---

	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:
  (Fwd) Best of Brooklyn Homebrew Competition (George De Piro)
  Neophytes; newbie caramel; whack Jack; overcarbonated keg (Samuel Mize)
  MixMasher Motor? (Mark Kirby)
  "oven mashing" ("Michael Gerholdt")
  MashMixer Motor Movement (KennyEddy)
  dreaded thiobacillus (David C. Harsh)
  Oh, no! Not the Blue Moon thread again. (Kit Anderson)
  RE: Sanitizing Plastics (David Conger)
  Oven Mashing/Lower Extraction? (Lorne P. Franklin)
  Late Hop Additions (Rust1d)
  Change in US Propane Regs ("RANDY ERICKSON")
  Mash mixing speeds (John Wilkinson)
  Diacetyl Question/Stir Bars (AJ)
  Re:Subject: Air Space in Bottles; Blue Moon/Celis/Hoegaarden Whit ("Houseman, David L")
  Subject: Re: Blade Shearing / HSA ("Houseman, David L")
  Brewpubs NJ/NY (Jeff Foley)
  Nightmare (dajohnson)
  Re: Newbe step mashing ("David L. Thomson")
  1997 Bitter Mania Results? (Paul Henning)
  Re: Magnetic Stirring, Copper bottom, Fuller's clone (M Gates)
  Chiller design and keg conversion (Margie and Dave Ludwig)
  Faucet cleaning (AllDey)
  Protein Rest Quiz (Kyle Druey)
  The disadvantages of step mashing. ("Braam Greyling")
  John Bull Wheat Syrup (Dave Bartz)
  Practical Boundary Layers (Charlie Scandrett)
  Siebel Short Course Textbooks (Glenn Raudins)
  RE: Will any CO2 do? (Randy Lee)
  O2 and Yeast (thread anyone?) (Charlie Scandrett)
  Zima Brewing (Glenn Raudins)
  O2 Again ("Little, Wayne")



Be sure to enter the...
The Best of Brooklyn Homebrew Competition
Brooklyn Brewery, Brooklyn, NY
Entries due by 1/31/98, competition 2/7/98
Contact Bob Weyersberg at triage at wfmu.org for more info.


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


Date: Sat, 17 Jan 1998 14:33:04 -0500
From: George De Piro <gdepiro at fcc.net>
Subject: (Fwd) Best of Brooklyn Homebrew Competition

The deadline for entries is fast approaching for the
Best of Brooklyn homebrew competion, sponsored in
part by Brooklyn Brewery.  Here are some of the details:

* deadline for entries is Jan. 31, 1998
* each entry needs to include two (2) bottles
* entries are $5 each; if 5 or more entries are entered, the 
fee is $4 each, with a maximum fee of $40 (entries beyond
10 in number are free)
* all manner of bottles are acceptable, as long as they contain
at least 10 ounces and no more than 1 liter of beer, and the 
bottle doesn't have any label on it
* PET bottles with carbonators will be accepted and carbonators
will be returned if the entrant supplies a S.A.S.E.
* the contest takes place on Saturday February 7, 1998 at the
Brooklyn Brewery in Brooklyn, NY

The Best of Show prize is a $150 gift certificate to A Hop, Skip
and a Brew homebrew supply shop (they ship) and a year's free
entry to all Brooklyn Brewery events (out of town winners will
be given a choice of a optional prize).

We expect to give prizes for every category, and some of the
prizes so far include: shirts, hats, glassware and other 
merchandise from Hopunion USA, Rogue Ale, Briess Malting, Magic
Hat, and others; over 40 POUNDS of various hops from the Boston
Beer Company and Hopunion USA; carbonators and tote bags from
Liquid Bread; high quality beers from B.United, Phoenix Imports,
and others; gift certificates for  Redhook Brewery Crosby & Baker 
and others; a slew of homebrew equipment from shops like Karps 
Homebrew and Hop & Vine; gift certifcates to NYC area bars and 
brewpubs such as the Gate among many more.

Drop off points include: Hop, Skip & a Brew in Queens, NY; 
Hop & Vine in Morristown, NJ; Beer Gear in Wayne, NJ; 
East Coast Brewing Supply in Staten Island, NY; and others.

For more information or for entry forms, write, call or
email:

Bob Weyersberg, Malted Barley Appreciation Society
email: triage at wfmu.org
post: c/o Triage, 133 W. 25th St. #8E, NYC, NY 10001
tel.: 212.989.4545

************************************************************

Chicago area homebrewers:  if you wish to enter this gala event, you
can arrange to give your entries to George De Piro up until Friday,
Jan. 24. 
 George can be reached at mailto:gdepiro at fcc.net or at the Leaning
 Tower 
Hotel, 847-647-8222.

George will transport your entries back to Brooklyn and give them the
same love and care that you would.

Have fun, and good luck!

Return to table of contents


Date: Thu, 15 Jan 1998 08:47:40 -0600 (CST)
From: Samuel Mize <smize at prime.imagin.net>
Subject: Neophytes; newbie caramel; whack Jack; overcarbonated keg

Greetings to all, and especially to:

> HOMEBREW Digest #2609               Wed 14 January 1998


How about adding, up at the top, a pointer to some web resources for basics?
For instance:

 "Many basic brewing questions are answered at:
    http://www.brewery.org/brewery/Library.html"

This would help neophytes, might reduce newbie-question bandwidth, and
would discourage nobody from posting.  Anyone dislike this idea?

 - - - - -

> Subject: Re: newbie questions (LONG)
 ..
> > 3.  I use two burners on my gas stove to heat/boil my wort.  I get 
> >some 'burning'  (carmelization?) on the bottom of the pot,
 ...
> Easiest 
> fix is to put a trivet or zig-zag bend coat hanger wire on the burners

I don't think this will work on a gas stove.  (I use canning-jar rings
around my ELECTRIC elements to lift my pot up 1/8 inch from them.)

Unless you have a caramel or burnt taste in your beer AND you dislike it,
ignore the caramelization.

With gas, I'd say:

The bottom layer of wort can heat up, thicken (so it doesn't rise), and
caramelize.  The solution is to stir.  You don't want to add air to hot
wort -- try not to roil up the surface, just stir across the bottom.

You might leave the lid 75 percent on, and stir through the opening.
This will:

* retain heat, so you need less heat input to maintain your boil, so the
  bottom layer is less likely to caramelize

* put a blanket of steam above the wort, so it gets less exposure to air

* prevent DMS buildup (the steam can still escape).

BEFORE THE BOIL, stir the bottom frequently.  DURING THE BOIL, let a good
rolling boil stir it for you.  If your stove won't maintain a rolling
boil, you'll still need to stir.

 - - - - -

> From: Jack Schmidling <arf at mc.net>
> Subject: Trademarks, HSA

> I highly recommend that you post it publicly.

If someone can't be bothered to send me one crummy email they won't pay
attention anyway.

> It will
> save tons of hateful postings castigating the evil wrongdoer and no
> doubt assure his total banishment.

Great, another cretin saying we should banish Jack!
:-) [Smiley provided for the humor impaired per ADA]


> "Fight Spam - see http://www.cauce.org/
> 
> I find the best way to fight spam is to EAT it.

Perhaps, Butt the Great,
[retry]
Perhaps, but the great thing about CAUCE's proposed law is that it does
NOT ask the government to regulate the net.

 - - - - -

> From: "David R. Burley" <Dave_Burley at compuserve.com>
> Subject: Over-carbonated Cornie,refrac/SG ,MonsterMash-er, pH

> over-carbonated a naturally carbonated Cornie of lager
 ...
> Any ideas on how to deal with this?  I thought about putting an
> extra long hose
 ...
> I could also do this with a keg to keg transfer and this may be easier.

No experience, just theory.  Can you put a hose to another keg, pre-fill
that one with CO2, and let this one foam out into it?  Once it settles,
dispense it back to the first keg.  That should eliminate the excess CO2
without getting much air into it.

Best,
Sam Mize

 - -- 
Samuel Mize -- smize at imagin.net -- Team Ada
Fight Spam - see http://www.cauce.org/
Personal net account - die gedanken sind frei

Return to table of contents


Date: Thu, 15 Jan 1998 10:15:00 -0500 (EST)
From: Mark Kirby <mkirby at bgsm.edu>
Subject: MixMasher Motor?

Hello HBDers,

I've been reading with great interest the recent thread on the mixmasher. 
Has anyone tried adapting a motor from an ice cream maker? Lots of people 
in the south have these things just lying around during the prime 
cold weather brewing season. Should have plenty of torque but may be a 
bit slow, I'm not sure. Just thought I'd throw it out.

Todd Kirby

Return to table of contents


Date: Thu, 15 Jan 1998 10:27:59 -0500
From: "Michael Gerholdt" <gerholdt at ait.fredonia.edu>
Subject: "oven mashing"

Greetings!

I've found it convenient to oven mash as have others. However, I don't
leave the oven on during this time. Prior to putting the kettle in the
oven, I heat it to about 200F. When I put the kettle in, the oven is off.

Think about how hard it is to raise the temp a couple degrees in the mash
when stirring on the stovetop with direct heat.

The thermal mass of the mash is such that when it's sitting in ambient
temps which start at 200F and slowly drop over the next hour, it's not
going to absorb enough heat to raise the temp. Perhaps just a little at the
edges. The entire mash won't go up by a full degree.

It certainly won't *lose* any heat, either. Just make sure that the oven
has held at 200F for a long enough time that it's thoroughly heated itself.
10 minutes or so should do. Then turn it off. Stir the mash three or four
times during the rest. Test the temp each time, both before and after
stirring.

Works for me -

Michael Gerholdt in western New York

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Date: Thu, 15 Jan 1998 10:55:12 EST
From: KennyEddy <KennyEddy at aol.com>
Subject: MashMixer Motor Movement

Jethro writes:

  	Oh, yeah, with mixing the mash, it is recommended that tip speeds of mash
  mixers remain under 3 meters/second. This is to eliminate vortexing, and
  hence HSA, (though we are taught that there is MUCH more benefit to

This is about 200 rpm for a 12" diameter blade.  I believe JS' system uses a
30 rpm motor.

*****

Ken Schwartz
El Paso, TX
KennyEddy at aol.com
http://members.aol.com/kennyeddy

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Date: Thu, 15 Jan 1998 10:59:46 -0500
From: David.Harsh at uc.edu (David C. Harsh)
Subject: dreaded thiobacillus

George de Gump wrote-

>there are bacteria called thiobacillus that produce sulfuric acid and therefore
>destroy stainless steel.

He's right!  And boiling won't help because there are bacteria called
sulfolobus that live in hot springs.  Other species live near hydrothermal
vents on the ocean floor so we can't kill them with pressure.  And they're
all facultative anaerobes so depriving them of oxygen won't help.  But the
worst thing is their staining reaction - under microscopic examination:
plaid.  Face it, we're screwed.

Dave

                         Dave Harsh
          Bloatarian Brewing League; Cincinnati, OH
 Everyone has a photographic memory.  Not everyone has film.
                              O-



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Date: Wed, 14 Jan 1998 23:13:42 -0800
From: Kit Anderson <kitridge at bigfoot.com>
Subject: Oh, no! Not the Blue Moon thread again.

Charles L. Ehlers wrote;

> Celis seemed much
> closer to a high quality American wheat--readily available from brew pubs in
> Kansas--than a Belgian.
>   All good beers.
>   So, for those who say "pwit" is the last sound heard before Blue Moon hits
> the ground, what Makes it so inferior and the others so superior?

It is a style question. Celis and Hoegaarden define the style. Blue Moon
is "lite" wit.
Not enough spice, acid, esters, or gravity. That doesn't mean you can't
like Blue Moon. It is just not the best example of a Belgian wit.

American wheats are not supposed to be estery, acidic or have any
spices. Blue Moon is closer to that than any of the Belgians.

Another point...wits are supposed to be drunk fresh. They do not age or
travel well. 3-4 weeks is about all. After that the spices and esters
decrease. I think that if you were to taste side by side fresh draught
versions, the difference would be more than evident. 
- -- 
Kit Anderson				ICQ# 2242257
Bath, Maine				<kitridge at bigfoot.com>
		got beer?


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Date: Thu, 15 Jan 1998 12:42:16 -0500
From: David Conger <dconger at roadshow.com>
Subject: RE: Sanitizing Plastics

In HBD 2610, Jim Liddil writes, "I have also been suing PBW to clean all
my equipment."

Wow! Let us know if you win your case. I may try suing Muton & Fison to
get them to do my mashing for me.
(Hee, hee. I know it was just a typo, but I couldn't resist. Sorry.)
David

Return to table of contents


Date: Thu, 15 Jan 1998 13:01:04 -0400
From: lachina at mindspring.com (Lorne P. Franklin)
Subject: Oven Mashing/Lower Extraction?

Mark says: "I mash in a SS pot.  Once I've reached my target temperature
(either through infusion or kettle heating) I just place the whole pot into
the oven."

Fred replies: "I have been doing the exact same thing for about a year now
and I have had no problems, although my oven barely gets low enough.  I
suppose one could simply open the oven door a bit if the oven tends to get
a little to hot."


Greetings! After reading many good reports on this technique I gave it a
try. It's great to stop home at lunch and set up the mash, then come home
after work to a finished mash. I get to sleep at 11:00 on a weekday brew
night instead of 2:00.

I've done three extended oven batches with success, but have encountered a
lower extraction rate than I normally have. Has anyone else noticed this?
I'm guessing that not stirring the mash is partly to blame. I've also used
a thicker water/grain ratio to contain the mash in a small enough pot for
the oven. This might be a factor in reduced extraction too.

Otherwise, the beers taste exactly the same as other generations of the
same recipes and there's certainly no lacto/sour taste caused by bacteria
growing over the course of 5 or 6 hours. I'm going to stick with this
procedure for some of my beers and just throw in another pound or two of
fermentables (small pot permitting).

Adios.


Lorne


nailed a retread to my feet
and prayed for better weather



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Date: Thu, 15 Jan 1998 13:27:52 -0500 (EST)
From: Rust1d <rust1d at usa.net>
Subject: Late Hop Additions

Reading Dr Fix's latest book brings up a question about late hop additions
being detrimental to beer.

To get a fuller hop aroma/flavor I have taken to using 3 hop additions at
the end of the brew. In my 12.5 gallon APA recipe I have been adding 60
grams of hops at 20, 10, and 1 min from the end of boil. I am wondering if
this is overkill? I will be brewing this recipe at a local brewpub scaled up
to 7 barrels which equates to about 2 lbs of hops per addition. Is this
wasteful? Would these additions be better suited at 30, 15 and 1 min? What
amounts/times do those who professionally brew use for late additions?

I know that this is not the worst thing that can happen (the brew did win
1st) but am wondering if these late additions are wasteful and if there is a
better way. 180 grams of hops costs me next to nothing but on a commerical
level this could be cost prohibitive.

John Varady                     http://www.netaxs.com/~vectorsys/varady
Boneyard Brewing                The HomeBrew Recipe Calculating Program
Glenside, PA                    rust1d at usa.net                                 


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Date: Thu, 15 Jan 1998 10:32:03 -0800
From: "RANDY ERICKSON" <RANDYE at mid.org>
Subject: Change in US Propane Regs

Got a bit of a shock yesterday when I had my old (circa 1984) propane tank =
inspected and refilled.

According to the propane jockey, new (U.S.) regulations go into effect =
April 1, 1998 which require any propane tank put into initial service or =
inspected and returned to service to have a new type of check valve.  Said =
new valve is rumored to cost about $40.

Since brand-new 5 gallon tanks (with valve) can be had for around $20, =
this will be a rude awakening.  "New" tanks are good for 12 years before =
requiring inspection, and used tanks are good for 5 years.

I don't have any firm evidence to back this information up, but it may be =
worthwhile to pick up additional tank(s) before the end of March.

I have no affiliation with any supplier of propane or propane accessories =
(but I wish I had something to do with selling those new valves  ;-)=20

Randy in Modesto

1987 miles WSW of Jeff Renner,
5182 miles SSW of the Old Brewery, Tadcaster,
No idea where Dave Sapsis is this week.



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Date: Thu, 15 Jan 98 12:47:02 CST
From: jwilkins at wss.dsccc.com (John Wilkinson)
Subject: Mash mixing speeds

I had mentioned in an earlier post that I had had problems with stuck runoffs
and had attributed it to too fast a mixing speed with my contrived stirrer.
This seemed confirmed by Charlie Scandrett's post concerning shear and mash
glucans and/or by Hubert Hanghofer's post concerning aeration of the mash and
its resultant glucan and teig production.  Now Jethro dePiro notes that
according to Siebel:

>	Oh, yeah, with mixing the mash, it is recommended that tip speeds of mash
>mixers remain under 3 meters/second. This is to eliminate vortexing, and
>hence HSA, (though we are taught that there is MUCH more benefit to
>reducing O2 elsewhere in the process), but that excessive shear can "ball"
>up the proteins around the starches, inhibiting conversion, and have a
>negative effect on beta glucans.

However, I calculate that with the 12 inch diameter mash tun I have, the mixer
would have to exceed 188 rpm to reach 3 meters/second tip speed.  That sounds
pretty fast and I don't think I exceeded that.

That leaves Hubert's reasons of aeration of the mash.  It sounds like aeration
due to the mixing may have been my problem since I did have large amounts of
teig as he predicted.  It sounds like this may be more of a problem than
shearing since we are not likely to exceed the 188 rpm or 3 meters/second
limits.  Except that the main reason presented for keeping tip speed below
3 meters/second was to prevent HSA.  If it prevents HSA, how could I be
getting mash aeration? They sound like they would go hand in hand.

I am still puzzled but don't intend to return to my auto-mixer.


John Wilkinson - Grapevine, Texas - jwilkins at wss.dsccc.com
 
 

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Date: Thu, 15 Jan 1998 15:30:35 -0500
From: AJ <ajdel at mindspring.com>
Subject: Diacetyl Question/Stir Bars

George dePiro wrote concerning diacetyl production in the package.
Conversion of AAL to diacetyl requires the presence of an oxidizing
agent in the beer (and molecular oxygen will certainly serve). As a
properly handled bottled beer presumably has virtually no dissolved
oxygen and contains melanoidins in the reduced state what would be the
oxidizing agent?

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* * * * *

Jeff Renner asked about stir bars "grinding up" yeast in starters. I
suppose anything is possible but most stir bars are shaped somewhat like

              _____n_____
             (                      )
              -------u--------

i.e. there is a ridge around the middle and the only place the bar
actually touches the bottom of the flask is on that ridge (bottom of the
"u" in the sketch) i.e. a relatively small area. I imagine anything
which gets trapped under that ridge gets squished but as the bar tends
to stay in place I wouldn't think that very many cells would get under
it to be pureed. The function of the stirrer is, after all, to keep the
cells in suspension.

Also, yeast cells have cell walls and are pretty hardy, at least by
comparison to animal cells. If you look in a lab supply catalog (e.g.
Cole-Parmer) under "Fermenters" you'll see that the gear for handling
cells like yeast cells subjects them to lots more shear force than the
gear for mammalian cells. By the way, one of these systems looks like
the way to make small starters. Temperatures are controlled as are pH
and DO level. The system even dumps in anti foaming agents as required
and the stirrers are suspended. Anyone with about $25K spare change can
avail himself of one of these nifty setups.


Return to table of contents


Date: Thu, 15 Jan 1998 15:50:04 -0500
From: "Houseman, David L" <David.Houseman at unisys.com>
Subject: Re:Subject: Air Space in Bottles; Blue Moon/Celis/Hoegaarden Whit

Charles said: "...A couple weeks ago I opened a bottle that
had been at the end of a batch when I bottled, and had been sealed only
half
full.  It was the first bottle from that batch that I opened...."

If like me the last bit from the bottling bucket goes into a bottle,
even if half full and to get it in I have to use something other than
the normal bottle filler, then I'd suspect an infection rather due the
process rather the air space in the bottle having any impact on the
carbonation level (ie gusher).  I've opened many a half full bottle and
not had any different level of carbonation than I have in the full
bottles.  In fact if anything, just the opposite since I open and drink
the odd bottles first just to keep an eye on carbonation levels and
often over time get more carbonation in the remaining bottles than the
1/2 full ones.

Dave Houseman
PA Suburbs of Philadelpia (USA not Greece)  

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Date: Thu, 15 Jan 1998 15:56:24 -0500
From: "Houseman, David L" <David.Houseman at unisys.com>
Subject: Subject: Re: Blade Shearing / HSA

Someone posted the other day that the over use of RIMS contributed to
excess lipid extraction.  Could it be that the shearing caused by pump
blades turning at very high rates might be a cause?  Perhaps Rob and
George and find out while at Seibel what experience there is in the
production of very "soapy" tasting beers which I suspect comes from
excess tannin and lipid extraction.  Could there be another source than
grain crush, sparge water temperature and mash runoff pH?

Dave Houseman
still in suburban Southeastern PA 

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Date: Thu, 15 Jan 1998 15:17:40 -0700
From: hmbrewer at juno.com (Jeff Foley)
Subject: Brewpubs NJ/NY

I will be traveling to Northern NJ and was wondering if anybody knew of
any brew pubs I could visit.


Jeff Foley
Sierra Vista, AZ
Thunder Mountain Brewery (One can wish can't they).

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Date: Thu, 15 Jan 98 17:23:16 -0500
From: dajohnson at mail.biosis.org
Subject: Nightmare


     
     Man oh man, for awhile there i was having this totally bogus nightmare 
     where i kept trying to log-on and check out the HBD, but everytime i 
     did the only thing I was getting was the BLEACH chemistry-Jack 
     Schmidling-bashing-Annheiser-Busch-hating-Alcoholics-Anonymous Digest. 
      That was really frightful.
     
     Cheers,
     
     dan



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Date: Thu, 15 Jan 1998 17:42:04 -0400
From: "David L. Thomson" <dlt at ici.net>
Subject: Re: Newbe step mashing

Hi, I am thinking of doning a hefe Weissen all grain batch next. Most
recipies call for step mashing. I have a Igloo 10 gal cooler mash tun.
Has anyone done such a thing?  My concern is that i am still recoving
from the Saprge from Hell!  I was stiring every 20 min of my infusion
mash.....No I dont know what I was thinking!! Anywho, won't I have to
stir when I add boiling water. Will this pack my Grist??
Any help would be appreciated!
Dave

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Date: Thu, 15 Jan 1998 20:50:49 -0600 (CST)
From: Paul Henning <phenning at cs.uiowa.edu>
Subject: 1997 Bitter Mania Results?


I was wondering if anyone had gotten any judging sheets back from the
Bitter Mania AHA Club-Only contest, held at the beginning of
December.  The usually helpful AHA administrator Brian Rezac has been
been rather unresponsive on this issue...

Cheers,
Paul Henning			Iowa City, IA

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Date: Thu, 15 Jan 1998 19:45:20 -0800
From: M Gates <mearle at orcalink.com>
Subject: Re: Magnetic Stirring, Copper bottom, Fuller's clone

Fellow Brewers:

Call me a gadget freak, but damn, this is remarkable. I built my own
stirrer from a cow magnet from a farm supply store, a 9VDC motor, a 300u
ohm rheostat, a recycled power transformer from an old modem, and a
teflon coated stir bar from Fisher scientific. All were assembled and
mounted in a custom made plexiglass box using hot glue with a section of
2X4 inside securing the motor. It works! 1st use: stirring my yeast
starter in a 1 liter erlenmeyer flask. A slow start engages the 2
magnets and away it goes. 
I did not figure a deep whirlpool effect was entirely necessary so I ran
it at just fast enough to stir - that's all. No yeast settling occurred.
The Scottish Ale starter took off rapidly, but the downside was
enthusiastic foam buildup and blowoff. That is the trouble with a flask;
the foam builds up into a more and more confined space. A few bubbler
cleanings later, about 1 1/2 days, I pitched the yeast into my 2 carboys
(a 10 gal batch). Unintentionally I poured the stir magnet into the
second carboy. Grrrr. OK, why not take advantage of it. I put the one
carboy on the stirrer (gingerly) and turned it on. Nothing happened. The
magnet in the carboy was in the gutter of the carboy. Funny, I had never
noticed that concave bottom before. After some awkward lifting and
shifting of the carboy to get the 2 magnets engaged I finally got the
stirrer operating. Wow! No whirlpool this time, but very pronounced
motion of the particulate matter (yeast/trub). So I have a control
carboy with no stirring and one actively being stirred. I don't even
have to tell you which one is fermenting faster do I? But I have a
blow-off problem in the second one again. Well that's the price you pay
for a fast ferment. It's almost finished now and the 1st one is still
bubbling slowly along. Both at 62F by the way. I will keep you posted,
but I honestly cannot see much downside to this stirring. Stagnant
conditions vs active nutrient mixing. Especially at the low ale
fermentation temperatures which I prefer, this seems like just the
ticket.

P.S The new copper bottom on my mash tun works great. Not a trace of
scorching. See the October/November Brewing Techniques magazine for info
on this. Tip: you need a very very good welder and need to be willing to
grind the weld down smooth yourself afterward. No one will touch this
kind of difficult welding otherwise.

Another Note: It's been 2 weeks now and my attempted yeast starter from
the sediment in a bottle of Fuller's 1845 bottle conditioned ale is a
failure. No activity at all. zip. Nada. Not one lousy bubble! My attempt
at cloning a Fuller's ESB clone goes ahead on schedule this weekend
anyway. One yeast will be Wyeast London III and the other the White Labs
E. Coast American Ale Yeast. Why these 2 yeasts? Because both have been
described as having the "nutty" taste that I liked so much in Fuller's
ESB. For good measure I am using Mild Ale Malt and last but not least
wild rice. 

Mearle

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Date: Thu, 15 Jan 1998 23:23:35 -0500
From: Margie and Dave Ludwig <dludwig at eagle1.eaglenet.com>
Subject: Chiller design and keg conversion

>
>I tried winding  the tubing into tight spirals but I still have about 30
feet of
>tubing left over.  I have never seen a planispiral chiller and I am not
sure if
>the coils should be overlapping or 1 single layer of coils.  I want to tie it
>together with copper wire to make it sturdy and easy to clean.  If you have
>suggestions, please pass them along.  
>
>Since this design is more efficient, maybe I need less tubing?

I don't have any experience with a planispiral chillers but I wouldn't
think it more efficient in terms of heat transfer efficiency. The thing
that helps the stacked coil is the induced free convection. So even if you
don't stir, there is a vertical flow across the coils that aids heat
transfer. I guess if the planispiral coil was loose (space between the
tubes), there would be a similar benefit but it seems like circulation in
the kettle would be hindered assuming the coil diameter was close to the
diameter of the kettle. Given the same length of tubing, I'd opt for the
stacked coil assuming your selection criteria is best heat tranfer
capability. 

On another subject, I just cut the top out of a 1/2 barrel keg with a Sears
Scroll saw and used one 36 tpi B&D pirahna blade. Being a somewhat serious
wood worker, I like to use jigs to get consistent accuracy and minimize
goofs. I took a piece of 1/4 inch plywood and cut a hole large enough to
fit over the center tap. Removed the saw base plate and attached the saw to
the plywood. The scroll saw blade can be oriented 90 deg from normal
direction so that's how I set the blade. The jig made sawing a near perfect
circle easy and stabilized the saw during the process. The blade does get
hot, as reported in other posts. I went about 2 inches at a time and rested
a few minutes (little bit of beer) between cuts. WD40 in between. Used duct
tape and taped over the cut as I went along. This prevented the top from
moving around too much and prevented it from falling into the keg during
the last bit of cutting. 

Dave Ludwig
Southern MD Brew


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Date: Thu, 15 Jan 1998 23:36:51 EST
From: AllDey <AllDey at aol.com>
Subject: Faucet cleaning

Brewing Collective,

I've finally knocked a major item off my brewery "to do" list: I got a single
shank, dual faucet "tap" coming through the side of one of my beer fridges.
Yippee!  After a week of enjoying the novelty of beer on tap without opening
the door, however, I've noticed that the handle on the faucet I've been
pulling pils from kinda sticks 'cause there's some dried crud in there.
What's the appropriate corrective action?  A shot of iodophor spray after an
evening of use?  Also, should I dissassemble and clean the whole faucet(s)
after finishing each keg.  My friendly beer distributor/homebrew owner (ain't
that ironic) recommends just running beer line cleaner through everything with
a short soak in the lines once a month (approximately every keg).
What think?

Thanks in advance!
Paul, Cheyenne WY

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Date: Thu, 15 Jan 1998 14:45:07 -0800
From: Kyle Druey <druey at ibm.net>
Subject: Protein Rest Quiz

Protein Rest Quiz
 
To protein rest or not to protein rest, who knows?  All we are told is
that the type of malt and the degree of modification determines if a
protein rest is needed.  I thought it would be interesting to present
modification data on 4 different malts and ask the experts to offer
their recommendations for a protein rest.  I pulled the malt data below
from the 1997 BT Market Guide:
 
No.  Malt                     %FG/CG    %SNR
- ---  ----                     ------    ----
1    Baird British Pale Ale   no data   41-44
2    Durst Pils               1.0-2.0   no data
3    De Wolf Pilsen           2.0       no data
4    Baird Premium Pilsen     no data   38-42
 
Noonan's article in the BT Market Guide offers the following
interpretations for the data above:
 
%FG/CG:  Stealy or vitreous malt has a value of 1.8-2.2% and is suitable
only for a mash that includes a protein rest.  Mealy/well-modified malt
has a value of 0.5-1.0% and is suitable for infusion mashing.
%SNR (Kolbach Index):  36-42% indicates malts suitable for infusion
mashing, over 45% the beer will be thin in body and mouthfeel.  For
lager malts 30-33% indicates undermodification, and 37-40% indicates
overmodification.
 
I am no mashing enzyme expert, and I wouldn't know a peptidase if it
walked up and smacked me up side the head, but I will make a guess at
it:
 
1) Hugh Baird Pale Ale, 41-44 %SNR: There is no question that this malt
is highly/well modified and suitable for a single infusion mash without
a
protein rest.  I think a good homebrewing definition of highly/well
modified is any malt that does not need a protein rest.
 
2) Durst Pils, 1.0-2.0 %FG/CG:  From what I can tell this malt is
in-between Noonan's guidelines and is probably moderately modified.  I
would use a protein rest of 20'  at  131F.
 
3) De Wolf Pilsen, 2.0 %FG/CG:  This malt is borderline undermodified
and
could use a 20' rest at 122F.
 
4) Baird Premium Pilsen, 38-42 %SNR:  Using Noonans guideline indicates
this malt is highly/well modified and does not need a protein rest.  But
how many pilsners are made without a protein rest?  Would you use this
malt to make a pilsner with a single infusion temp rest and no protein
rest?  I am not so sure so I would rest this malt at 135 F for 20'.
 
There was a good discussion last fall about protein rests.  Perhaps the
participants of that thread could take the quiz and anyone else who is
so
inclined.

Kyle Druey
Bakersfield, CA

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Date: Fri, 16 Jan 1998 10:13:47 +200
From: "Braam Greyling" <braam.greyling at azona.com>
Subject: The disadvantages of step mashing.

Hi 

Olin Schultz writes
>
> The disadvantages of step mashing.  The biggest is less head
> retention. This is more noticeable on lighter beers.  On high 
> gravity beers you get good head as a default of the higher 
> percentages of head stability constituents.  The other factor is 
> that step mashing provides for more exposure to the beta amylase set 
> of enzymes, which results in thinner beers.  This may or may not be 
> desired, but most homebrewers are

I tend to disagree. You cant say that step mashing causes all this. 
My step mash beers has got good head retention and I regularly brews 
a real thick beer when I want. 
Olin, are you sure you control your mash temps well  enough ?
This could cause your head retention problems.
When your mash-temps are well controlled I cannot see that you should 
have this problems with step mashing. 

Just a data point..
Braam Greyling    Design Engineer
Azona(Pty)Ltd     
tel +27 12 6641910  fax +27 12 6641393

You can taste a good beer with one sip, 
but it is better to make thoroughly sure.

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Date: Fri, 16 Jan 1998 07:57:58 -0500
From: Dave Bartz <gbrewer at iquest.net>
Subject: John Bull Wheat Syrup

Wayne_Kozun at otpp.com  asked:

>I am going to start a batch of an extract p-Lambic and I have obtained a
1.5kg can of unhopped John Bull Wheat Syrup.  Under ingredients it lists
Malt Extract, Wheat Extract, but it doesn't mention what proportion is
wheat and what proportion is barley malt.  Since malt is listed before
wheat I would assume it is less than 50% wheat.  Would anyone know what the
proportions are, or know how I can find out.  It doesn't appear as if the
John Bull company has a web site.<

John Bull's wheat liquid malt extract is 55% Wheat and 45% Barley.
Company literature says that the barley side is a "lager malt extract".

Dave Bartz
The Gourmet Brewer -"Beer is Good" 5000 BC
http://www.the-gourmet-brewer.com/   


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Date: Fri, 16 Jan 1998 23:12:52 +1000
From: Charlie Scandrett <merino at squirrel.com.au>
Subject: Practical Boundary Layers

Jim Bentsen posted in response to Kyle Druey:
Kyle Druey>In Charlie's informative post from yesterday he brings up some
KD>>design challenges associated with mash mixing and possibly RIMS:
CS>>The heat transfer problem is the formation of boundary layers and the
CS>>overheating of them. 

JB>>The boundary layer is a thin layer which forms between the blade and the
>fluid. I don't think that heat transfer in the boundary layer plays any part
>here as this would be TO or FROM the blade which would quickly reach the
>local temperature of the mash.

Boundary layers also form on the bottom of a mashmixed or static heated tun.
Only the shear points (points of max compression) are of interest in blade
laminar layers.

JB>> The purpose of mixing  the mash is to mechanically remove temperature
>differences by stirring. 

 But if there remains a static or laminar layer on the heated surface, it
overheats, causing enzyme, head protein damage and possible scorching. The
point of RIMS and mashmixing is to keep all heated surfaces turbulent AND to
promote mechanically assisted convection.

JB>>During mixing of a mash, the heat is transferred largely by conduction
>through the contact points of the grain and the 'mechanical" convection of
>the surrounding fluid due to the stirring action. 

Convection, mechanically or thermally induced, is far more important than
conduction, which is very slow in water, thus the problem with boundary layers.

CS>>The speed necessary for turbulent flow to prevent
>>these boundary layers is greater than the optimum for low oxidation and
>>shear degradation.

JB>Turbulent flow is, in the context used here, one of two forms of boundary
JB>layer flow   ( laminar being the other). It is a TYPE of boundary layer. It
JB>does not PREVENT a boundary layer. In fact turbulent boundary layers are
JB>actually thicker than laminar boundary layers

Yes, that is technically correct. Any layer near a boundary is a boundary
layer. The point is that when they become turbulent the "overall coefficient
of heat transfer" rises by approximately 10 times! The laminar boundary
layer ceases to become a *barrier* layer. This is the crucial practical
point, not the terminology. When the heat resistance drops to ~1/10 th, I
consider the problem "prevented".

KD>If the mixing is slowed enough to avoid a vortex and shearing, then
KD>perhaps now the flow is laminar producing boundary layers and uneven
KD>heating (the thermodynamicists out there please correct me if I am
KD>wrong). 

JB>Laminar boundary layers do not produce 'uneven' heating. They are just less
JB>efficient than a turbulent layer in moving heat to or from a solid wall, ie
JB>the heat transfer coefficient is lower in laminar flow.  If the vortex is
JB>weak enough so that poor mixing occurs, then the whole purpose for the
JB>blades is being defeated.

Laminar boundary layers *do* produce uneven heating. By raising the "overall
coefficient" of heat transfer by about 10 times, they cause a much steeper
temperature gradient from the hot wall &/or RIMS element to the centre of
the mash. Part of the mash(the laminar layer) will thus achieve temperatures
much higher than a turbulent mash, this is uneven and critical.
The turbulence is achieved rather suddenly, it can be calculated by esoteric
math involving Prantl and Renyolds numbers, however this is best left to
thermodynamic engineers, I used to struggle with it in a lab 25 years ago
and empirical results were always different. The practical tip speed limit
for mixing blades for problematic shear forces is about 2 metres per second.
I doubt this rotation speed will produce turbulent flow across the whole
bottom or even side of a mash tun.  This is why some manufacturers have the
blades so close to the heated surface so as to mechanicallly disturb laminar
flow when it cannot be disturbed by fluid velocity alone. 
However in a small tube like a RIMS, 2 metres per second would usually
produce turbulent flow, the diameter of flow influences the calculation. My
post@ the "Brewery" on turbulent flow in "chiller" coils is incorrect by
about 40%, I will redo those calculations.

KD>This may relate to mash mixing, but does it relate to RIMS?  Does the
KD>liquid part of the mash that is recirculated create the same shearing
KD>problems as with mixing? 

JB>No. With no blade moving, there is no mechanical surface to create
JB>significant  shear layers or vortices in the flow. 

Yes, with RIMS there is a pump. Considerable design has gone into wort pumps
to prevent this. Basically a pump with a radial type impeller is a no no.
The pumps with spiral type impellers are much better.

We are concerned with overall even temperature, this is achieved by good
convection. We are also concerned with localised critical overheating, this
is prevemted by achieving turbulent flow. Both solutions can be achieved
with both mashmixing and RIMS, I thought it was simple and that the problem
was design, not terminology.

Charlie (Brisbane, Australia)

PS David Hill asked about powering a heated mixing blade. I'm sorry I didn't
explain, slip ring type electrical connections are an off the shelf item in
industrial gadget suppliers. I forget that the rest of the population
doesn't keep a library of their catalogs. Ask a design engineer out of the
Yellow pages for a local source.


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Date: Fri, 16 Jan 1998 08:34:01 -0500
From: Glenn Raudins <raudins at ct.picker.com>
Subject: Siebel Short Course Textbooks

Mike Rose asks about the Siebel Short Course:
        1 What textbooks are you using?

Siebel produces two 3 ring binders for the course.  One binder for each
week of the course, consisting of sections for each lecture, beer
tasting, and Sensory Analysis lab.

        2 Are they avaiable to the public?

Yes, you can order them from Siebel for I believe $750.

        3 Do you recommend them?

Some portions of the books are designed to be used with the lectures and
other portions are designed to be read after the course.  Basicly, at
this price, I would just recommend going to the course as it is
fantastic! (As you have been hearing from Rob & George.)

Happy Graduation to Rob & George, you will miss those breaks between
classes with the great beers and diverse conversations.

Glenn 
Graduate of the 62nd Short Course

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Date: Fri, 16 Jan 1998 07:39:57 -0600
From: Randy Lee <rjlee at imation.com>
Subject: RE: Will any CO2 do?

> Frankly I've wondered the same thing. Just how clean is this CO2 that we
> buy? I'm not worrying about it, though. The regulator I bought had an

When I first got a CO2 setup, I went into the local supply and asked for
medical grade CO2. The guy asked me if I really wanted that and
explained that the welding CO2 and Medical CO2 came from the same tank,
only the paperwork was different. Sounds about right. It is (possible*
that the tanks are different, but somehow, I doubt it. If you get real
uptight about it, add an absolute inline filter

Randy Lee
Viking Brewing Company
Dallas, WI.

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Date: Fri, 16 Jan 1998 23:42:22 +1000
From: Charlie Scandrett <merino at squirrel.com.au>
Subject: O2 and Yeast (thread anyone?)

Ken Schwartz posted:
>  "Also, note that a properly pitched quantity of yeast will reduce the
>oxygen content of the wort to zero in 30 minutes (AJ DeLAnge-?)."

>I remember this comment as well (pretty sure it was AJ), and it's always
>bugged me in a way.  Why do we go through so much trouble oxygenating our >wort
>if the oxygen is consumed so quickly by the relatively small amount of yeast
>pitched?  And if the answer is "to build cell walls and stuff", then why not
>oxygenate your starter medium, allow it to sit for 30 minutes, then pitch >into
>a non-oxygenated main wort?  What's the difference?

This is similar to the "why don't we pitch enough yeast and not worry about
growth and aeration at all" argument. Without complex yeast metabolism
discursions, there are two important reasons:
1/ We need a younger demographic in our yeast population, i.e. a proportion
of new yeast. All oldies doesn't make a tasty party.
2/ We need to comsume the fatty acids that yeast use oxygen to synthesise
sterols for cell wall building. FANS too need to be comsumed by growth.
These compounds can cause head/flavour defects in higher concentrations and
are food for bacteria if the yeast don't get them first.

There is another undocumented reason not to aerate only starters and not
wort.(Andy Walsh put me on to this line of inquiry)Professional brewers will
tell you that continuously aerated propagation cultures will produce such
Estery beer in the first batch that is has to be blended to be sold.
Apparently yeast adapt to the high oxygen evironment and don't take kindly
to moving to a relatively lower O2 evironment. However they react favourably
in going from a low O2 starter to a high O2 fresh wort.

Charlie (Brisbane, Australia)


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Date: Fri, 16 Jan 1998 08:41:20 -0500
From: Glenn Raudins <raudins at ct.picker.com>
Subject: Zima Brewing

Gabi Scharfetter asks about brewing Zima:

Though many will argue about Zima's worth, process wise, it is an
interesting beverage.  For what I have heard (from a person who helped
with the Zima Project), the beverage is brewed as a beer then run
through carbon filtration (and possible some other steps) to remove any
indicator that it once was a beer (color and flavor).  After this, 
flavoring and compounds to prevent any head formation are added. 
Unfortunately, I can't offer any direction in making some at home.

Glenn

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Date: Fri, 16 Jan 1998 09:35:43 -0500
From: "Little, Wayne" <LittleW at od31.nidr.nih.gov>
Subject: O2 Again

Two O2 commentaries in the 1/16/98 HBD (George De Piro and Ken
Schwartz), highlight my confusion on this subject.  Do yeasts pitched
from a starter, sit in the wort and take up all the O2 in about 30
minutes, and then pass the O2 to the cell walls of only 3 generations of
progeny? This doesn't make sense. I don't oxygenate my wort (other than
pouring cooled wort into the fermenter) and I wind up with a lot of
yeast slurry in the bottom of the tank.  Aren't the  yeasts dividing
about every half hour, and isn't division occurring during fermentation
in the absence of oxygen. I understand that yeasts need some oxygen to
form sterols for cell walls.  Does all oxygen have to be in the form of
O2, or can it come from the metabolism of oxygen-containing molecules?
What does Siebel say on this?

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---