---

	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:
  RE: Keeping Warm (LaBorde, Ronald)
  Mixmasher (Jack Schmidling)
  Oven Mashing (Mark Riley)
  plastic buckets (AlannnnT)
  Re:Dubbel,Tripple (Rosalba e Massimo Faraggi)
  freezing Hops (Lizardhead)
  aerobic starters ("Hubert Hanghofer")
  Dry Ice  !!!!!!??? ("George A. Forsyth")
  Re: Keeping Warm (Ed Choromanski)
  Villainy and crass commercialism (Samuel Mize)
  Re: High Altitude Brewing Record ("Brian Rezac")
  Yeast Questions ("David Johnson")
  Blade Shearing / HSA (Kyle Druey)
  reverse osmosis. effectiveness? (Jon Bovard)
  Carbonation Question (LONF)
  Re: Corma and Historical Brewing Digest (Dan Cole)
  refractometer ("Norman L. Brewer")
  Late Addition ("Keith & JoAnn Zimmerman")
  Food Grade Plastics (Richard Byrnes)
  Infusion versus step mashing (Randy Lee)
  Food Grade HDPE (Tom Clark)
  Re: Lactic vs Phos acid (Joe Rolfe)
  Re: High Altitude Brewing Record (Spencer W Thomas)
  pooped yeast... (Lou Heavner)
  Mixmasher results (MacRae Kevin J)
  pH: when to measure/ chill haze/ boiling kettles (Adam Rich)


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Date: Wed, 7 Jan 1998 14:05:33 -0600
From: rlabor at lsumc.edu (LaBorde, Ronald)
Subject: RE: Keeping Warm

From: tonyw at Mass-USR.COM (Tony Willoughby)

>1)  What's the best source for heat?  A light bulb seems the obvious
solution,
>but I'm concerned about the effect of light on my brew. ....
>....what alternatives are there?

Before I was fortunate to get two freezers this is how I did it:

I placed the fermenter into a picnic cooler large enough to hold it,
filled up with water (not so much that the fermenter floats!),  and to
cool it,  placed 2 liter ice bottles as needed.   To heat when the
weather in LA changes (every second day),  I used the heat from a small
aquarium pump.  The pump uses several watts (power to run it from the AC
line).  It is a submersible pump around $25.00 from fish store.   The
pump moves the water to even out the temps,  and the small amount of
heat from the pump is enough to keep the temperature up.   

>2)  Thermostatic control.  Has anyone come up with a solution for
maintaining 
>an ale fermenting temperature?  A Honeywell home-furnace type
thermostat >would
>be ideal, but I don't know how one would switch a 120v line with the 6
volt
>thermostat.  (I'm no electrician, but I think I could follow simple
>directions.  :^) 

I used a wall heating/cooling thermostat meant for central units.  These
are made to work with 24 volts control voltage,  so I installed a small
24 vac transformer in a box with a 24 vac relay and used the thermostat
to control heat and cooling.  I had to manually switch from heat to cool
depending on what was needed.   The thermostat  must be the electronic
type with a thermistor sensing element.  Most newer thermostats are now
this type.   I removed the sensor and added 4 foot of wire and placed it
into 2 foot of vinyl tubing,  folded the tubing in the middle to make a
waterproof probe.

I got tired of juggling the ice bottles, so riged up a smaller cooler
for the ice water,  and used the pump and thermostat to circulate the
ice water.

Worked pretty well, and with my bedroom window cracked open, I could
hear the pump cycling in the backyard brewhouse.  Actually helps me go
off to sleep - sort of like hearing rain cures insomnia.

Ron

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


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Date: Wed, 07 Jan 1998 10:18:45 -0800
From: Jack Schmidling <arf at mc.net>
Subject: Mixmasher

From: Charlie Scandrett <merino at squirrel.com.au>
Subject: Jack has invented an ANAGRAM(R)!!

You got it.  I looked at an old ringer wash machine, made few
a minor changes, put it all in caps, added (R) and the MALTMILL(R) 
was  born.

BTW, the (R) has nothing to do with invention.  It is a trademark
registration.  If someone wishes to sell these things, they have
to call it something else or at least use lower case letters (I
didn't invent them either).

Did the same thing with a Kitchen Aid and false bottom  I won't
bore you with the details but there is also an EASYTESTER(R) for
telescope nuts.

"It wasn't overlooked, I have seem over a hundred in commercial and
homebreweries....

I believe I was referring to the homebrew community.

"For example, Jack turns the heat off at the target temperature and 
continues to mechanically stir an uninsulated metal vessel. 
When he turns it on again about 30 minutes later (half time at the 
footy?) the temperature has dropped considerably.(I know it doesn't 
happen to you Jack, but elsewhere, the laws of thermodynamics apply)
This is a problem for homebrewers because we usually can't build direct 
fired vessels that are well insulated.

On the other hand, as we are only making relatively small batches,
the real cost of the heat loss using an un-insulated is not worth
considering.  My simplified explanation of how it can be used is
not necessarily the way I acutally use it anymore than the 
instructions shipped with an EM are the way I brew beer.

In actual practice, I do not necessarily shut off the heat.  I know
the system will enough by now to be able to set the flame at a level
that just compensates for heat loss.

" You could get the same result by bending the blades more like a 
ship's propeller and running at half the speed. 

That $30, 3" one I mentioned was precisely that.  Ever price a
12" ship's propeller?  The fan blade is a usable alternative that
is practically free and off the shelf.

"Mash Mixing needs insulation and automatic control of the heat source to
approach the accuracy of RIMS in the homebrew environment.....

But again I ask, can you taste that .01 degree accuracy?

"What torque is necessary? Well, a washing machine runs at least twice as
fast(4 times power load) with twice the volume (two times power load)on a
1/4 hp motor. Using a 1/16 hp would be plenty.

Glad you asked....

I found the ID of the motor I used so I could look up the specs in
the Granger catalog.  I will add it to the web page when I get to
it.  As I said before, if I did it over I would get a larger one and
it need not be reversable.

Granger # 2Z814
RPM: 30
Torque: 10 in/lb
HP: 1/100
110vac at .3a
Price: $47 plus capacitor.

"PS I agree with Jacks "greedy lawyers" comment. Ever tried getting a
pressure vessel certified? It is basically an unfused bomb....

In this country anything with a line cord is basically an
electric chair looking for a victim.


- -- 
Visit our WEB pages: 
                        Beer Stuff.........http://ays.net/jsp
                        Astronomy.......http://user.mc.net/arf
             ASTROPHOTO OF THE WEEK..... New Every Monday



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Date: Wed, 7 Jan 1998 12:45:16 -0800
From: Mark Riley <mriley at netcom.com>
Subject: Oven Mashing

All this talk about RIMS and MIXMASHING/MASHMIXING/MISHMASHING
prompts me to describe what I do and that is OVENMASHING(R).  ;-)

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.  The thermostat in my oven allows me
to set it to very low temperatures (I suspect not all ovens
are capable of this, though).  Since the ambient temperature
in the oven is nominally the same as the mash, insulation
isn't an issue.  I do, however, check in on it every 15 minutes
and give it a stir since I feel some stirring is necessary to
make more starch and/or protiens available to the enzymes (can
anyone comment on this?)

Of course I didn't "invent" this technique, I'm just mentioning
it here since there's been talk about "simple" and "low cost"
mashing systems.  I think it qualifies for both.

Mark Riley
The Beer Recipator - http://realbeer.com/brewery/recipator

P.S. (USA only) Don't you actually have to *sell* something across
state lines in order to trademark it?


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Date: Wed, 7 Jan 1998 16:28:54 EST
From: AlannnnT <AlannnnT at aol.com>
Subject: plastic buckets

White food grade plastic buckets are available for free or almost free many
places. [Homebrew bribes may have to be paid].

Dunkin' Donuts and other bakeries and donut shops use millions, literally.
They throw them out, or give them away when used once. [around here they give
them to commercial fisherman for free or almost free]

The potato[e] salad and cole slaw at your grocery store or deli comes in the
same.
[add the letter e to potato if you have political aspirations.]

Food flavors and extracts come in these buckets. Look in the yellow pages for
commercial producers and users of extracts. School cafeterias use them alot.
Peanut butter, mayonaisse, fruit concentrates, pickles, salads, etc., all come
this way.

It is best to leave them out in the sun awhile or soak them in mild bleach
[let's not start that thread again], bleach works fine. The fruit flavors used
at dunkin donuts are very tenacious, clean the buckets well! 

In my buisness we sell hundreds of these recycled buckets, and we don't pay
more than the cost of picking them up and cleaning them out.

Best Brewing
Alan Talman

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Date: Wed, 07 Jan 1998 23:02:26 -0800
From: Rosalba e Massimo Faraggi <rosamax at split.it>
Subject: Re:Dubbel,Tripple

>I am looking for some enlightenment for the terms single, double,
>triple,etc.. 
 ...
>I have heard 2 explanations on this
>1) the terms relate to strength X, XX, XXX... but this does not explain the
>fact that double is dark and triple is very pale but stronger
>2) the  terms indicate the number of fermentations included in the process.. 

I think 1) is right. Probably a few breweries called their beers in this
way, but it is the Westmalle Trappist brewery that produced (and is
producing) the two most famous and outstanding examples of beer with
these names: a dark, malty but dry double and the strong pale triple.
Many other breweries then started to imitate these beers (expecially the
triple), so Westmalle set the prototype of these styles.
"Triple fermentation" is a term that is sometime applied to some belgian
beers (if I remember Orval, maybe Westmalle itself?) but I think it just
means a normal primary fermentation, a further maturation - perhaps with
another yeast addition - and then the bottle conditioning. Correct me if
I am wrong.

Massimo Faraggi
Genova ITALY - don't know the miles from Westmalle, but surely closer to
it than Jeff Renner!

http://www.split.it/users/rosamax/   my beer page!
Currently 10 doubles and 23 triples in the database of tasted beers.

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Date: Wed, 7 Jan 98 15:30:07 -0700
From: Lizardhead <memerson at fone.net>
Subject: freezing Hops

Greg is wondering about freezing hops.

> I was wondering 
>if I could do more to save the aromatics. What's the lowest temperature 
>that they'll take?

Cold storage is of course the best way to retain freshness and prevent 
oxidation of alpha acids.  Commercial Hop merchants (Hop Union, Steiner, 
etc.) store their hops in bales at 26 - 31 degrees.  Mostly on the lower 
end.  Check out the temp on your freezer, it's probably pretty close to 
this range.  Lower temperatures may make whole hop flowers (water content 
approx 8%)  shatter more easily, but the lower water content of pellets 
make them far less suseptable to any freezing damage.

Mark Youngquist

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Date: Thu, 8 Jan 1998 00:48:13 +0200
From: "Hubert Hanghofer" <hhanghof at netbeer.co.at>
Subject: aerobic starters

In HBD#2603 Charles Rich posted a nice article on easier sterile wort 
oxygenation for starters. I'll take the opportunity to share some of 
my experiences. I wasn't able to read the December issues of the 
HBD yet, so I apologize if this has been addressed already in the 
thread on "starters and pitching rate" (...and for being behind 
schedule...).

Aeration / oxygenation is with no doubt a critical step in many 
brewing systems. Unlike beer, wort with all its unspent nutrients and 
the high pH is not a very selective medium - a wide variety of 
microorganisms can get a foothold and if this happens already in the 
starter...

The safest way for me to keep starters sterile and - in the same 
way - maximize yeast performance, is to leave the aeration 
/ oxygenation step but use conventional *aerobic culturing* instead 
 - that is: maintainig a small amount of oxygen in the starter 
culture, usually done in an erlenmeyer flask that's sealed with 
a ball of cotton wool and shaken continuously on an expensive 
Lab-machine.

The thread on starters gave me a great idea in doing so at home: 
magnetic stirring! 

I prepare 500mL (1 pint) of P6-8 (SG 1.020-1.030) starter wort in a 
1000mL erlenmeyer, add a magnetic stirrer (4cm =3D 1.55" teflon coated) 
cover it with an inverted glass-cup, boil for 15 minutes and cool. 
I use a small camping burner for boiling - lab grade glassware 
(Duran, Schott) won't burst. Keeping the glass in place on top all 
the time - everything is hermetic so far.

 ...But now the invaders get their chance for 5 seconds or so - need I 
worry? -I remove the glass beaker, add the yeast, and seal with the 
cotton ball.

I've done aerobic culturing before but I only made 4 starters with 
magnetic stirring so far. I applied 3 inoculation methods however and 
all gave the same results:

1) blown Wyeast package W2278, W3333
2) Yeast from the surface of a slant (local wheat variety), suspended 
using a few mL of sterile water (filtered <0.2um, using a Sartorius 
Minisart syringe filter).
3) 3 inoculation loops full of plated yeast (local lager strain -
from the bottle of a delicious unfiltered "Stiegl Paracelsus").

I always stirr at 250-350 rpm, the vortex didn't trap in air 
bubbles. The stirred starter cultures are kept at 20C (68F) and never 
show any foam. Within one day the starters get turbid. When I stop 
stirring, they flocculate and show some CO2 , but I get the maximum 
of yeast on the second day - yeast flakes become visible during 
stirring and when I stop it, I get +50mL of sediment. The lager 
starters were droped to 15C on this 2nd day. The aroma of aerobic 
cultures is somehow strange, I'd describe it as sour (no infection, 
just other metabolics, I keep an eye on my partner with my 
microscope).

 -So 2nd day is brew day and I step up to 800-1000mL (1 quart) with 
P12 (SG 1.048) wort made from first runnings (diluted, boiled and 
chilled - using another erlenmeyer). This is just 3-4 hours before 
pitching but it's the final push for the yeast. The vortex collapses 
(need to order that 2000mL Erlenmeyer soon) and the yeast begins to 
foam. I pitched 50L so the pitching rate with this final starter 
volume was 1:50 in every case. The lag time (first signs of foam) of 
the ales (pitched and fermented at 20-22C) was <10hrs, the lagers 
were pitched at 16C and put in a 12C basement ...sorry, fall asleep 
during watching for the lag time but must have been <16hrs.

I should mention that the whole process from striking the plate with 
the Paracelsus yeast until pitching the batch was exactly 7 days
 ...7 days of healthy aerobic conditions for the yeast!

I used open fermentation for the wheat, an air locked HDPE cask for 
the lagers, bottled green after one week, aged warm (18-20C) for 
another 5-7 days to allow the yeast to clean up the fermentation by 
products, then crash cooled to 0C for another week.

BTW, when harvesting the yeast and cleaning the fermenter, don't 
forget to remove that magnetic stirrer, that has slipped out of the 
erlenmeyer and dropped into the wort when you pitched the starter ;)

1 lager and 1 wheat has already been evaluated and found to be very 
clean. But we were particularly impressed by the microscopic 
exploration and evaluation of the bottle sediment. It was very clean, 
even after treatment with 5%KOH to remove protein, I hardly could 
find my enemy. When abusing anaerobic (air-locked) starters by not 
stepping up and underpitching at a rate of 1:50 I usually got lag 
times >16hrs and saw some invaders among my beloved yeasties. - Some 
rods of lactic bacteria with open fermentation while the strictly 
anaerobic coccus bacteria mainly count in closed fermented beers. 
Their count was far below any level that would affect flavor or 
aroma, but they *are* there ...staring at me through the microscope, 
telling me: "hey brewboy, next time we beat you and you better drink 
this one soon..."

Yeast loves aerobic conditions, the process of anaerobic fermentation 
is stress for them but yeasts are perfect machines: if well prepared 
for their big job, nothing can stop them anymore.

*****
Provide a healthy yeast population that's vital and ready for 
defence: _keep your starter culture aerobic until at least 50% 
attenuation has been reached_!
*****

 ...If you can't purchase pre-packed cotton

Sterilizing cotton wool:

1) The crude method:
 -seen and practised in the lab of a Bavarian wheat brewery. Ignit it 
and seal the Erlenmeyer flask with the burning cotton! Take care of 
your fingers and your brewery.

2) The secure method:
I pack my portions in SelfSeal ViewPacks by Lawson Mardon (U.K.) Ltd. 
Those sealed packs can be sterilized with steam (autoclave) or 
Ethylenoxide and usually are used to pack medical tools for 
sterilization and keeping them sterile during storage.

Source for cheap magnetic stirrers:

Read the article on building one by John Schnupp in HBD#2570


CHEERS &
sehr zum Wohle!
Hubert in Salzburg, Austria
http://www.netbeer.co.at/beer/

BTW, I re-pitched all my magnetic stirrers, anyone a good and cheap 
resource?

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Date: Wed, 07 Jan 1998 17:52:52 -0600
From: "George A. Forsyth" <gforse at nevia.net>
Subject: Dry Ice  !!!!!!???

Okay, after lurking off and on for several years, my first post. 	

I am a novice brewer for some time.  I do primarily "kit beers", ales
with single stage fermentation and simple equipment which has satisfied
my tastes for some time.  Eventually, I may branch out, but for now,
that is where I am.	
	
My question concerns a practice which a friend of mine swears by. He
lets the fermentation of whatever he is brewing (none of which I've
actually sampled) go until completed, (no SG readings) and charges his
brew by adding a small piece of dry ice (!) to each bottle immediately
before capping.  Has anyone heard of such a thing? I think it sounds
dangerous and irresponsible. 

Also he would like to find a filter medium which would filter dead and
live yeast out of his beer.  Does such a medium exist? I would think
anything that fine would take impossibly long to filter because of the
small pore size.

Comments??


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Date: Wed, 07 Jan 1998 13:03:48 +0000
From: Ed Choromanski <choroman at voicenet.com>
Subject: Re: Keeping Warm

Tony:

I do not have a basement or a location where I can put a fermenter and
have constent temperature (let alone the right temp).  I have recently
solved this problem for the cool brewing season.  I went to Walmart and
purchased a trash can big enough to hold my 6.5 gal primary.  I fill
this up with water halfway up the carboy.  Then I lower into the water a
fish tank heater, a 50 watt heater should be fine (which was previously
set to the desired temp in a bucket of water).  Depending on the ambient
temp, this may be all that you need, I wrap the trash can with
insulation I had laying around.  Have done this with 2 batches so far
and works great.

Happy Brewing,
Ed

Date: Tue, 6 Jan 1998 06:30:31 -0500 (EST)
From: tonyw at Mass-USR.COM (Tony Willoughby)
Subject: Keeping Warm

I've got two problems that prevent me from fully enjoying brewing...
Maintaining a consistent temperature of my primaries and secondaries...

1)  What's the best source for heat?

2) Thermostatic control.

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Date: Wed, 7 Jan 1998 17:56:10 -0600 (CST)
From: Samuel Mize <smize at prime.imagin.net>
Subject: Villainy and crass commercialism

Greetings to all.

I keep hearing these wild accusations about Jack Schmidling.  So I
reviewed his 1997.  For an analysis, email me.

Best,
Sam Mize
- -- 
Samuel Mize -- smize at imagin.net -- Team Ada
Fight Spam - see http://www.cauce.org/


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Date: Wed, 7 Jan 1998 18:20:27 -0700
From: "Brian Rezac" <brian at aob.org>
Subject: Re: High Altitude Brewing Record

In Reference to:
> > On August 30, 1997, 8 members of the Tribe Homebrew Club of Longmont,
> > Colorado brewed a batch of beer on Colorado's highest peak, Mt Elbert
> > (elev. 14,433 ft.) in an endeavor they termed OPERATION: Hypoxia.

Scott Kaczorowski wrote:
> I apologize for the complete lack of content, but:  :-)  Are there
> pictures?  What a worthy endeavor!

We do have photos!  They're on the web at the Tribe's homepage at:  
http://www.geocities.com/NapaValley/4003/

At the homepage scroll down and click on "OPERATION: Hypoxia".  Once there
be sure to view the other photos by clicking on "MORE" at the bottom of the
page.
 
> A question about Mt. Elbert:  What's the delta el and distance?  For Mt.
> Whitney (14,495ft), it's something like 6,100ft of elevation from the
> trailhead to the top with 14 (11?) miles of trail.  It takes all but the
> strongest backpackers two days to get all the way up.  OTOH, the water
> could be pumped at Trail Camp, at about 11,500ft (?).  Hmm...Anybody want
> to coordinate something like this with me?

If my memory serves me, the trailhead's elevation was 10,050 ft. and the
peak of Mt. Elbert is 14,433 ft.  So the difference is about 4,400 ft.  It
was a distance of about 4.5 miles.  I was among the last of the commandos
to get to the top and it took me 6 hours.  (I was a water bearer...I have
two bad knees...I had a rock in my shoe... I can post more excuses later as
I think of them.)  We were up and down all in one day, but we started at
dawn and finished after dark.

> Also:  Can it be an extract batch?  I think all-grain would have a higher
> niftyness factor, but obviously extra equipment and water.  I say:  AG
> Imperial Stout.  Lessee...we're gonna need a half dozen Whisperlites,
<snip>
> ...and complete lack of regard for what this whole thing might actually
entail.

We brewed a dry malt extract based barleywine.  Once your on the trail, the
"higher niftyness factor" diminishes considerably.  I'm sure that once you
committ to attempt Mt. Whitney, the Tribe members would be happy to share
their aquired equipment knowledge.  (We did a little trick with the
burner.)

> Honestly, any CA backpacking homebrewers want to take a run at this in
> the late Summer? ...<snip>... success is not assured, but worth a shot,
no?
> 
> Scott Kaczorowski
> Long Beach, CA
> kacz at nfs.aisf.com
 
Sincerely, Good Luck!  Keep me updated on your progress and let me know if
there's anyway the AHA can help you.

 -  Brian

Brian Rezac
Administrator
American Homebrewers Association  (303) 447-0816  x 121   (voice)
736 Pearl Street                               (303) 447-2825   (fax)
Boulder, CO  80302                           brian at aob.org   (e-mail)
U.S.A.                                             http://beertown.org 
(web)


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Date: Wed, 7 Jan 1998 20:48:23 -0600
From: "David Johnson" <dmjalj at inwave.com>
Subject: Yeast Questions

Brewers,
    I obtained a quart of yeast slurry from a local lager brewery. I was
given a quart of slurry the brewer said that it had 85% yeast and that was
90% viable as he had checked it that morning. He also made a comment about
the maximum pitching rate and said when he does a maximum fermentation he
uses 32 gm. of dry yeast in 200 ml. wort. He said that is maximum
fermentation and any more yeast would be too much. He suggested that I stay
below that and probably about half. Well I calculate that for a 5 (US) gal
the max (as he figures) would be about 3 kg or 6.6 lbs. My quart of yeast
slurry weighed about 1 kg or 2.2 lbs. There does not seem to be much
settling and almost all of that seems to be yeast. So I am ready for this
weekends CAP.

Do I need to do anything special to get this ready to put on slant or can I
just get a loopful and spread it on?

Dave in Monroe, WI


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Date: Wed, 07 Jan 1998 22:13:47 -0800
From: Kyle Druey <druey at ibm.net>
Subject: Blade Shearing / HSA

 -Blade Shearing

In Charlie Scandrett's informative post from yesterday he brings up some
design challenges associated with mash mixing and possibly RIMS:
>The heat transfer problem is the formation of boundary layers and the
>overheating of them. The speed necessary for turbulent flow to prevent
>these boundary layers is greater than the optimum for low oxidation and
>shear degradation.

Here is a reference on shear degradation (Fix, "An Analysis of Brewing
Techniques", p 25):
"Of particular relevance to mashing is the need to avoid shearing forces
created by excess stirring, as they have negative impact on enzymatic
activity."

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

Here is a reference which relates to temperature gradients in the mash
(Fix, same, p. 26):
"In some mashing systems, precise temperature control is problematic,
which creates a situation where two or more temperature regimes may
coexist in the mash at a given rest.  In such circumstances, yields,
RDFs, and other data can vary in erratic and unpredictable ways."

This may relate to mash mixing, but does it relate to RIMS?  Does the
liquid part of the mash that is recirculated create the same shearing
problems as with mixing?  Charlie also indicated that some professionals
believed that RIMS was problematic to the stability of the finished
beer. I am not sure what that means, but I would like to know and
compare this information with my RIMS beers.  I am not doubting him, I
just have never heard this :>).  If this shearing is problematic with
RIMS, perhaps the solution is to minimize flow during temp rests, and
only run at high flow during temp boosts.

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

 -HSA

Jack S on HSA during mashing:

>Like so many other buzzwords, HSA makes great raw material for
>articles and books but I am skeptical as to how it applies to the
>relatively slow movement and temperatures we deal with during mash.

I was able to find one reference on HSA: 

"We also can control the amount of oxygen uptake and the amount of
hot-side abuse that takes place during mashing.  The evidence
documenting the negative effects of hot-side aeration is extensive." 
(Fix, same, p 25)

This can lead to the following problems:

*Off Flavors*
>Oxidation (HSA)is caused by any formation of a vortex or any folding
>turbulence that includes air. The test for this is simply to observe
>the motion. Shear forces form whenever an agitator blade moves faster
>than the fluid can flow past. These forces can squash and degrade large
>complex molecules, causing flavour problems. I believe much of the
>"sewer/ onion"" aroma of Australian industrial beers is caused by the
>willy nilly use of centrifuges in the relentless search of cheaper,
>faster beer.
(This was from Charlie Scandrett's post, I know what I have read
supports his statements, but I would like to see some references.)

*Limited Protein Degradation*
"It was once believed that the traditional protein rest was of limited
value, and data were presented to support this conclusion.  This was in
direct conflict with other data that showed there was significant
proteolytic activity during rests at 113-140 F.  Hot-side aeration was
the key in resolving this conflict.  In a gentle low oxygen mashing
system, protein degradation does take place, but in a less favorable
environment, this may not be the case." (Fix, same, p. 25)

Perhaps the enzyme and mashing experts can offer explanations why this
would be a problem.  I am sure this info on protein rests will spark
some debate.  At the very least, it is important to design your RIMS or
blade mixing system to be a "gentle low oxygen mashing system".

Fix offers the following references on HSA:
Narziss, Brauwelt, 1993, #3
Huige, Beer and Wine Production, 1992
Fix, Zymurgy 15:5, 1992

It would be nice if someone who has these references could post some
info on HSA from them.  This would be good info for later referencing in
the HBD archives.  As Jack S pointed out, RIMS is subjected to HSA just
as is mix mashing.  With RIMS, the key is to ensure no air is entrained
on the suction side of the pump, and to design the wort return manifold
so that the exit velocity is slow enough to avoid wort foaming.  It can
be done very easily, look at the many web pages that have pictures of
the proper return manifold design.

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


Kyle Druey
Bakersfield, CA

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Date: Fri, 09 Jan 1987 04:09:53 +1100
From: Jon Bovard <j.bovard at student.qut.edu.au>
Subject: reverse osmosis. effectiveness?

My water weighs in at about 260-360 ppm dissoved solids. HARD HARD HARD.

My new reverse osmosis filter brings it down below 50ppm. Would you consider
this effective. Has/does anyone uses these, will it dramatically alter the
taste of my mashed beers. Afterall water constitutes 90% of beer?

cheers
JB in stagnant brisbane


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Date: Thu, 8 Jan 1998 02:19:44 EST
From: LONF <LONF at aol.com>
Subject: Carbonation Question

     In Eric Warner's book, "German Wheat Beer," he discusses carbonating
those beers by priming with "speise"--unfermented wort.

     In calculating the amount of speise to use, the book makes a number of
references to the percentage (by weight) of carbon dioxide that is desired in
the beer.  Mr. Warner advises that a normal weissbier will have carbon dioxide
of .7% by weight.  Most other texts talk about carbonation in terms of volumes
of carbon dioxide (e.g., weissbier usually has between 3 and 3.5 volumes of
carbon dioxide).

     My question is, does anybody know the correlation between percentage by
weight of carbon dioxide and volumes of that gas?  What is the formula for
conversion from one measurement to the other?

     Private e-mail is fine.  Thanks in advance.

                                                      Nick Franke

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Date: Thu, 08 Jan 1998 05:33:23 -0500
From: Dan Cole <dcole at roanoke.infi.net>
Subject: Re: Corma and Historical Brewing Digest

HBD'ers

I appreciate everyone's help with my questions about Korma. The most
definitive response that I got (thanks Grant W. Knechtel) was that corma is
actually a quick, dry mead (described by Pliny the Elder no less). Since it
wasn't given the time to age, it was probably loaded with higher alcohols
and phenols from spontaneous, high temperature fermentation, which
definately can be a recipe for headaches.

Also, after my post, I have been deluged (if 4 qualifies as a deluge) by
requests for information on how to subscribe to the historical brewing
digest. I have pasted the subscription information and the response you get
from the majordomo below. One word, the volume on this list is very low,
typically one message every 3-4 days.
- ------------------------------------------------------------------------------
To Subscribe: Send e-mail message with "subscribe hist-brewing-digest" to
majordomo at rt.com.

- --I've pasted in the major domo reply information below--

Welcome to the hist-brewing-digest mailing list!

If you ever want to remove yourself from this mailing list,
you can send mail to "Majordomo" with the following command
in the body of your email message:

    unsubscribe hist-brewing-digest 

Here's the general information for the list you've
subscribed to, in case you don't already have it:

Welcome to the Historical Brewing mailing list.

This mailing list is intended to be used for discussions of any form
of brewing which is not "modern". Although the guy who runs the list
(me) is primarily interested in Europe between 500 and 1600 A.D., I
hope that other times and places are also discussed.

Commercial ads and spam are not welcome. If you're not sure if
something is appropriate, ask me and I'll let you know.

This list is archived -- all your contributions are saved verbatim and
are available via ftp and the world wide web. The web page and ftp
site for medieval/renaissance brewing are at:

http://www.pbm.com/~lindahl/brewing.html
ftp://www.pbm.com/pub/sca/brewing

I am also accumulating an annotated bibliography of books and other
materials relevant to historical brewing. If you know of anything
relevant, please consider typing up the particulars and sending them
to me.

Finally, this list is also available in an un-digested form, which
means that you receive each message separately. To subscribe to that
list, subscribe to the "hist-brewing" mailing list.

Greg Lindahl (known in the SCA as Gregory Blount)
lindahl at pbm.com


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Date: Thu, 8 Jan 1998 06:25:23 -0500
From: "Norman L. Brewer" <nlbrewe at gti.net>
Subject: refractometer

Greetings,

I got a hand-held refractometer for Christmas.  It measures 0-32 degrees =
Brix, which I think corresponds to weight percent sucrose in water.  I =
found a formula on the web for converting this reading to specific =
gravity  (gravity =3D 0.9988 + Brix * .00425.  Does anyone have more =
information about predicting real wort gravity from Brix? =20

Regards,
Norm Brewer



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Date: Thu, 8 Jan 1998 03:42:37 -0600
From: "Keith & JoAnn Zimmerman" <keithzim at computron.net>
Subject: Late Addition

Had a fellow home brewer tell me that he sometimes adds a couple of pounds
of dry malt extract to his wort at the end of the boil. He claims this adds
body to the beer. I know that some people prime with malt but have never
heard of this before. Some of the brews I've entered in competitions have
come back  with comments stating my beer needs a more malty taste.  Does
anyone out there have any experience with this and what exactly it does for
your Brew?
Keith Zimmeman - Lake Jackson, Texas -  KEITHZIM at computron.net

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Date: 08 Jan 1998 08:01:01 -0500
From: Richard Byrnes <rbyrnes2 at ford.com>
Subject: Food Grade Plastics

Pat Babcock Writes...

>While we're discussing food grade colors, I have a BLACK HDPE bucket that
>originally contained Durkee taco seasoning. Color has no bearing.



Sheesh Pat, and you thought my beers had a "house" flavor, well this
certainly explains your last Graf Vienna!   (heh heh heh, that's a joke son,
a knee slapper!)

Rich Byrnes
about 20 miles east, give or take, from Spencer Thomas and Jeff Renner
Fermental Order of Renaissance Draughtsmen

Regards,_Rich Byrnes Jr
Pre-Production Systems Analyst                 \\\|///
phone #(313)390-9369, fax #390-4520_______o000_(.) (.)_000o
rbyrnes2 at ford.com                                (_)

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Date: Thu, 08 Jan 1998 07:51:58 -0600
From: Randy Lee <rjlee at imation.com>
Subject: Infusion versus step mashing

Now here's a discussion that I'd like to see a *lot* more about.

I recall a discussion about a brewpub? out west somewhere (my memory is
good, just short) that started out with infusion, went to step and went
back to single infusion due to problems with haze and the like.

I assume that this has to do with particular grains rather than the
theoretical limits of the techniques. What I'd love to see from the
collective is a list of malts that can cope with single infusion and
ones that require step infusion. Or better yet an explaination from the
better educated (beer theory wise) of us which indicators point to which
technique can/should be used.

Perhaps Jethrow can pull himself out of his "studies" long enough to ask
the question at Seibels. I do notice that he hasn't had much time to
comment very much as intended ;-)

Anyway, this subject is one that is near and dear to my heart, but I
haven't had the depth of training to answer the question yet. I'd be
happy to compile the list and present it back on this forum if I can
some input from the collective....

Randy Lee
Viking Brewing Company
Dallas, WI.
rjlee at imation.com

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Date: Thu, 08 Jan 1998 09:46:14 -0500
From: Tom Clark <rtclark at eurekanet.com>
Subject: Food Grade HDPE

Many deli's and bakeries get their icings and many other products in 5 
gallon buckets.  These of course are food grade HDPE.

Our local Kroger store usually has a few available.  We also have a 
large donut place nearby where HDPE buckets are used.

Check at such places near your home.  They may charge a token amount for 
them.  (.50 - $1.00) but, you can be more sure of the quality.

Tom Clark


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Date: Thu, 8 Jan 1998 09:48:55 -0500 (EST)
From: Joe Rolfe <onbc at shore.net>
Subject: Re: Lactic vs Phos acid

>------------------------------
>
>Date: Tue, 06 Jan 1998 20:07:08 -0600
>From: "Raymond C. Steinhart" <rnr at popmail.mcs.net>
>Subject: Lactic versus phosporic acid
>
>What would be better for pH adjustment of sparge water?
>Lactic or Phosphoric Acid?
>Where can I get Phosphoric Acid?
>I am running in the mid 9's after boiling my water and beleive I am in
>the 75 to 150 ppm of total hardness.

while doing some test brews with reasonably soft water and ph in the mid 7 
range i tried both.  i could not detect much if any difference. i used to add
it to the mash tun (enuf to get a ph of 5.5) and then again to the kettle
if required to get 5.4ish pre boil ph) .  niether volume was large (~20ml
undiluted to a mash of about 100gal volume  and same for a kettle vol
 of 160gal).  i never did get a chance to send the beers out for full
testing, but a taste pannel we set up could not find any differences flavour 
wise.  clarity onthe other hand appeared to be better with lactic. not sure
is this has much to do with the "rumor" that phos causes a decrease in
calcium - as the final testing was never done.

my mentor and others in the biz leaned tword lactic just for the fact is 
is more compatible with grain in the mash. after that i did use lactic 
more for process and phos for acid washing tanks.

small qty of either was difficult to find (i was looking for say 1 gal of each)
i found some places that would sell large drums, but a min qty for a reasonable
price was 5gal.  some homwbrew stores might have small qty (litre or so).
i think both were around a $10/gal but i dont have the invoices here....

good luck and experiment your process and water is way different than mine.
joe rolfe

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Date: Thu, 08 Jan 1998 10:01:24 -0500
From: Spencer W Thomas <spencer at engin.umich.edu>
Subject: Re: High Altitude Brewing Record 

And maybe some CA homebrewers can go for the "low altitude" brewing
record in Death Valley, eh?

Hmm.  I wonder if it's possible to brew on a submarine.... :-)

=S

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Date: Thu, 8 Jan 1998 08:58:04 -0600
From: lheavner at tcmail.frco.com (Lou Heavner)
Subject: pooped yeast...

     
     From Ron LaBorde:
     
     >>>>If your bock was OG way up there, say, 1.070 or so,  probably you 
     would
     need a fresh yeast.  I have read that Dopplebocks, etc., wear out a
     yeast.  I really do not understand this,  I have really eaten a lot at
     partys and I wasn't worn out.!!!!
     Since you had a relatively normal OG, I would go ahead and reuse the
     yeast.<<<<
     
     Well Ron, 
     
     Imagine that the party lasted a week to 10 days, you were locked in a 
     room with many many other partiers, and all you had to eat was chili 
     and bean dip, same as everybody else!  Now further imagine that there 
     was an airlock on the window, so some fumes could leave, but no fresh 
     air could enter.  Tell me how anxious you'd be to do it all over 
     again!! ;)
     
     Lou - born again coon-ass brewing in Austin, TX (formerly 
     unincorporated Travis county)

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Date: Thu, 8 Jan 1998 10:17:04 -0500
From: MacRae Kevin J <kmacrae at UF2269P01.PeachtreeCityGA.NCR.COM>
Subject: Mixmasher results

I've attempted two batches with a modified Mixmasher system.  

In my first trial, not wanting to fool with dangerous AC current, I used
the 
motor from a DC powered pencil sharpener.  It was a bit underpowered.  
I thought 'more power is good' so I used the V8 out of an old 
truck parked on the lawn.  Also upgraded the plastic fan blade to use 
the stainless (plastic would scratch and allow bacteria to grow) 
feathering prop off a neighbors 40 foot Catalina.  I must have had it 
going in reverse because the mash un-mixed, fully separating.  
The grain reformed into whole kernals and went back into the husks.
That will teach me to walk away and watch a football game.  

In batch #2, I recrushed the malt, I've got to motorize that thing!  
26 lbs took me almost 30 minutes, with some power I could 
probably get that down to 30 seconds.  Well, I fired up the 
MonsterMixer(TM) and all looked good for a while.  Good stir, 
nice mixing.  Then the most amazing thing happened.  
The downward force of the boat prop started pulling the 
engine into the mash.  Obviously the railroad ties I mounted the 
engine on couldn't hold up to the power of the mighty Ford.  
The whole contraption collapsed inward on itself creating a 
black hole on my porch.  It sucked all lite for miles around.  
That's right lite- Bud, Miller, Coors...  Lite.  All Lite beer has 
disappeared from the shelves.  Neighbors who never appreciated 
my homebrew are now knocking on my door begging for some.  

For reference both were 18 gallon batches with about 26 lbs of grain 
in a 10 gallon Gott.

Well I'm out a cooler, truck engine, half sack of Pilsner malt and 
neighbors are rapidly depleting my hb reserves.  Not bad for the 
a trial run.

Kevin MacRae
Kevin.MacRae at PeachtreeCityGA.NCR.COM



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Date: Thu, 08 Jan 1998 09:48:25 -0600
From: Adam Rich <rich.adam at mayo.edu>
Subject: pH: when to measure/ chill haze/ boiling kettles

Hello Everyone:
        I have a simple question that I have wondered about for some time.
When do I measure th the pH of my mash, and sparge water?  I know that the
mash pH should be between 5.1 and 5.7, and that I take a small sample of
the wort, let it cool to room temperature, then measure the pH.  I usually
take the sample a few minutes after starting the mash.
        How about sparge water?  Should I take it before heating, after
heating, then cooling my small sample, or at 170 F?  Certainly a higher
temperature will affect the pH reading, so measuring the pH of hot water is
out.  I have been merely adjusting the pH before heating.  Is this the
common practice?
        Finally, I am becoming more critical of my methodology because my
single infusion (typically 157 F) english-style ales consistently have
chill haze.  I suspect it might result from several problems: 1) sparging
with nearly boiling water (maybe it is starch?  I do batch-sparging and I
do it fast so that the top of the grain bed gets hot but the bottom never
does, hence the 'overheated' water), or 2) high pH while mashing/ sparging
(maybe I have 'large' proteins thus contributing to the chill haze).
        Finally, what is the bets place to buy a 5-7 gallon brew kettle?
How much should I expect to pay?  I have pretty much ruled out stainless
since it costs too much.  How about enamel or aluminum?  I currently have a
4 gallon stainless and am mighty tired of boil overs!
thanks,
Adam Rich
Adam Rich, PhD					Home:
Department of Physiology			855 First St. NW
Guggenheim 8					Rochester, MN 55901
Mayo Clinic
200 First St SW
Rochester, MN 55905

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---