---

	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:
  straw blowoff... danger! (Al Korzonas)
  Airlox - correction (Steve Alexander)
  On Esters ... (Steve Alexander)
  Adequate Ventilation ("Anton Verhulst")
  Big Bend Brew-Off '98 Competition (Edwin Chesley Roberts)
  Force Testing ("Louis K. Bonham")
  Extract vs. All-Grain/Making Pale Extract Brews (Jim Anderson)
  Non lead brazing ("Lorena Barquin Sanchez")
  Aeration with Oxygen ("Lee B.")
  RE:Wort Stability Tests (Jeremy Price)
  Re: Wort stability/sanitation (Chasman)
  Simple Effective Airlock (Fred and Sue Nolke)
  re: Small pumpkins v large pumpkins (Dick Dunn)
  homebrew cooking - spent-grain bread (smurman)
  WST, Mash Calcs.... (Chasman)
  Airlocks - some answers (Steve Alexander)
  RE: Traquair House Ale ("Ridgely, William")
  Water analyses (A. J. deLange)


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


Date: Mon, 3 Nov 1997 14:03:20 -0600 (CST)
From: Al Korzonas <korz at xnet.com>
Subject: straw blowoff... danger!

Dan writes:
     What I found was that the plastic cups with lids and the 
     bendable clear plastic straw (often free with a soda purchase at 7-11, 
     etc.) work great.  I placed one end in the rubber stopper and the 
     other end in the cup filled with water, it was also effective as a 
     blowoff tube. <snip>

Oooh... dangerous advice.  Take it from someone who painted the ceiling
with a batch of brown ale using 5/16" ID plastic tubing (as per Charlie
Papazian's advice), who then proceeded to brew several dozen uneventful
(but no less delicious) beers using a 1/2" ID blowoff hose, until two
more batches painted the ceiling.  No... if there's any chance of blowoff,
I use a 1" ID (1.25" OD) blowoff hose which fits into the neck of a 6-,
5-, or 3-gallon carboy without *any* stopper at all.

It only took three batches for me to learn.

See if you can learn with fewer...


Al.

Al Korzonas, Palos Hills, IL
korz at xnet.com

My new website (still under construction, but up-and-running):
     http://www.brewinfo.com/brewinfo/

Return to table of contents


Date: Sun, 02 Nov 1997 14:16:14 -0400
From: Steve Alexander <steve-alexander at worldnet.att.net>
Subject: Airlox - correction

Al Paulson helped me recognize that I have posted something quite
silly.  I wrote ...
>My real concern is the amount of non-enzymatic browning, and resultant
>staling 

I revised that sentence once too often.  I think that I am seeing oxygen
inclusion and resulting oxidative staling.  Also that the oxygen is, I
*suspect*, causing some sort of non-enzymatic oxidative browning,
possibly involving phenolic oxidation reactions - tho' the cause is far
from certain.  Non-enzymatic browning does not result in staling
compounds.

I have a simple experiment underway to determine whether the darkening
color shift is due to oxygen or 'yeast dropping' as several people have
suggested.  Will report later.



Return to table of contents


Date: Sun, 02 Nov 1997 15:22:09 -0400
From: Steve Alexander <steve-alexander at worldnet.att.net>
Subject: On Esters ...

Jeff Renner and Al Korzonas request a deeper discussion of of esters
formation in beer. 

The mechanism is enzymatic formation from an alcohol (fusel alc. or
ethanol) and a coenzyme-A(CoA) activated compound, often a fatty acid. 
The CoA compounds may result from fatty acid synthesis, fatty acid
catabolism, activation of existing fatty acids and also, (perhaps a
minor mechanism?) acyl-CoA may arise from amino acids metabolism.

Due to enzymatic action ...
  ethyl acetate   arises from ethanol and acetyl-CoA
  ethyl caproate  arises from ethanol and caproyl-CoA
  isoamyl acetate arises from isoamyl alcohol (a fusel 
    alcohol) and acetyl-CoA.

Ethanol and acetyl-CoA both form in high concentrations directly from
sugar fermentation. Ethyl acetate, formed from these two most common
precursors, is the most common ester in beer. Caproyl-CoA is an
intermediate product of fatty acid synthesis.  This sort of compound may
appear at high levels during yeast growth under low oxygen, low fatty
acid wort conditions.

Control - Since yeast enzymes are involved in ester formation, careful
selection of yeast strain is a primary means of ester control.  Wort
oxygenation or fatty acid addition during yeast growth reduces
caproyl-CoA and other fatty-product-CoA compounds and should reduce the
related ester levels, but acetyl-CoA is always present. Reducing fusel
alcohol levels will of course reduce the levels of the corresponding
esters, but of course ethanol is always available in fermenting wort. 
Ester formation shows a strong positive relationship with fermentation
temperature.

An abstract of a recent paper, 'Investigation into Ester Formation in
Beer', N.Rossey, in 'Cerevisia and Biotechnology' implies the following
practical results ...
1/continuous addition of yeast -> more esters.
2/low pitching rate -> more esters
3/high pitching rates -> more ethyl acetate
4/high gravity SG -> more esters
5/adding amyloglucosidase -> more esters
6/more oxygen -> less esters
7/rising fermentation temp -> more ethyl acetate
8/top pressure had little effect, except that low top pressure during
initial fermentation -> more esters.
9/adding fatty acid(stearic) -> little effect
10/addition of casein & yeast nutrients -> more ethyl acetate
11/added Leucine -> more isoamyl acetate.

Steve Alexander


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Date: Mon, 03 Nov 1997 16:55:51 -0500
From: "Anton Verhulst" <verhulst at zk3.dec.com>
Subject: Adequate Ventilation


knoroa at rbnet.com saiz:
>I've been banished to the unheated, detached garage ...and am
>concerned about maintaining enough ventilation for my propane burner. `

No scientific studies but I've been brewing in my garage for about 4 years.
I keep the door fully open and have the burner maybe 5 feet from the door -
I'm still here.

It will be winter soon on this side of the equator and
it can be a b*tch when the temp gets below 0F (about -12C).
Hoses to run the chiller have to be kept above freezing (not to mention
your faucet) and get waterproof gloves.  I also switch from the 30K BTU burner
to the 125K BTU burner when the temps get below freezing (for 10 gallon
batches).

I *hate* winter but love good beer.

- --Tony V.

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Date: Mon, 3 Nov 97 17:27:16 18000
From: Edwin Chesley Roberts <nedr at freenet.tlh.fl.us>
Subject: Big Bend Brew-Off '98 Competition

Big Bend Brew-Off '98, an AHA sanctioned competiton, will be held on
January 17, 1998.  Big Bend Brew-Off '98 is being presented by the
North Florida Brewers League.  Official rules may be obtained from the
NFBL's web site - www.freenet.tlh.fl.us/~northflo, or by e-mailing the
Competition Organizer, Ned Roberts - nedr at freenet.tlh.fl.us.

Entries are due January 14, 1998, all AHA styles are eligible.  Prizes
have been donated by various business, such as The Homebrew Den,
Gulfstream Brewing Products, Sunset Suds, Brewing Techniques Magazine, 
Hops Union, Baker & Crosby, L.D. Carlson, the Buckhead Brewery and
Grill, and the American Homebrewers Association.

Any BJCP qualified Beer Judges interested in volunteering their time
and effort should contact John Larsen, Judge Director, at
850-681-9563, or jlarsen at nxus.com

Return to table of contents


Date: Mon, 03 Nov 1997 17:36:18 -0600
From: "Louis K. Bonham" <lkbonham at phoenix.net>
Subject: Force Testing

I heartily second Charles Hudak's admonition regarding 
wort stability and force testing.  Dr. Farnsworth calls
these "no-brain, no-excuse" tests that brewers should
run on EVERY batch.  Incredibly simple to do . . . .

Here are the three I typically use, which are adapted 
from Dr. Farnsworth's lab manual.  Two are extremely
simple and require nothing special; the third requires
a little bit of lab stuff:

1.	Wort stability test

Equipment needed: either a 250 ml erlenmeyer flask or 
a baby food jar; wine thief or turkey baster if needed 
(i.e., you don't have a sample port on your fermenter).

Procedure: sterilize the flask/baby food jar with bleach, 
idophor, Star-San, pressure cooker, autoclave, gamma 
radiation, or whatever. [I suggest using a chemical 
sterilzer, then covering the top with foil and baking 
for 1 hour in a 300F oven, then allowing to cool while 
covered.]  Also sterlize the wine thief or turkey baster 
if you'll need to use it to get a sample.

After you've run your wort into your fermenter and aerated,
BUT BEFORE YOU PITCH THE YEAST, take a sample of about 100
ml from the fermenter to the flask/jar and cover immediately.  
(If you use a sample port, be sure to either flame or wipe it 
down with alcohol first.)  Set the flask in a warm (80-85F), 
dark place, and check it every 12 hours or so.  (You can rig 
up a simple water bath using a 1 quart plastic container and 
a $10 aquarium heater, but it's not absolutely necessary.) 

If the wort remains clear and shows no signs of growth for 
more than 48 hours, your sanitation is probably good enough.  
If it stays clear for 72 hours or more, you are really doing 
things right.  If it shows any signs of growth or turns cloudy
within 24 hours, you've got big problems.  

Once the sample turns cloudy or shows growth, take a sniff / 
sip of it to gather a little data of what's likely to be 
growing (vinegar? rotten eggs?  vegetative? etc.).

2.	Forced fermentation testing.

Equipment: same as (1)

Procedure: Same as (1), only pull the sample *after* pitching.
After 48-72 hours in the warm, the yeast should have munched 
all of the sugars they're likely to be able to, and so
the gravity of the sample should be the minimum final gravity 
you should expect for that batch.  You can speed this test up 
dramatically by using a stir plate, but again it's not necessary.

3.	Pitched wort stability test.

Equipment: same as (1), plus actidone solution and a 
syringe with a 0.22 micron filter.  (If you are interested,
write me and I'll give you the recipe for the actidone 
solution.)

Procedure: same as (2), only add 1 ml of the actidone (a/k/a
cyclohexamide) to the sample.  MARK THIS SAMPLE AS POISON --
actidone is nasty stuff and you don't want to drink this by
mistake.  Incubate as in (1) -- the actidone will kill all the
yeast, so if anything grows in it it's bacterial.  

If you run (1) and (3), and (1) turns out OK but (3) fails, then 
you know your yeast was your contamination vector.  If it passes
(3) but fails (1), you probably have a wild yeast infection (or
didn't sterile your equipment enough and some old beer yeast got 
through). Test (3) is especially important if you are repitching 
yeast.

Again, these are very easy to do, and if you sterilize a bunch 
of flasks in advance they take essentially no time to run.

Louis K. Bonham
lkbonham at phoenix.net

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Date: Mon, 03 Nov 1997 16:50:25 -0800
From: Jim Anderson <jander at xmission.com>
Subject: Extract vs. All-Grain/Making Pale Extract Brews

It seems to me that the best hobbies are those that people can tailor to
suit themselves -- as much or as little "complicated" as they happen to
like.  Some aviators pursue instrument and commercial ratings -- I'm
happy with my VFR ASEL.  Some martial artists don't care to compete in
tournaments -- I do (some go on to black belt rank -- I probably
won't).  Some fly fishermen don't tie their own flies -- I do.  Some
computer "nuts" program in assembly language (I did), others won't do
anything that can't be done with a mouse click.  And when it comes to
brewing, I'm more than satisfied being an extract and specialty grain
brewer.  Is it laziness?  I think not.  I also grow my own hops and have
yeast culturing facilities that many would envy (sometimes I wonder if I
don't enjoy culturing MORE than brewing!).  Quite simply, I brew the way
that *I* want to, I brew the styles that *I* like, and I make them very
well.  Well enough that I've had hardcore all-grainers suggest that I
enter them into competitions.  But I don't because I don't want to. 
Just as I don't want to invest the time or money for going all-grain.  I
want my hobby to fit me, and not the other way around.  Care to
criticize me for that?  Help yourself, I couldn't care less (although
others here might prefer that you flame me via private email).  Quite
simply, I'm happy with my hobby as it is, and I'm happy with my
product.  I'll grant that I could probably make "better" beer using
all-grain, but I'll likely never know.

The consensus seems to be that it's difficult to make a pale extract
brew.  I agree with that, but through experimentation, I've come up with
a basis for a recipe that seems to work quite well.  The main purpose of
this post is to share that.  If anyone has any other and/or better
suggestions, I'm sure that ALL of us extract brewers would like to hear
them!  I start off with three pounds of Alexander's Pale LME, and fill
out the malt bill with Munton & Fison Extra Light DME.  Sometimes,
depending upon what I'm shooting for, I'll substitute some Laaglander's
Extra Light DME for the M&F.  This makes for a nice golden-colored
brew.  Not as pale as Budweiser, et al, actually just a SHADE darker
than Pilsner Urquell, for instance.  I "specialize" in pilsners and pale
ales, and this basic recipe has served me quite well in doing so.  I
hope that others can put this to good use.  I agree that the freshness
of the extract is an important factor, even though I've used dated
extracts successfully.

In closing, I'm normally a lurker here and I intend to stay that way
(once again, my personal preference).  I never intended to participate
in the extract vs. all-grain debate, but here's my $.02 anyway.  I
mostly wanted to pass on my formula for pale extract brews.  But while
my head's out of the trenches, let me take this opportunity to thank all
those who DO actively participate in HBD.  You've taught me quite a lot,
and you've caused me to THINK about many things that otherwise might not
even have occured to me.  To me, this is a family of sorts, in many
different ways, even though I'm the silent sort.  Thank you all, just
for being here.

  - Jim

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Date: Thu, 30 Oct 1997 06:28:35 -0400
From: "Lorena Barquin Sanchez" <mbarquin at telcel.net.ve>
Subject: Non lead brazing

Gentlemen:

I am willing to construct a wort return manifold in my Rims.  I intend to
connect the copper parts using a non-lead containing brazing, however,
reading the content of this solder, it is based on silver.  Is this safe?

Thank you,

Lorenzo Barquin
Maracay, Venezuela  

Return to table of contents


Date: Mon, 3 Nov 1997 19:51:44 -0800
From: "Lee B." <leeb at iea.com>
Subject: Aeration with Oxygen

Anyone had good success using pure oxygen aeration kits (Liquid Bread, 
Gulf Stream) to aerate your wort?

I hear that 2 quick 15 second blasts is all that's needed. That
doesn't seem like enough! Is this really enough to fully aerate a 5
gallon batch? I know some of you just shake the carboy a bit to aerate
wort, but I had no success getting complete fermentations until I used
an aquarium pump in 10 minute intervals, on/off for almost an hour.
This worked great, but I'm trying to cut down the time this takes, by
going to pure O2. 

Thanks in advance.

Lee B.
leeb at iea.com



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Date: Mon, 03 Nov 1997 23:27:17 -0500
From: Jeremy Price <pricejy at UCBEH.SAN.UC.EDU>
Subject: RE:Wort Stability Tests


Charles Hudak Wrote:

>Before everyone sounds off about how bad 12 or even 24 hour lag times are,
>let me ask ALL of you: Have you ever done a wort stability test?
>
>Yeah...didn't think so.
>
>I have. In my brewery, oxygenated, unpitched wort has gone four days
>without ANY off flavors or fermentive activity when incubated at 80-90F.
>That being the case, I have no concern for long lag times because they
>*will not* be the cause of off flavors.
>
>I suggest periodically doing WST to ensure that your sanitation practices
>are up to snuff. This, if nothing else should allow you to *relax* about
>those "long" 12 hour lag times.
>
>C--
>

Charles,
   This is the HOMEBREWER'S digest. I don't believe that a single
homebrewer on this forum is going to spend the time and money to brew a
batch of beer, then let is sit unpitched for 4 days at 85F to see if there
are any off flavors. 
	Homebrewers working outside, out of basements, garages, and kitchens using
non-enclosed brewing systems DO need to worry about fermentation lag times
because for us, the likelyhood that we are going to inoculate our wort with
an unwanted  nasty organism is much greater. Our brewing areas are
(microbiologically speaking) filthy, and our equipment is by no means
sterile. Without a healthy yeast population to remove oxygen, alter the pH,
and to remove the simple fermentable sugars, wild yeasts and bacteria can
and will begin to multiply. I would be willing to bet that if homebrewers
did conduct these stability tests there would be alot of bogus beer going
down the drain.

Jeremy Price
Department of Molecular Genetics
University of Cincinnati

Return to table of contents


Date: Mon, 03 Nov 1997 22:57:29 -0800
From: Chasman <cwhudak at gemini.adnc.com>
Subject: Re: Wort stability/sanitation

The following is a reply that I sent via personal email before I knew that
Paul sent his email to the digest:

Paul wrote:

>I'm interested  of the details of how this test was conducted.  Was this 
>five gallons of wort in a 6.5 gallon glass carboy or a 7 gallon plastic 
>pail with room air above the wort?  If not, then maybe it's not 
>representative of most HB set-ups, where cooled wort is exposed to a fair 
>amount of room air either in the fermenter or on it's way into it. Unless 
>people are working in filtered clean rooms, or have a closed system 
>between kettle and fermenter, then the wort will be most likely exposed 
>to enough airborne bacteria for potential harm.

Charles replies:

I've done a WST in the commercial brewery where I work--where I use
commercial size "pitchable Yeast" from White Labs. The test reflects the
conditions in my brewery. Aerated, unpitched wort is sampled off of the
transfer line from the heat exchanger to the fermentor into a sanitized
glass jar and left loosely capped in a warm corner of the brewery for 3-4
days. *Every* time that I've done this, the results have been the same--a
testimony to my anal retentiveness for cleanliness in my brewery. The whole
point is to get results that reflect  *your* brewery. If your wort is only
stable for 1-2 days, then you need to use that information and pitch a
large healthy starter so the wort doesn't sit for 24 hours. If, OTOH, your
wort is stabile for 4 days, then why are you bitching about 24 hour lag times?

If you try this at home, it will adequetely reflect your practices and thus
your sanitary conditions, room air and all. Before you keep throwing
conjecture my way why don't you do the damn test and find out if there is
"enough airborne bacteria for potential harm". Everyone seems content to
give a lot of "what ifs" but isn't willing to do the work to back up their
diatribe. I have. BTW, my brewery doesn't have a HEPA filter, nor is it a
clean room. The fermentor is full of "room air"...300 gallons of it, I
might add, as is the sample jar.

Paul wrote:
>
>Right now, my QA consists of occasionally putting a few samples of 
>bottled beer back for 6-12 months or more and seeing if I get any 
>gushers, off-flavors, etc. that would indicate bacterial activity (yeah, 
>I know that's a little like cllosing the barn door after the cows 
>escape). I've done some plates with both wort and finished beer in the 
>past using HLP and came up clean, so I don't mess with it anymore. This 
>isn't to say I've never made an infected beer.  I just haven't had that 
>misfortune in many years, knock on wood.

Charles replies:

Great, you've done some QA on your beer. QA is an ongoing process though,
you can't do it once and stop. Plating can give misleading results if it is
done wrong. Did you use an innoculating loop or did you use a good sample
size, say 5-10mL on the agar bed? In a large volume of liquid, there are
going to be *very* few bacteria and the chance of picking some up on a loop
is very slim. 

Paul wrote:
>
>Also, potential for bacterial contamination is only one area of concern 
>in underpitched wort/long lag times, in my experience and from what I've 
>read.  Increased levels of esters, esp ethyl acetate (the solventy ester) 
>can be problematic in underpitched beers, especially with some strains of 
>yeast.  I've noticed it especially wih some of the "abbey" beer yeasts.  
>I think since most of these beers are high gravity brews, the problems of 
>underpitching are exacerbated.

Charles replies:

I don't recall mentioning underpitching in my post. Don't use this as an
excuse to go off on the "underpitching" tangent. They are two separate
issues. But since you brought it up, have you ever done any yeast viability
or cell counts on your slurry? I haven't, since I don't have the necessary
(and expensive; godamn boss won't buy them) equipment. I find it ironic
that the same folks who are pissing and moaning about White Labs cell
counts don't mention (well, one guy admitted not having done it) ever
having done cell counts or viability testing on their starters. So, just
how is it that you are sure that you're pitching the "optimum" 1x10E6
cells/mL/Plato if you've never counted? You may still be underpitching by a
factor of 2-5 or more without even knowing it. BTW overpitching is just as
detrimental and causes just as many fermentive and flavor problems as
underpitching. You might want to keep that in mind next time you toss in
that half gallon starter (tongue firmly in cheek).

While low pitching rates may increase ester formation, so do high
fermentation temps (as low as 68F with some yeast) and inadequete aeration
(low wort O2 levels). Low 02 levels are especially problematic in high
gravity beers. While there are many problems associated with underpitching
(and overpitching), many of these problems can also be caused by other
factors.

Paul wrote:

>Speaking of cleanliness, have any of you seen or tried "BioSentry" 
>sanitizer.  I found this stuff at a farm store, and it's labelled as 
>being for cleaning/sanitizing poultry houses, dairy plants, food 
>processing equipment, hand rinsing, etc.  I don't have the exact 
>proportions in front of me, but the stuff is a mixture of an Iodine 
>complex and Phosphoric acid.  One ounce in five gallons gives 25 ppm of 
>active iodine.  Sanitation contact time is 1-2 minutes with air dry, just 
>like BTF.   
>
>However, it can be used at "double strength" to help clean surfaces of 
>grime, something BTF can't do. Also, if you're cleaning with Red Devil 
>lye or another form of  NaOH, you're got the phos acid to neutralize it.  
>
>I clean with All Free & Clear powdered dishwasher detergent, then follow 
>with BioSentry. While I like how PBW works, it's kind of pricey in those 
>small packets.
>
>Best part: it's a lot cheaper than BTF which runs anywhere from $9-$14 a 
>quart, depending on the sources I've seen. and cheaper than the phos acid 
>mix from Five Star.  My local HB shop sells BioSentry for $22 a gallon.  
>You may find it a bit cheaper if you see it in a farm store, if you have 
>one nearby. 

Charles replied:

I use several things: PBW, NaOH, Bleach, Solution I/O and CMC

I've found that there are just some things that PBW doesn't clean well. It
will not remove the sugar soils that build up on my mash screens. An
overnight soak with caustic and bleach cleans em great. I like it, though
for CIP in my fermentors.

For a manual cleaner, CMC (chlorinate manual cleaner) is great. It's a
sodium carbonate powder with chelating agents, chlorine and surfactants--a
great alkaline cleaner for soaking small parts and hand scrubbing and much
cheaper than PBW. It also comes from Five Star.

Solution I/O I get from our dishwashing service. It is an Iodophor of sorts
with a polyol surfactant to aid in surface wetting. Great no rinse at 25-50
ppm. I get it for about $15/G in a five gallon drum (at commercial strength
too, which is great; goes alot farther). I use this in applications where I
want "no-rinse" capabilites.

I still use bleach though in certain application for sanitation. It works
great for sanitizing the heat exchanger; it's very strong and effective and
is alkaline so it removes any residual soil as well. I just make sure to
flush the hoses with wort or water before using them to tranfer.

Speaking of which...gotta go to work...it's keg washing day ;(

C--

Charles Hudak
cwhudak at adnc.com

"If God had intended for us to drink beer, he would have given us stomachs."
- --David Daye



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Date: Mon, 03 Nov 1997 22:02:55 -0900
From: Fred and Sue Nolke <fnolkepp at corecom.net>
Subject: Simple Effective Airlock

Somewhere around batch number 5 I had the clogged airlock/repaint the
ceiling experience.  Messing with airlocks had been a conceptual problem
since seeing the open fermenters in England, and the ceiling repaint
tipped the scales.  I switched to a piece of single or double saran wrap
with a rubber band around it.  First few days of primary, the rubber
band is relativly loose.  It gets doubled or tripled as the batch goes
from secondary to conditioning.  Sending up north to my brother gets an
extra rubber band for safety sake.  Not one bad batch out of 78, and my
brother keeps it for months in carboys.  Suspect low permeability of
saran wrap is a factor.  Also works well for cleaning and sanitizing
solutions in carboys, usually four layers, i.e. folded twice with
heavier rubber band.      Sort of a bump in the road to ever higher tech
brewing.
Fred Nolke


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Date: 3 Nov 97 23:51:16 MST (Mon)
From: rcd at raven.talisman.com (Dick Dunn)
Subject: re: Small pumpkins v large pumpkins

Tidmarsh Major <tmajor at parallel.park.uga.edu> wrote:
> I recently read an article on cooking with pumpkins, and the authors
> recommended the smaller cooking pumpkins rather than the larger
> jack-o-lantern carving pumpkins because the smaller ones have a thicker
> shell, and thus more meat...

I've heard this too...I think it falls into "conventional wisdom" and all.

But this year, we were given a rather large pumpkin by some friends.  It
was 80 lb, and this was second-largest on a vine that had 5 fruits.  So,
although it was nowhere near in the record category, it certainly was in a
category larger than "typical eating pumpkin."  I made it into a Jack'o'
lantern.  The flesh I carved out for the eyes/nose/mouth, once scraped and
skinned, was by itself enough for a couple of pies.  It was more than 2"
thick.  Now, perhaps this is thin-skin in a relative sense...the pumpkin
was large enough for both (mature) barn cats to occupy the interior at the
same time if we could have convinced them to do so...but >2" flesh is
plenty in any absolute sense.

Oh...the other thing is that the cooked-down flesh of this pumpkin was
nicely sweet.  It wasn't the sweetest I've had, but it was on the sweet
side of what you'd want for a squash, and it also had as good a taste/
character as ever I've had from a pumpkin.
- ---
Dick Dunn       rcd, domain talisman.com       Boulder County, Colorado  USA
   ...Reality is neat!  It works even if you don't believe in it!

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Date: Mon, 03 Nov 1997 23:26:24 -0800
From: smurman at best.com
Subject: homebrew cooking - spent-grain bread


I thought I'd share some thoughts and recipes on cooking with
homebrew.  I figure I'll post some of my recipes to the digest with
hopefully some regularity.  I'm not doing this 'cause I'm some super
chef, but just to maybe spark some interest and discussion.  Heck, we
all have a lot of homebrew to experiment with, especially with the
winter brew season upon us.

The first point I would make is that the worst beers for drinking
probably make the best beers for cooking.  All those strong off
flavors that make your mouth pucker can better stand the high temps of
cooking.  If you've had a batch of homebrew go south, don't flush it,
marinate with it.  Some of the most popular beers for cooking are the
lactic sour ones like gueze or stout or French brown ales.

Anyway, first recipe is for spent-grain bread.  All you extract
brewers can skip to the next article now.  It's for an automatic bread
machine (ABM).  If you can bake bread from scratch, you don't need my
help formulating a recipe, although maybe later I'll post my
experience using a yeast cake as a sourdough-like starter.

For 1 1/2 lb. loaf
1 cup spent grain (doesn't really matter the brew)
8 oz. homebrew (the crappier the better)

Mix the spent grain and beer in a blender (the thing you use to make
margaritas), and blend for a minute.  This is to pulverize the barley
into smaller pieces. 

Add to bread machine with,
2 1/2 cups white bread flour
1 tsp. salt
1 tbsp. vegetable oil 
2 tbsp. sugar (yes, we like sugar)
2 tsp. bakers yeast (e.g. Red Star)

Adjust for your bread machine.

This makes a light fluffy loaf actually, not what most would expect.
You can adjust the sugar, oil, and ABM settings if you want a
different style.  Basically just adjust any recipe down by about 3/4
cup of flour and 2 oz. of liquid for every 1 cup of spent grain
substituted.  Enjoy.

SM

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Date: Tue, 04 Nov 1997 00:45:39 -0800
From: Chasman <cwhudak at gemini.adnc.com>
Subject: WST, Mash Calcs....

I've racked my brain and searched in vain...

I can't find the reference which I read quite a while back in probably a
Brewing Techniques or New Brewer Mag about QA tests. I've searched all of
the books in my library and run multiple searches on the internet to no
avail. I do recall that one of the articles that I read mentions WST along
with forced attenuation testing. Oh, well. I do know that Siebel offers a
Wort Stability Test as one of their laboratory services.

In any event, to perform a WST, collect a small sample (6-12oz) of aerated
unpitched wort in a sanitized glass jar. Loosely cap the jar and store in a
dark, warm place for several days. At the end of the test, check for
visible fermentive activity and then perform a sensory analysis of the wort
(look, sniff, taste). It should taste like fresh wort and have no unusual
odors/flavors nor strange things growing in it and be fairly clear with a
modest trub sediment. Try several small samples and check one per day for
3-4 days to give you and idea of your stability window. After opening and
analyzing, discard the sample, it is no longer viable for further testing.

That's it, pretty damn simple.

BTW George, I'm not so naive as to think that none of you have ever done a
WST but judging by the number of emails that I got from people who've never
even heard of a WST, let alone performed one, I'd say you...we're...in the
minority.

George also writes:

> While a properly performed wort stability test can show you that your 
>     beer won't suffer from microbial damage during the lag, there are two 
>     factors Charles has forgotten:
>     
>     1.  A long lag can lead to off flavors produced by the yeast 
>     themselves.  In my experience, slight esteriness can form in beers 
>     with a 12 hour lag.  This is really most noticeable in clean styles 
>     like Alts and most lagers.
>     
>     2.  There could be contaminants in the pitching yeast.  A wort 
>     stability test won't tell you diddley about them, yet they can pose a 
>     real threat to the beer.
>

Neither of these are things which I've "forgotten". I've never stated that
long lag times are better than short ones. I've only been debating the
definition of long. If you pitch large quantities of dormant yeast, you
will have long lag times just as if you underpitched. When does it really
become a problem? The yeast that I use is a fairly strong ester producer;
mostly ethyl acetate but some isoamyl acetate as well. It produces
noticeable esters even down to 55F and even in *well* pitched wort with lag
times of 2-4 hours. Four hours or twelve, doesn't make a difference with
this yeast. I've also underpitched and had 24 hour lag times and gotten no
esters using a different yeast. Many of the problems regarding ester
formation are strain dependant. Some yeasts can be totally abused:
underpitched, fermented too hot, pitched into oxygen deficient wort and
they will still ferment totally clean.

There *could* be contaminants in the pitching yeast? I'd bet that there
probably *are* in even the cleanest of starters, small OR large. I still
think that I'd rather have a small, clean starter than a large contaminated
starter.

My bladder feels empty, guess I'll have to bow out of this pissing contest.

On a lighter note...

Frank asks about increasing mash temp with the addition of boiling water:

Well, you use the same equation that you used originally to figure out the
strike temp, namely:

Rest Temp= (1 X W X TW) + (0.4 X M X TM)
            ----------------------------
                (1 X W) + (0.4 X M)

Where W = wt of Water used to strike
      TW = Strike temp of water
      M = wt of Malt
      TM = temp of malt

Note that the "1" is the specific heat of water and the "0.4" is the
specific heat of malt (Frank uses 0.38....)

I'll let you guys do the algebraic rearrangement to solve for strike temp.

Anyways, to calculate for a second addition of liquor add anothe term so that:

Rest Temp= (1 X W1 X TW1) + (0.4 X M X TM) + (1 X W2 X TW2)
            ----------------------------------------------
            (1 X W1) + (0.4 X M) + (1 X W2)

Where W1 = wt of initial strike volume
      TW1 = initial mash temp
      W2 = wt of hot water addition
      TW2 = temp of second addition, which in this case would be ~212

You can setup the equation to solve for TW2 or W2.

I've done both of these equations and more in an excel spreadsheet format
and I'd be happy to email them to anyone who's interested.

I've also done a relatively simple IBU calculator and a "Hop Tracker" which
utilizes info in Mark Garetz's book "Using Hops" to calculate the alpha
acid deterioration for stored hops; maybe not a big deal to HBers but it is
to me since I'm forced by my $$ pinching employer to order at least a years
worth of hops at once (shipping's cheaper you know) and need to adjust my
recipes to cope with the AA deterioration to maintain a consistent
bittering level.

And Paul, if you're still interested, I have eight fermentors: 2 7G, 5 5G
and a 6.5G plastic bucket that I use as a primary for melomels and other
pulp fermentations. It doubles as a bottling bucket (got that nice spigot
on the bottom!) I've found as I brew more and more mead, I need the fives
for aging, I've got 20G of mead and 5G of cider aging right now. Now if it
would only cool off here in San Diego so I could actually make some
homebeer.....

C--

Charles Hudak
cwhudak at adnc.com

"If God had intended for us to drink beer, he would have given us stomachs."
- --David Daye



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Date: Tue, 04 Nov 1997 05:36:26 -0400
From: Steve Alexander <steve-alexander at worldnet.att.net>
Subject: Airlocks - some answers

Does inclusion of air cause browning in beer ?

Several people have written to me doubting that air causes a color
change in post fermentation beer. Instead they suggest that apparent
darkening is from the yeast settling in the fermentor.  Yesterday I
poured a light colored lager which has been kegged for 3 months (quite
clear) and let it sit on my kitchen counter for ~15 hours.  Today I
poured a second from the same keg.  Same type glass, same fill level,
identical lighting.  When viewed against a white background the color
difference is obvious.  Exposing light colored beers to air does cause
darkening.
- --

How much air gets past an airlock ?

Diffusion of oxygen thru the water in an airlock is dependent on the
geometry of the water plug, the concentration gradient of oxygen in the
water and the diffusivity constant of oxygen thru water.
 
I just took some geometry measurements. My S-type airlock holds 7CCs of
water when properly filled and the pathlength thru the water is close to
7cm. So I calculate an average 1cm^2 cross section and 7cm length.

We can guesstimate an oxygen concentration gradient drop from 8ppm of O2
(2.5*10^-7Mole/cm^3) to zero over the 7 centimeter length.  This guess
is undoubtedly too high, and will result in a sort of upper bound
calculation of oxygen diffusion thru the airlock.

Dave Whitman provides an O2 thru H2O diffusivity rate of 2.08*10^-5
cm^2/sec  at 25C. Interestingly adding salt or ethanol to the water lowers
the diffusivity by about 40%. A lactose-water solution is about 80%
lower diffusivity than pure water. I have found 5 different formulae
which attempt to arrive at the diffusivity of gasses in solvents.  The
only commonality is that all have a term of 1/viscosity.  This explains
why several books on bioreactor design that I have consulted indicate
that highly viscous motor oil and castor oil are sometimes used in
commercial bubbler columns.

Under these conditions with a few simplifying assumption the flow rate
of O2 into a fermentor is:

Q/t = diffusivity * cross-section * (concentration gradient)

Q/t = 2.08*10^-5 cm^2/sec * 1cm^2 * (2.5*10^-7 Moles/cm^3 / 7cm)

Q/t = 7.5*10^-13 Mole/sec = 2*10-6 Mole of O2 / month

In other words, I estimate the oxygen that sneaks past an S-type bubbler
filled with water is equivalent to adding 1CC of air (not O2) every 3
months.  Thats less than the inclusion of a teaspoon of air per year!
Given my excessive guesstimation of the O2 concentration gradient this
figure is probably several times higher than the actual diffusion rate.

My conclusion is that if beer darkening or staling  in the fermenter is
due to oxidation, the oxidation is NOT attributable to O2 leakage thru
the airlock.  There is little value in re-designing the airlock.
- --

Could O2 remain from the original headspace air ?

Yes, but probably not much.  A 5gal(20L) batch of beer should produce
about 18 Moles of CO2 or about 105gal(400L) of CO2 at STP.  Plenty of
CO2 to flush the headspace of most O2.  Furthermore the fementing yeast
will rapidly absorb any oxygen dissolved in the wort.

Steve Alexander


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Date: Tue, 04 Nov 1997 07:26:47 -0500
From: "Ridgely, William" <Ridgely at cber.fda.gov>
Subject: RE: Traquair House Ale

In HBD #2548, Charlie Burns inquires:

>My next project - the perfect Strong Scotch Ale and Traquair House Ale
is my 
>target. Reading in Ray Daniels' _Designing Great Beers_ (page 290), he
lists 
>the grain bill as Pale Ale malt and Black malt only. Reading Michael 
>Jackson's Beer Companion (page 110), he lists Pale Ale malt and Roasted

>Barley only.

>Does anyone have a third reference that could clear this up? Is it
Black or 
>is it Roasted Barley?

The grist for Traquair House Ale is pale ale malt plus 1% roast barley.
There is no black malt used. Hops are whole East Kent Goldings. This
info comes directly from the brewer. I believe Greg Noonan also verifies
this grain bill in his Brewers Publications book on Scotch Ales.

Bill Ridgely
Alexandria, VA


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Date: Tue, 4 Nov 1997 13:36:52 -0500
From: ajdel at mindspring.com (A. J. deLange)
Subject: Water analyses

smurman at best.com asked about the value of water reports surmising, quite
correctly, that there is seasonal variation and wondering about the worth
of the averages. There is, of course, some value in the averages and if
water suppliers would give the standard deviations instead of the minimum
and maximum, which most of them seem to do, the data would be even more
valuable. I see in a local area report, for example, that the average
alkalinity is 36.4 with the minimum and maximum values being 19 and 54
respectively based on 16 tests over the period of a year. That's useful
information: the water just isn't very alkaline ever. I can tell from this
that I might have trouble sometimes with a Pils and would need to
supplement substantially for a IPA but I couldn't calculate mash pH (not
that I'd want to do that for every brew) terribly accurately. I'd be better
informed if they'd put in one more column telling me that the standard
deviation was say 10 ppm.

The composition of the local water doesn't vary that much with the seasons
around here: we don't get that much from snow melt and they don't salt the
roads very often but there are parts of the country where the changes can
be quite dramatic. What they do do around here (and most everywhere else)
is goose up the chlorine in the summer time. It just makes sense in terms
of getting microbe free water into the consumers house. The local water
authority included a little note with one of the early summer bills stating
that chlorine levels were going up in the next few months and that they did
NOT use chloramines. I considered that very thoughtful - must be some
homebrewers on the board.

smurman mentioned that an unseasonal chlorine jolt killed some of his fish.
There are better ways to test for chlorine! Simple kits are available at
aquarium stores and from companies like Hach Company (Loveleland, CO) which
specialize in water testing. A simple kit can be had from them for about
$12.50 which will test for total chlorine in a couple of minutes (Catalog
20604-00).

In the summertime assume chlorine is heavy and take steps to remove it.
Boiling, aeration and standing will remove free chlorine. Chloramines
require activated charcoal filtration. Call the water authority or buy a
test kit to see if you have chloramine (use a "total chlorine" kit and
thoroughly aerate or boil the sample after which any chlorine detected is
chloramine).

As for other water parameters: they are amazingly easy to test for these
days. Hach sells kits for $25 - 35 (each parameter) covering parameters
like alkalinity, hardness (calcium and magnesium), chloride, iron, sulfate
(not very sensitive, though), pH etc. The Cole Parmer catalog lists similar
kits by other manufacturers i.e. IME and Chemetrics (Calverton VA) which
has one of the easiest to use ideas out there. The chemistry is
pre-measured into evacuated ampoules. You suck up water until the color
changes and then read the parameter directly from a scale on the side of
the ampoule. No math! They have tests for alkalinity, chloride, hardness
etc and told me about a year ago that they are working on sulfate. Omega
Engineering appears to be selling Lamottes line of kits.

As you may have gathered I think the most important parameters are, in
order, pH, alkalinity, calcium hardness, magnesium hardness, chloride,
sulfate and chlorine. If you have a problem with iron or copper, add those
to the list. It's not that difficult (or expensive) to test for this group
of parameters yourself. After you've done it for a while you'll know what
the seasonal variations in your water supply are likely to be.

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

David Muzidal notes that his water is high in carbonates and low in
calcium. This is a recipe for high mash pH. Kolbach's residual alkalinity
is

RA = alkalinity - [ Calcium hardness/50000/3.5 + Magnesium Hardness/50000/7]

so that if calcium and magnesium are both low the RA will be close to the
water's alkalinity which, if it is high in carbonates, will be high. RA is
the alkalinity which the acid released by the malt cannot overcome so a
high RA means high pH, poor conversion and and environment which is not
ideal for yeast. Starters and media for culturing are often buffered to
pH's of 5 or less and yeast are happiest at these lower pH's where other
bugs are not very happy. Yeast nutrients often contain the phosphates of
amonia which have good buffering qualities (pH 7 buffer for calibrating
meters is a mixture of phosphates) and this is probably what's raising the
pH in your starter. Try adding a little phosphoric acid (1 drop at a time)
to get the starter pH down to around 5.

Adding gypsum will not lower the pH of a starter. It will lower the pH of
the mash, however, by upping the calcium in the RA formula and, thus,
lowering the RA. Its difficult to decrease the alkalinity of water with
lots of permanent hardness (low Ca, high HCO3). Dilution with very soft (or
even deionized) water is probably the most practical though the carbonate
can be removed by treatment with lime (see Hubert Hanghofer's post of
10/23).

A. J. deLange
 - Numquam in dubio, saepe in errore.

- --> --> --> To reply remove "nosp" from address. <-- <--



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---