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	FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
		Digest Janitor: pbabcock at hbd.org


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Contents:
  Sanke Parts ("MARTIN AMMON")
  Re: Achieving that typical British bitter character (Signalbox Brewery)
  hyperbole ? ("steve.alexander")
  Re: Cake-taking record anal CO2 tracking (John Schnupp)
  Change is constant... ("Pat Babcock")
  Science News article on beer (Bob Devine)
  Clinitest and fermentation, carbon dioxide measurements and fermentation ("Dave Burley")


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JANITORs on duty: Pat Babcock (pbabcock at hbd dot org), Jason Henning,
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Date: Sat, 10 Dec 2005 07:26:53 -0600
From: "MARTIN AMMON" <SURFSUPKS at KC.RR.COM>
Subject: Sanke Parts

Looking for sanke part the seal that goes into the spear at the check ball.  I
have seen only two different types because of the two different balls one being
a bearing and the other a stamped out piece.  Tried sabco no luck.

Kansas Swagman
Its Never Too Early Only Late




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Date: Sat, 10 Dec 2005 20:37:32 +0000
From: Signalbox Brewery <signalbox.brewery at ntlworld.com>
Subject: Re: Achieving that typical British bitter character

Dave Riedel observed:

 >but I do find that ales
 >from Conniston Bluebird Bitter, Fuller's London Pride, Blacksheep Bitter,
 >and the aforementioned Wychwood beer to Gale's HSB all share similar
 >attributes:  a dry, hoppy (but not resinous), almost tight flavour profile
 >commonly with what I perceive as a slight metallic edge, a balanced caramel
 >component and a noticeable, but fairly restrained hop aroma.  They are all
 >very enjoyable beers and they all seem to elude me as a brewer!

 >Does anyone have some advice on achieving the 'British bitter' character?

Pasteurise. I think that's what you are describing.
I believe that UK breweries are not so clean as North American ones
and pasteurise more heavily.

What you describe (and I don't doubt your observation of what you get 
over there)
is nothing like the Bluebird on sale at the brewery tap, which has an aroma of
hops on speed. It won a prize in the "Beauty of Hops" competition
(100% Challenger, by the way).

David Edge, Derby, UK



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Date: Sun, 11 Dec 2005 14:59:21 -0500
From: "steve.alexander" <-s at adelphia.net>
Subject: hyperbole ?

A recent posts caught my attention as defying common sense.
Dave Burley posts ...

<< Once the fermentation begins neither a hydrometer nor a
refractometer are any good [...] >>

Not so.  The Balling relationship for anaerobic fermentation allows us
to *estimate* the relationship between sugar used and ethanol & CO2
production and thus SG change.  Given OG & currentSG it's quite
possible to determine the amount of sugar used to within a few
percent.  There are published tables for brewing which allow some
detailed corrections (used for terminal alc%).

Also because the fermentable sugars that normally appear in all-malt
wort have a rather similar index of refraction and ethanol a rather
different one, it is also possible to come to a reasonably accurate
estimate of fermentation progress based on change of refractometer
readings (I assume ProMash does this calc).

Both estimates deteriorate the already limited accuracy of hydros and
refract's, and that's my point.

<< Clinitest is the only way to determine sugar content once
fermentation has begun [...] >>

Certainly not true.  Clinitest(a form of Fehling's test) is not the
only measure of wort/beer sugars.  Of course there are enzyme assays,
chromatographics techniques and several others.  Clinitest is a cheap
home test readily available.  It has several limitations which Dave
failed to mention.  Clinitest gives only 3 bits of resolution (only 8
color comparison panels), cannot be used by the color-blind, has
dubious accuracy in dark beers, measures the concentration of all
reducing ends, not just fermentable sugars, fails to measure any
non-reducing fermentable sugars (sucrose!).  Yes it is a a direct
measure of reducing-ends.  Despite the limitation it is useful in
determining an ESTIMATE of remaining fermentables in very late
fermentation.

On a suggested method - most, if not all diabetic blood glucose meters
measure only glucose via an enzymatic reaction.  You could use acid to
hydrolyze all(most) of the dextrins and sugars to glucose (and other
primary sugars).  This could be used as a relative measure of
fermentation progress.  Also note that these meters are not very
accurate nor repeatable as compared to the apparent resolution, and
the top/bottom range is quite limited.

 -S



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Date: Mon, 12 Dec 2005 00:13:23 -0800 (PST)
From: John Schnupp <johnschnupp at yahoo.com>
Subject: Re: Cake-taking record anal CO2 tracking

Ken Anderson <kapna at adelphia.net> said
>I might have to take the prize here.  I use an inexpensive
>(eBay) mass flow meter, and I love the thing.  It gives me a
>constant snapshot of the fermentation's progress.
<snip>
>Here's one of the resulting graphs, as an example:
>http://users.adelphia.net/~aken75/

I recall having a conversation with someone, maybe AJ, about the size MFM that
might be needed.  This was quite a while ago, quite possibly two years or more.

I'd be interested is knowing a little more about the equipment and how you have
it all connected.  Do you have any pictures on your page?







John Schnupp, N3CNL
(once in a) Blue Moon Hombrewery
[560.2, 68.6] Rennerian
Georgia, VT
95 XLH 1200



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Date: Mon, 12 Dec 2005 11:32:48 -0500
From: "Pat Babcock" <pbabcock at hbd.org>
Subject: Change is constant...

Greetings, Beerlings! Take me to your lager...

After wading daily through hundreds of SPAMs, trojans, and virus-laden 
emails in order to get to the few real posts and emails each day, I've 
decided that it is time to update the HBD mail handling systems to a 
more modern, more efficient architecture. Over the Christmas break, I 
will be implementing a new mail handling system to the HBD network. 
All mail will be handled external to the main HBD server, and absolutely 
every piece will be subjected to the rigors of virus and SPAM filtering.

This action may result in posts destined for the HBD being tossed out 
as SPAM as it "learns" the HBD environment - we will eventually overcome 
any such issues as we have with other filtering systems I've implemented 
over the years. I simply felt it important to let the subscribing 
community know what's coming. I will update you all on timing when I'm 
closer to installing the new servers. Hopefully you won't find out 
via an email outtage :o) 

All the best!

Pat Babcock
Chief Janitor
The Home Brew Digest
janitor at hbd.org



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Date: Mon, 12 Dec 2005 14:01:56 -0700
From: Bob Devine <devinebob at gmail.com>
Subject: Science News article on beer

>From the latest issue of Science News:

http://www.sciencenews.org/articles/20051203/bob8.asp

Bob Devine
http://www.frappr.com/hbd -- now has 250 homebrewer locations



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Date: Mon, 12 Dec 2005 19:15:23 -0500
From: "Dave Burley" <Dave_Burley at charter.net>
Subject: Clinitest and fermentation, carbon dioxide measurements and fermentation

Brewsters:

Bill Velek asks if any sugar test used for diabetics would work to evaluate 
the sugar content of a beer during fermentation.  The short answer is "no".

The long answer is that these modern tests are very specific to glucose ( 
which is relevant to diabetes)  and ignore other sugars, since most of these 
quick stick tests are based on a specific enzyme recovered from a fungus ( 
Aspergillus niger, I think) .

 In wort there are many kinds of sugars and each is consumed (or not) at a 
different rate and differently by various yeasts.

With a few minor exceptions noted below, the sugars fermentable by yeast are 
the reducing sugars like glucose, fructose and such.

So detecting just glucose would not do the job.

A less sophisticated ( but just the thing for us)  test procedure is one based 
on Fehling's/Bennett's  procedure of reacting a copper ion with sugar under 
alakaline conditions to produce an orange/brown, non-stoichiometric 
precipitate of various copper oxides/hydroxides.  The completeness of this 
reaction is measured colorimetrically by comparing the reaction solution color 
with a standard color blot. Your eye is able to distinguish thousands of 
shades so it is very accurate at estimating the amount of sugar in the sample 
by doing a direct comparison.   The color of this sample is derived from the 
mixture of blue of copper sulfate and the orange of the  copper oxides. Orange 
means all the copper is exhausted. Blue means none of the copper was 
exhausted( ergo no sugar) .  The various shades of green ( orange plus blue) 
in between tells you the amount of sugar in the sample when compared to the 
standard.

So you can extract 2 or 5 drops of fermenting wort and carry out a test in 30 
seconds with no concern for bubbles ( FAR more important than  the minute 
contribution of yeast) interfering with a reading.  You do not have to be 
concerned with temperature and best of all you are not imputing anything or 
using density of the solution as a surrogate for sugar content  You are 
measuring sugar <directly> in the presence of alcohol and carbon dioxide - 
and, yes, yeast - and not getting any interference.  If you want to use this 
test at higher than 2 or 5% sugar content all you have to do is prepare a 
sample by diluting the wort/beer by a known amount and put it through the test 
procedure. Then correct for your dilution.

There is a third problem with beer when compared to wine ( where the 
hydrometer procedure originated) and that is the solids in beer wort are not 
all fermentable unlike the majority of the solids in wine, so imputing the 
alcohol content is not a straightforward procedure unless you know exactly the 
% unfermentable solids.  Of course, we rarely do, if we are all grain and 
especially if we buy kits which may have varying amounts of sucrose added to 
the malt extract mixture. You can assume such a % unfermentable ( as these 
procedures do) but your results wll be off by some amount.

So what are the caveats in using Clinitest? Every test procedure has them.

 Not really very many if you understand a few things. In fact, these caveats 
are very useful in following the fermentation situation.

Clinitest will not indicate positive with pure sucrose ( your table sugar has 
a little fructose and glucose in it) so if you measure your wort with added or 
already there sucrose the response will not indicate the sucrose presence. Now 
<here> is the only place to use your hydrometer - no bubbles and no alcohol. 
If you pitch the yeast and then take a reading in a few hours you might find 
that the Clinitest reading is higher than after you first made up the wort 
with sucrose.. What has happened is that the invertase in the yeast has 
inverted the sucrose to fructose and dextrose ( glucose) to which the 
Clinitest is responsive.  Clinitest is not responsive to Lactose commonly used 
in making Milk Stout, so don't expect the reading to go up, except for the 
impurites of reducing sugars in the lactose.

Clinitest, however, is responsive to the reducing trisaccharides in the wort 
so these will give you a reading of 1/4% - 1/2 % at the "end" of the 
fermentation. If you are using a true lager yeast these will be consumed over 
the next few weeks of storage on the yeast in the secondary and you will find 
you will get a reading of 0% to 1/4 %, typically  This will not happen with 
ale yeast nor with ale yeast masquerading as lager yeast.  BTW when you get to 
these low values there is no problem with using all beer and no water in the 
test and correcting your readings.  This will double your ability to read 
these lower values. Of course, the hydrometer can not even come close to this 
accuracy.

So now where do you get this marvelous test? From your pharmacy ( they will 
have to order it) or beer/wine hobby store. You must specify the Clinitest 
KIT. It will come containing a testube, an eyedropper some reagent pills and a 
color chart. You just take say 5 drops of beer 5 drops of water in the 
testube,shake and drop in the pill wait 30 seconds for the reaction to finish, 
shake and compare the color of the testube with the color chart. You may have 
to go to 2 drops and 8 drops of water if the sugar content is out of range.

- ---------------------------
And now to using carbon dioxide emission as a measure of fermentation 
progress.

I am sure you have opened a bottle of beer ans asked youself  "Why doesn't 
this come to equilibrium with atmospheric pressure instantly by gushing out of 
the bottle?"  I am sure if you had a bottle with water and nitrogen or 
hydrogen and popped the top it would gush out. Or if you shook that beer 
bottle first it would come firing out and get your date all wet ( hey, maybe 
not such a bad ideas if she is wearing only a t-shirt). Now why would 
mechanical agitation do something if the equilibrium was just chemical in this 
case?  It's not.

The answer - clathrates - or that is the presumption. The carbon dioxide 
molecules are trapped in a close association of hydrogen bonded water 
molecules ( imagine a cage) .  Shaking has just about 5 kcals per mole of 
energy input and that is about the energy of formation of the clathrate. 
Shaking breaks up that clathrate. When you open that bottle - instant 
equilibrium with the atmosphere and maybe a wet date.

Now that I have Fredrik's attention. The carbon dioxide emission from a 
solution of carbon dioxide in water is dependent on the rate of breakup of 
these clathrates in equilibrium with the formation of these clathrates. If 
this is the slow step in this kinetic series, that is what you will be 
measuring, not the rate of formation of carbon dioxide. Therefore, your 
measurements do not represent the rate of formation of carbon dioxide from the 
fermentation. These reaction rates are, of course, temperature dependent, as 
is the saturation ( to which it is related) .

I suggest you follow the progress of the fermentation with Clinitest and 
compare it with your method of measuring the carbon dioxide bubbling out. And 
let us know your results.

Keep on Brewin'

Dave Burley



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