---

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


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Contents:
  Holy Hydrometers! ("Phil Yates")
  Re: hydrometers - bah humbug ! (Scott Alfter)
  Rennerian co-ordinates ("simon vogel")
  RE:  Tenacious Phenolic Issue ("steve.alexander")
  Re: looking for opinions (jeff)
  Bicentenary All Grain Brew... ("Cave, Jim")
  Responses to Phenolic Issue (Rick) Theiner <rickdude@tds.net>
  Chloramine removal by activated carbon filtration ("Wiscer")
  Multiple Batch Fermentation ("Doug Hurst")
  Make it stooopppp! ("Peed, John")
  Eating hops (David Edge)
  Are You a Penny Stox Player? ("Gloria William")
  Hydrometers ("A.J deLange")


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Date: Thu, 1 Dec 2005 18:06:05 +1100
From: "Phil Yates" <phil.yates at bigpond.com>
Subject: Holy Hydrometers!

>That post was powered by several+ glasses of Great Lakes Xmas ale, which
>goes down remarkably well for a 7.5%ABV beer.

Well then Steve, I take my hat off to you being able to supply all that 
information after several+ glasses of 7.5% beer. I wish I had have been at 
the party. Last experiment I conducted after "a few too many" was the urine 
samples in the schooner glasses to determine why I wasn't adding 
instantaneous weight during alcohol consumption. BTW, can anyone tell me how 
it is possible to drink so many glasses of beer in a certain space of time, 
as opposed to say just water?

>Next time I'll  use my advanced hydrometery knowledge and
>make a brine solution that will allow the tractor  to float when the
>tires are properly inflated.

Or you could come and have a look see how we do things here at Maple Downs. 
After 5 years of depilating drought, the skies have finally opened and she's 
giving us a drenching. I sit here on the porch with a beer watching my 
tractor float around in what only could be described as brine - this is a 
mixture of horse and cattle rear end deposits mixed in mud and heavily 
diluted.

>Is there supposed to be a point to all this ?   You must be a religious
>man Phil.

Yes my good man, there is a reason for all. Not that I've found it yet.
Now on the strength of that, I'm gunna go swill down yet another 
Schofferhofer Hefeweizen, and be back in time to see the tractor do yet 
another floating round of the ranch.

Phil 



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Date: Wed, 30 Nov 2005 23:13:24 -0800
From: Scott Alfter <scott at alfter.us>
Subject: Re: hydrometers - bah humbug !

Bob Tower wrote:
> Apart from investing in hundreds (thousands?) of US dollars worth of  
> testing equipment, is there a better way of collecting this data? Or  
> are we stuck with the hydrometer? Or was Steve merely warning us that  
> the readings we are taking are approximations, not dead on measurements?

I'm surprised nobody's mentioned refractometers yet.  They're cheaper
than you think (I bought mine from an eBay seller for ~$50 shipped, and
I've seen them as low as $35 shipped...it's mostly a matter of timing), and 
they need only a few drops of liquid to get a reading.

For beer, you want one that reads 0-32 deg. Brix, and has automatic
temperature compensation.  Once you verify a 0 deg. Brix reading with
distilled water (you can tweak it if necessary), you can pull a sample
at any stage of the brewing process, drop it on the business end of the
refractometer, and get a reading.  ProMash has a built-in utility
that'll determine true specific gravity from refractometer readings
taken at any point after the yeast is pitched, given an initial
(pre-pitching) reading.

Hydrometers are a cast-iron pain in the *ss to use.  I could never be
bothered to take regular readings with one.  The refractometer is so
much easier to use that it's no big deal to track gravity from pre-boil
to the keg.

   _/_  Scott Alfter
  / v \ Visit the SNAFU website today!
(IIGS( http://snafu.alfter.us/      Top-posting!
  \_^_/ rm -rf /bin/laden            >What's the most annoying thing on Usenet?



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Date: Thu, 01 Dec 2005 09:24:06 +0000
From: "simon vogel" <vogelsimon at hotmail.com>
Subject: Rennerian co-ordinates

Jeff's new address noted -does this mean we've all moved as well ?




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Date: Thu, 01 Dec 2005 06:18:51 -0500
From: "steve.alexander" <-s at adelphia.net>
Subject: RE:  Tenacious Phenolic Issue

RickT asks about his persistent phenolic flavor.

The strong vibrant chlorophenolic flavor does requires some source
of chlorine and that's either your water or your sanitizers.
Iodine has a uniquely medicinal flavor too, but I expect an old
hand like Rick Theiner can tell the difference.

You potentially could get some very funky flavored mold growth in
poorly stored malt and yes it could taste medicinal. I would expect
this flavor to be apparent in the sweet wort and not develop later.

Now other phenolic flavors can be derived from infection, for example
the clovey 4VG, as in weizens, is copiously produced by wild yeasts
and this can be perceived as medicinal or smokey too.  It's reported
that some Belgian ale yeasts will overproduce 4VG at higher
fermentation temps too.

Poor quality barley - feed barley for example, will give an
unmistakable "plant bitterness" phenolic character, but I don't think
you'd call it medicinal.

If it's that tingly chlorophenoloc flavor - look to your water and
rinsing procedures.   If you strongly suspect the malt, then I'd
expect this to be related to some surface mold infection and you
might detect it by simply ringing a few ounces of grain/malt and
tasting the rinse water.  The tongue may not give quantitative
results, but it's a damn fine instrument.

 -S






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Date: Thu, 1 Dec 2005 04:33:23 -0800 (PST)
From: jeff at henze.us
Subject: Re: looking for opinions

Paul:

> Then I let the carboy with the fresh wort sit for
> about 30mins to settle out cold break etc.

What is the purpose of letting the cold break settle for 30 minutes prior
to adding O2 to it? I've been just adding O2 as soon as I get done putting
the wort in primary - is there an advantage to waiting?

> My question, is this a crisis? can I get a complete
> fermentation? and what can I do to prevent a  an
> incomplete fermentation.

I wouldn't think it's going to be an issue that it took 2 days to get
started, so long as sanitation was good. Especially since it was a lager.
Can't tell you why it took that long to get rolling, but it's happened to
me with ales and the beer was just fine when it finished (and it did
finish where it should have).

- --Jeff
Canton, MI



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Date: Thu, 1 Dec 2005 07:27:19 -0800
From: "Cave, Jim" <Cave at psc.org>
Subject: Bicentenary All Grain Brew...

Yes, the 200th all grain brew is coming up!  I started brewing in 1977
when many of you were in diapers and I still have a 25 litre glass
carboy that was used for that first batch! My first all grain brew was
on March 28th, 1991 and I have brewed 197 since then.

I thought to commemorate this special event, that I would solicit the
HBD community to formulate the recipe for me. My 100th AGB was a Barley
wine--a somewhat disappointing effort. I would suggest that I would once
again brew a barley wine.  My yeast will be White Labs dry English ale.
I have the following ingredients:

Gambrinus ESB malt.
Special "B"
Chocolate Malt
Some sort of a British dark crystal malt
I have various lager malts, wheat malts and Munich malts, which wouldn't
seem to style.
East Kent Goldings Pellets
Styrian Goldings Pellets
Hersbrucker (saving this for a later pilsner)
Horizon Pellets (13.5% AA Base Bittering)
Northern Brewer Leaf (6.5% AA)
Don't have the alpha's handy on the EKG and SG hops, but I normally
shoot for a total IBU, and adjust the 1st addition accordingly to
account for the IBU's on the later additions.

I generally achieve about 85% efficiency (E.G. about 19.5 kg of Ale malt
achieves an OG of 1.050), and can mash up to 30 lbs fairly easily.
Maximum batch size is about 50 litres, but I expect that this brew will
be less. Normally I keg, but I will bottle this batch.  I don't have a
problem with using some small amount of malt extract or sugar to adjust
the gravity upwards. I will make a normal pale ale the week before and
use much of that yeast for the barley wine, so consideration of a
starter in unnecessary.

Go nuts Boys and Girls!
Jim Cave




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Date: Thu, 1 Dec 2005 10:12:05 -0600
From: Eric (Rick) Theiner <rickdude at tds.net>
Subject: Responses to Phenolic Issue

Thanks for all the comments on my question about phenolics.

It looks like the consensus is that it remains a sanitation 
issue, so that's what I'll address... new hose, disassembly of 
things that can be disassembled (and haven't been), and fierce 
cleaning of fermenters (maybe I'll try out that new thingy that
goes onto the end of your drill for scrubbing out carboys).

Rick




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Date: Thu, 1 Dec 2005 09:45:12 -0800
From: "Wiscer" <wiscer at hotmail.com>
Subject: Chloramine removal by activated carbon filtration

I've seen conflicting information on the degree that activated carbon 
filtration will remove chloramines from water.  I've seen reports that say 
that you can't remove chloramines unless you use campden tablets or go to 
the extreme of reverse osmosis filtration.  But I've also seen statements 
indicating that activated carbon filtration will remove the chloramines, 
sometimes this is with the caveat that you need a long contact time to have 
any significant effect.

Is there a definitive answer to this question?  If carbon filtration works, 
does the flow rate through the filter matter?  If slower is better, how slow 
are we talking here...should it take an hour to run 5 gallons through an 
activated carbon filter to remove the level of chloramines present at 
typical levels in my water?

What I have been doing is a very slow carbon filtration, essentially a light 
trickle out of the filter, such that it takes hours to fill the mash tun and 
HLT tank (for a 10 gallon batch).  Since I am doing this the day before I 
brew, it isn't much of a problem, but if such slow filtering doesn't remove 
more of the chloramines, then I'd like to shorten the process.  If filtering 
only removes a small amount of chloramines, then I would probably skip the 
filtration entirely since my water is otherwise excellent, nice and soft and 
able to be modified to approximate just about any water profile pretty 
easily (my thanks go out to the Sierrra Nevada and our water guys at the 
East Bay Municipal Utility District!)

Bill 


Return to table of contents


Date: Thu, 01 Dec 2005 13:28:04 -0600
From: "Doug Hurst" <dougbeer2000 at hotmail.com>
Subject: Multiple Batch Fermentation


Many commercial breweries use fermenters which are 2-5 times larger than 
their brewhouse capacity.  I feel the best reason for this is consistency.  
Blending multiple brewhouse batches will eliminate minor variations which 
have occured in the brewhouse.    Mega brewers often run somewhere around 5 
of their 10-14 daily batches into one fermenter.  Micros generally don't 
brew more than 2-5 batches per day.  I would guess the majority simply run a 
double brew day into one double capacity fermenter.  The general procedure 
is to pitch a large yeast mass with the first batch and aerate each time the 
fermenter is topped up.  Multi batching allows for increased economy because 
one larger fermenter costs less and uses less real estate than mutiple 
smaller ones.  Capacity vs cost is a major issue to the megas when they 
selling 36packs for $11.99.  Keep in mind they've  developed high gravity 
brewing to increase capacity with minimal capital outlay.


Doug Hurst
Chicago, IL
[197.5, 264.8] Apparent Rennerian




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Date: Thu, 1 Dec 2005 11:33:12 -0800
From: "Peed, John" <jpeed at elotouch.com>
Subject: Make it stooopppp!


Steve, I don't understand why you want to monitor the fermentation
progress continuously at all, let alone with great precision and
accuracy; it seems a very invasive activity to me.  I mean, one of the
first things a neophyte brewer should be told is, "Leave the beer alone
and let it ferment - don't risk introducing nasties into the
fermentation environment by checking the gravity every day.  Or even
every two or three days.  Just watch the bubble rate."  Little Beer Peep
101 - leave the yeast alone, they'll come home, leaving alcohol behind
them.

If I were trying to make a bajillion gallons of Budweiser every day, day
in and day out, then perhaps constant precise monitoring would be
important.  But for making a variety of first-class beer, beer that has
slight variabilities but is consistently excellent, I need to
concentrate more on things like procedure and sanitation and finding the
highest quality ingredients.  

I mean, I'm a driven brewer, but there are more important things to
worry about.  A hydrometer alerts you to major discrepancies so you can
correct them.  Cool the sample to a reasonable temp; spin the
hydrometer; bounce it off the bottom of the cylinder; wait until most
out-gassing has stopped; bounce and spin again; read the gravity and
temp; make a temp correction if necessary.  Are you two points off
pre-boil or post-boil?  Your beer will still be to style.  Maybe it's a
measurement error.  Who cares?  It just isn't that important.  

But monitoring continuously, with great precision?  That will tell you
that your fermentation is proceeding normally; so will counting seconds
between air lock bubbles.  Oh, I know that's imprecise, but that's the
whole point: Precision just doesn't matter in this case; it's the trend
that matters.  The beer is almost certainly going to ferment just fine
whether you monitor it or not.  And if you start and finish within two
points of your targets, think that's all the precision you need.

So no offense, but please, stop splitting hydrometer points and tell me
the best place you've found to get the highest quality malt and hops.

John Peed
Oak Ridge, TN





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Date: Thu, 01 Dec 2005 22:35:56 +0000
From: David Edge <david.j.edge at ntlworld.com>
Subject: Eating hops

Greg observed:

 > If anyone wanted to make some, it looks like hops is a
 >
 > part of Belgian cuisine...I haven't found any recipies
 > yet...

At the hop museum in Tettnang (DE), there's a hop season
menu from a Gasthof that is composed entirely of hop sprout
dishes.

They're coming into fashion in the UK at the ludicrous end of
the price spectrum, I suspect as hop producers look for ways
of dealing with the surplus.

David Edge



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Date: Fri, 02 Dec 2005 12:44:41 +0000
From: "Gloria William" <gwilliam_sk at charlottenc.nefn.com>
Subject: Are You a Penny Stox Player?

On the Rise Newsletter - November Issue, 2005

  In ths issue we are going to profile
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  A Huge PR marketing campaign has just started
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Company: Vinoble, Inc.
Symb0l: VNBL . OB
Recent_Price: $O.O55

2 Day Target_Price: .10
30 day Target_Price: .20

Trading_Alert issued for Fridays Trading!
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Read Why we believe VNBL will give big returns on
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About the company:

  Vinoble, Inc. is a holding company, which
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opportunity to build a successful business
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  The terror attacks on the United States on
September 11, 20O1 have changed the security
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specially in the banking, healthcare and
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* At this time much of VNBL's focus is on
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* VNBL is developing a form of RFID
technology which allows companies and
governments to wirelessly track their assets
and resources. Such technology has huge
potential in the protection and
transportation of materials designated "High
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* VNBL works on integration of the two afore
mentioned systems in order to create "High
Security Space" in locales where it is
deemed necessary.  Locations which may take
advantage of such systems are airports, sea
ports, mines, nuclear facilities, and more.

***N E W S***

9/6 Vinoble to Enter the Oil and Gas Sector

9/9 Vinoble Agrees to Acquire and Interest
in an Oil and Gas Prospect

10/13 Vinoble Finalizes Asset Acquisition

Latest News:

MALIBU, Calif.--(BUSINESS WIRE)--Nov. 17,
2005--Vinoble, Inc. announced today that it
has completed and executed a definitive
agreement in acquiring a minority interest
in the Oil and Gas Prospect known as the
Clovelly Prospect.  Since its discovery in
1950, the field has produced in excess of 30
MMBO (Mi||i0n barrels of oil) and 200 BCFG
(Bi||i0n cubic feet of gas).

In September, Vinoble disclosed to
shareholders its intent to enter the oil and
gas production industry by announcing that
it entered into a Memorandum of
Understanding whereby acquiring a minority
stake in the Clovelly Prospect.
Subsequently, the Company has complied with
the terms of the MOU and has finalized an
agreement for the investment.

While oil prices remain staggeringly high
and gold reaching an 18 year peak at over
$485 per ounce, the Company is excited about
entering two strong markets where demand is
high and additional supply is necessary to
satisfy the demand. ORX Resources, Inc., the
operator of the Clovelly Prospect expects
dry well production to begin in 4 to 6
weeks. Vinoble also expects to begin
conducting an exploration and 700 meter
drill program on the Hazard property in
early 2006.

  We believe that this is great news for
VNBL.  Just at the time when more domestic
oil operations are starting up, VNBL comes
in with a great product and solid
acquisition.

Put it on your radar now!!
** Act Early **
Please watch this one trade Friday and next week! 

   Go VNBL!!! 

____________________________________________________
Disc|aimer:
Informati0n within this emai| c0ntains "f0rward_l00king
st4tements" within the meaning of Sect10n 27A_of the
Secur1t1es_Act of 1933 and Sect10n 21B of the S3cur1t1es
Exch4nge Act of 1934. Any st4tements that express or
inv0|ve discussi0ns with respect to predicti0ns, g0als,
expectati0ns, be|iefs, p|ans, pr0jecti0ns, objectives
,assumptions or future events or performance are not
statements of hist0rical fact and may be "f0rw4rd
l00king statements."In compliance with Sect10n_17(b),
we disc|ose the p4yment of 25OO do||ars pri0r to the
pub|ication of this report. Be aware of an inherent
conflict of interest resulting from such p4yment. 



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Date: Fri, 02 Dec 2005 01:45:18 +0000
From: "A.J deLange" <ajdel at cox.net>
Subject: Hydrometers

The reason I missed the hydrometer commentary was because I never got 
#4897! So I just checked it out in the archives and I've got a couple of 
observations. First is, that as I have noted before, one must have a 
fairly good hydrometer (or preferrably narrow range set of hydrometers) 
take care of them (keep them clean, don't drop them) and use them 
properly which means insert them dry, wait for them to equilibrate 
(surface tension effects) and read them properly which means according 
to the manufacturer's instructions . The issue here is with respect to 
the meniscus: should the reading be taken at the top of the meniscus or 
by sighting across the surface of the liquid. In either case it is 
preferrable that the hydrometer be one made for brewing as these are 
calibrated for the surface tension of wort/beer not water. It is the 
position of the ASBC that readings "only slightly less precise" than 
those obtained with pycnometer or digital density meters can be obtained 
when hydrometers are of proper type and are properly used. They do not 
say what "slightly" means but do mention interlaboratory collabarative 
experiment error of around 0.00008 for digital density meters.

Steve mentioned a lot of factors which bear on the workings of 
hydrometers. A properly made hydrometer inserted in a sample at the 
proper temperature (ASBC wants attemperation to 0.1 C) should read the 
sugar content (Plato) or specific gravity. Clearly with sugar content 
(Plato scale hydrometer) there is no issue with repect to apparent/true 
nor with temperature (as long as the sample is at the proper temperature 
for the instrument). Ten percent sugar by weight is ten percent sugar by 
weight at any temperature. With a specific gravity scale true/apparent 
isn't much of an issue either as a true specific gravity of 1.040 
corresponds to an apparent gravity of 1.040048 (the Plato tables go out 
to 6 decimal places) but there is a problem in entering the ASBC tables 
(20C/20C) with a hydrometer calibrated for some other reference and 
measurement temperature. There are formulas for conversion (in fact the 
ASBC tables were converted from the (20C/4C) Plato tables. I was a 
little puzzled by Steve's comment about the Plato tables indicating that 
the SG of sucrose solutions do not change in proportion to pure water as 
temperature varies. AFAIK the only Plato table is the 20/4 one and that 
must have been enough of a WPA project with pycnometers and balances 
just by itself. Were there other measurements made at other 
temperatures? In any event the SG of sucrose solutions do change 
relative to water as a function of temperature - not by much, grant you 
but they do change.

I thought Steve's most interesting comment was about the potential for 
yeast to effect the hydrometer reading. As the hydrometer displaces 
yeast when it is lowered into the sample if the yeast have an effect it 
will be seen. Intuition says that as yeast are in suspension until they 
floc and then they either go up (top cropping) or down (bottom cropping) 
and take a fairly long time to do that they must have a density pretty 
close to that of beer. Furthermore, as a barrel of beer gives me only 
perhaps 600 ml of compacted yeast they are a small percentage (about 
0.5%) of the total volume and shouldn't have much effect.

I opined the other day that one ought to be able to easily acheive 0.2P 
accuracy with a hydrometer without taking too much care. I added to that 
the hypothesis that yeast shouldn't make much difference and, as I have 
a beer in the fermenter, figured that they wouldn't mind if I got into 
work a little late for the sake of brewing science. The beer is a fest 
which started out at about 14P and is now down in the 6's. I took a 
sample into a hydrometer jar and poured it back and forth several time 
to degass it and then lowered a 0-8P hydrometer into it (I don't do the 
rigorous cleaning protocol - just a rinse after each use). I put enough 
sample in the jar that the fluid displaced overflows the top (as the 
ASBC likes) and then read at the top of the meniscus (as I never got 
instructions with these hydrometers I don't know if that's the right way 
or not but it is the way I've always done it with these hydrometers). I 
read 6.2P. Then up to the lab where I centrifuged a portion of the 
sample and ran the rest straight through a density meter. I got three 
identical readings of 6.33 P corresponding to SG of 1.02497. For the 
centrifuged sample I got 3 readings of 6.26P for an average SG of 
1.02470 (SD .000005). Conclusions: Accuracy of better than 0.2P easily 
acheived and I should read at the bottom of the meniscus. If I do so I 
should be within 0.1P (.0004SG). The presence of yeast made a difference 
of 0.07P corresponding to 0.00027SG (note that the ASBC requires that 
samples that are not bright be filtered before measurement). For precise 
work yeast should be removed.

Now as we are all good scientists here we need to recognize that this is 
a single experiment at one level of gravity on one beer etc. and not go 
publishing far and wide that hydrometers are as good as densitometers 
(which they weren't in this experiment anyway) but we do have at least 
one data point that shows that maybe we should look at our hydrometers 
in a somewhat more favorable light.

Finally let's observe that if we start with 10P wort and have a standard 
deviation of 0.1P in our hydrometer readings that the standard deviation 
in an ADF calculated from a pair of hydrometer readings is 1.4%. Thus 
ADF from such readings is easily the measure of fermentation that Steve 
seeks; good to almos 2 significant digits.


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