -0500
From: ensmingr at npac.syr.edu
Subject: clear Weizen

Fred L. Johnson wrote about his clear homebrewed Weizenbier in HBD
3022-12 http://www.hbd.org/hbd/archive/3022.html#3022-12 .

It is a common misconception that Hefe Weizenbier *must* be cloudy to be
true to style. I lived in Germany for about 2 years and consumed many
different commercial Weizenbiers, some brewed in the very town where I
lived, others brewed elsewhere in Germany. All bottled versions were
clear if poured carefully from the bottle into the glass; in other
words, there is no evident protein haze or yeast haze. However, it is
common practice to pour a bottle of Weizenbier into the glass with great
flourish so that the yeast at the bottom is suspended, giving the beer a
very evident yeast haze.

Cheers!
Peter A. Ensminger
Syracuse, NY
P.S. Fred - I really love Weizenbier ... can I stop by for one next time
I'm in Apex, North Carolina?




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Date: Wed,  5 May 1999 03:12:36 CSTCDT
From: "Anthony & Julie Brown" <brown32 at web1.ecol.net>
Subject: re: clear hefeweizens

Here's my limited but similar experience with this subject...

I have brewed a few wheat beers with #3068 myself, using 65% wheat
extract and all have turned out clearer than some non wheat beers
I have brewed.  I thought this odd myself, hoping to encounter
a traditionaly cloudy brew.

I have just finished an apricot wheat with the same 65% wheat extract
but tried the wyeast Irish Ale yeast(they were out of any bavarian 
yeasts or american "chico") and it turned out wonderfully cloudy
with no signs of clearing and now it it's second week in the keg.

I haven't given much thought to why, but have been blaming it
on the yeast strains since I used the same extract in each brew.
At least you are not alone in your experience...


Tony B.


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Date: Wed, 5 May 1999 10:21:36 +0100
From: "Rob Compton" <Compton at btinternet.com>
Subject: Guinness Heads

Hello from good old Blighty!

I asked the landlord of my local pub (some 100 yards the other side of the
road), what he uses to propel the liquid genius from it's barrel.

As with all of his kegged beer, it's "powered" by the same CO2 manifold
system as usual. No Nitrogen here!

I've tried brewing Guinness style beers in the past, and have copied the
bottled styles quite successfully, but can't get the head right on the
draught style.

I use the right malt, the right hops, and what's more the genuine article
flaked barley ("found" at one of the own maltings!!), water treatment is OK,
sanitation is fine, etc... but no creamy head, not that lasts very long.

I think I boiled my last batch for too long as it's head retention is poor,
but it tastes fine, so what the heck!

I have found that running higher pressure for delivery, and a smaller nozzle
in the tap makes a lot of difference.

Proper pub beer fonts have their own pressure regulators at the tap. I have
a couple that need installing in the house (right next to the arm chair!),
so I'll see what happens when I use one.

I usually deliver the beer at around 10psi, compared to around 5 for
ordinary ales, wheat beers & lagers.

Happy brewing.

Rob.




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Date: Wed, 5 May 1999 07:03:00 -0400 
From: "Rhode, Timothy J (IndSys, SalemVA)" <Timothy.Rhode at indsys.ge.com>
Subject: Flux removal

I am in the process of building a RIMS and working on the keg plumbing.
I've been sweating copper piping/fittings using lead free solder.  I've also
been using flux to make the job easier.  Does anyone know what I need to do
to get rid of the extra flux?

Tim Rhode
timothy.rhode at indsys.ge.com


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Date: Wed, 5 May 1999 08:24:31 EDT
From: MicahM1269 at aol.com
Subject: cleaning crowns 

>Rob recently posted:

>"I'm wondering if anyone has asked a micro or a major on how they clean
>theirs. I have askedand this 1 (one) micro said that they didn't. They dump
>them right out ofthe freshly opened box and cap them without cleaning any of
>them."

I have worked at various breweries, large and small over the last 10 years. I 
have never seen any packaging operation clean or try to sanitize crowns 
(bottles) or ends(cans) or caps(screw off). Nor have I heard or read about 
any contamiation or spoilage that has been attributed to the above mentioned 
closures.

IMHO the risk of damaging or compromising the crown as a result of boiling or 
chemical cleaning is far greater than the risk of spoilage from the crown 
itself.

micah millspaw - brewer at large


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Date: Wed, 5 May 1999 09:37:59 -0400
From: "David Kerr" <dkerr at semc.org>
Subject: re: Ring Around the Porter

Patrick writes:

>After bottling a recent batch of Papzian's Silver Dollar Porter I
noticed a
>small ring around the bottle neck at the top of the liquid level.
The beer
>came out nicely as far as my buds can detect, but I thought that I
>remembered reading this was a sign of infection.  I looked in
Miller's book
>and he lists two possible causes: infection and break formation.

I seem to recall a comment a year or so back that using DME to prime
can cause this.

Dave Kerr - Needham, MA



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Date: Wed, 5 May 1999 07:02:26 -0700 (PDT)
From: Steve Jackson <stvjackson at yahoo.com>
Subject: Re: AOB Tax Designation Change

In HBD #3022 (May 5, 1999), Paul Gatza writes:

>>>>

<snip>

     Although we have done limited lobbying in the past, the new status
allows us to lobby without restriction. July 1 is not only the day of
our new tax status, it is also the effective date for legalized
homebrewing in Idaho. As of this writing, the states of Alabama, Iowa,
Kentucky, Mississippi, Ohio, Oklahoma and Utah still prohibit
homebrewing. We can take a more active role in these states as our
budget allows if our involvement is requested by AHA members who
volunteer to lead the effort to legalize homebrewing in these states.
This change gives us the ability to fight against a potential
neo-prohibitionist against the freedom to homebrew legally that most of
us enjoy. 
<<<<

Before the AHA sets its sights on lobbying and such, perhaps it should
pay more attention to providing the basic assistance for homebrewing
legal efforts that it currently promises but consistently fails to
deliver.

Thanks to the efforts of several dedicated Indiana homebrewers (and in
spite of the AHA's failure to provide even basic assistance), as of
July 1 several changes will be made to state law regarding homebrewing.
While it has long been legal to make homebrew in Indiana a strict,
literal reading of the law made it illegal to take any of the beer out
of one's home. As a result, competitions were not legal, and
technically homebrew club meetings were illegal as well. A friend of
mine was even threatened with arrest for "bootlegging" if he handed out
samples of homebrew at a class.

As of July 1, state law will allow the removal of homemade beer and
wine for purposes of education, evaluation, etc. This will make
competitions legal and possible, and put the stamp of legality on club
meetings. The new law will also allow brewpubs, bars, etc. to host club
meetings without risking the loss of their license. And no worries
about bootlegging indictments, either.

This is the result of three years' worth of effort by several
homebrewers and one dedicated legislator (for all you Indiana folks
reading this, drop a note of thanks to State Rep. Brian Hasler from
Evansville). During each of the three sessions that this legislation
has been considered, we have requested some assistance from the AHA.
During each of three sessions, we have received little or no assistance
or support. The most we ever received was a generic fact sheet about
homebrewing in the U.S. No Indiana-specific information, no mailings
sent out to Indiana AHA members to alert them of the pending changes,
nothing. This despite several notifications to AHA folks, including
Paul Gatza.

This is pretty basic stuff, and it's what the AHA is already supposed
to be doing, according to its promotional materials (if I recall
correctly, the folks in Idaho received the same minimal response from
the AHA in their legalization efforts). If the AHA can't handle simple
tasks such as this, I'd hate to see how badly it would bungle organized
lobbying efforts.

I have no reason to doubt Paul Gatza's sincerity when he says he is
trying to make the AHA more responsive to members' needs (for the
record, I am not a member, but the lead person in the legalization
effort is, and our local club is AHA-affiliated). However, the AHA
should stop thinking about what it might be able to do in terms of
expanded efforts when it can't even get its current core duties done
properly.

 -Steve in Indianapolis

_________________________________________________________
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