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HOMEBREW Digest #2754
HOMEBREW Digest #2754 Tue 30 June 1998
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: Roller Mill Spacings (again) ("Ludwig's")
Winemaking (Tom Clark)
TEC cooler (Poris)
Hops variety/miscellany (Joseph.M.Labeck@brew.oeonline.com, "Jr.")
Industrial .vs. medical O2 ("Hans E. Hansen")
Misc questions & comments ("Hans E. Hansen")
RIMS Heat exchanger (ZIMURGIST)
RE: Charlie P. Scandal (Doug Kerfoot)
Keg fittings, Open Ferment (droot)
Open sea Fermenting ("Jerry Holcomb")
Dry Tripels (Tom Wolf)
alternative for casks? (Tom Alaerts)
Is 212 F steam hotter than 212 F water? (william macher)
Roller Mill Spacings (again) (Jack Schmidling)
salt (Paul Mahoney)
RE:Oxygenation (NEWTRADBC)
Color I (AJ)
Color II (AJ)
Dry Beer (Kyle Druey)
RIMS Does Not Require a Thin Mash (Kyle Druey)
End of my career as a brewer? ("Michael Kowalczyk")
re: Citric beer (John_E_Schnupp)
Have you entered a MCAB qualifier yet?
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----------------------------------------------------------------------
Date: Sat, 27 Jun 1998 00:05:08 -0400
From: "Ludwig's" <dludwig@us.hsanet.net>
Subject: Re: Roller Mill Spacings (again)
Ok John,
now you've gone and made me secure my beer, get out'a my chair and get
this info for you. You owe me dude.;) First off, I'm using a roller
mill with two counter-rotating, 3 inch dia, 8 inch long, smooth,
concrete rollers. Only grain I've milled is Briess 2-row and my best
setting is about 0.032 in roller spacing. My mill design allows
adjustment on the fly so I've played around with it pretty much every
time I do a batch. This spacing gives the best results. Not sure how
this spacing would work with those mills with skinny/narly rollers.
Dave Ludwig
Flat Iron Brewery
SO Md
------------------------------
Date: Sat, 27 Jun 1998 07:50:41 -0400
From: Tom Clark <rtclark@eurekanet.com>
Subject: Winemaking
Does anyone out there know of a forum similar to HBD that deals with
the art of making your own wine?
Is there significant risk in using my beer making equipment to make
wine? Will it still be OK for making beer?
Many thanks
E-Mail welcome...
Tom Clark
------------------------------
Date: Sat, 27 Jun 1998 11:16:15 EDT
From: Poris@aol.com
Subject: TEC cooler
Thanks for all the input on my idea for a TEC fermentation
controller/cooler. The consensus was that their performance is marginal for
this application and the expense was excessive compared to used refrigerators.
I tried to avoid using a large, heavy refrigerator in the basement (my
basement is down a hill) but maybe this is the best compromise. Maybe a TEC
1 cubic foot yeast starter or a single 12 oz bottle controller :)
Thanks,
Jaime (finally warming up in the Santa Cruz Mountains)
------------------------------
Date: Sat, 27 Jun 1998 12:2:59 +0800
From: Joseph.M.Labeck@brew.oeonline.com, "Jr." <joe-sysop@cyberbury.net>
Subject: Hops variety/miscellany
(Let's see if I can get this right)
I come before the gods of Homebrewing on bended knee,
a most unworthy extract brewer, to place my ignorant
question on the altar of the HBD.
(Gosh, I feel like I'm writing to the Usenet Oracle.)
Anyway, sometime ago I had posted with a few questions.
Most of them were taken care of, but this got lost in the shuffle.
I had ordered some hops from a mail order garden supply shop.
When I asked them the variety, they replied "Oregon Golden
Nugget". Anyone faniliar with this? Private e-mail fine.
On another issue, I've been reading the Digest faithfully for
about 5 years. George, George, Al, Rob, Dave, and many others,
have all been very helpful, and patient. I got a lot of information
I needed when I was very new at this. I still get a lot. Although I
have no all-grain ambitions, I find it interesting to know what
goes on in the mash.
Some stuff bores me, but I'm told I do, too.
One last thing:
Sam Mize writes---
>Personally, I'd say if it's brewed at home and not for sale,
>it's homebrew. That's a definition that some contests have used,
>to allow for the private
>work of professional guys like Jethro and George Fix. However,
>this does put a small homebrewer at a disadvantage compared to
>someone with analytical lab equipment and professional experience.
I'm curious...Why would I be at such a disadvantage, just because
I'm only 5'5" and 115 lbs?
Hmmm, that twice I've posted in the same year. How many more
before I'm a "regular".
Joseph M. Labeck, Jr.
Joe's Beer - Featuring Cuppa Joe Stout, Nut "n" Tuit Brown Ale,
Nothing Special Bitters, Uncle Bill's Porter, and Born To Be Mild Ale
------------------------------
Date: Sat, 27 Jun 1998 10:10:36 -0700
From: "Hans E. Hansen" <hansh@teleport.com>
Subject: Industrial .vs. medical O2
Al K. wrote:
Same oxygen. The only difference between medical grade and industrial
grade oxygen is that you need to drag around a stack of paperwork on
the tank that *holds* the oxygen in the case of medical O2. I've read
(here in HBD) even that some medical oxygen has anti-fungal agents
added, but have not seen it confirmed by anyone. If that is indeed
true, medical grade would be worse.
<end quote>
A medical O2 salesman once told me that industrial (i.e. welding)
O2 is actually more pure than medical. He said that the medical
grade can give spots in welds (carbon?). Obviously, whatever
impurities are in medical grade must be in minute quantities and
harmless to both us and, most likely, yeast. Anti-fungal agents
would be a different matter, tho.
A few sniffs of the O2 from the welding setup sure helps a
hangover (not that I would know). Just be sure to turn off
the acetylene.
Hans E. Hansen
hansh@teleport.com
------------------------------
Date: Sat, 27 Jun 1998 10:57:16 -0700
From: "Hans E. Hansen" <hansh@teleport.com>
Subject: Misc questions & comments
A couple of questions and a comment:
1. I have recently went to grain brewing and am having a
difficult time acheiving the proper mash temp. The specifics:
5 gallon Rubbermaid cooler, small batches using ~4 lbs or so
grain. Using a single infusion of 1.25 qts/lb, Brewers Workshop
software says to use 172 deg water to achieve a 158 deg mash
(you'll see why I use such a high temp in a minute.). Also note
that I have to use an extra qt because of the Phalse bottom.
When I do this and mix, I end up in the low 140's. Two more
quarts of boiling water are needed to get me up to the low/mid
150's. It appears that I need strike water at around 180 or
so to do it right the first time. What gives? (p.s. - I have
checked the thermometer.)
2. Sparging and HSA - Is HSA a concern when using Phill's
Sparging Sprinkler? It looks like this aerates the sparge
water a lot. Also, I have to use ~200 deg sparge water to
acheive 170 going into the cooler because the sprinkling action
cools the water A LOT.
===============================================================
Comment:
A few weeks ago there was some talk about homemade
crystal malt. I tried it and have a few notes of possible
interest. Nothing original here, these thoughts were expressed
by others in the original posts. Sorry that I have lost the
names of the originators.
1. Try it. It's really quite easy.
2. I found it nearly impossible to achieve adequate temperature
control in the oven for the mashing stage. If I set my oven
to 140 deg, it would turn on at 140 and heat to about 190 before
it would turn off. Then slow cool to 140, repeat. Someone
suggested a CrockPot. Good idea. I set mine on low. After
an hour or so, it was at 160 deg. I turned it off and let it
sit for another hour where it fell to the high 140's. I felt
this was probably adequate.
3. Don't roast at too high a temperature. I was in a hurry
and turned up the oven to 300 deg to dry/roast. The grains
around the edges of the cookie sheet got quite dark, the ones
in the center stayed much lighter. i.e. - not consistant.
I think a slow roast in the low 200's with occasional stirring
would work fine.
4. Getting consistent results (concerning color) should be
obtainable with simple experimentation. Keep quantities,
equipment, and temps the same, and just vary roasting time.
5. Results? My Ordinary Bitter currently has 1" of foam on
it, so I can't speak about flavor.
Hans E. Hansen
hansh@teleport.com
------------------------------
Date: Sat, 27 Jun 1998 16:58:26 EDT
From: ZIMURGIST@aol.com
Subject: RIMS Heat exchanger
Greetings to the collective,
I've read much concerning RIMS heating elements, etc while lurking recently.
I've used a RIMS sytem with electrical element for about 5 years. I've tried a
3800, 4500 and 6000 watt LHD element. I think RIMS is great for 5 gallonb
batches, but when using grain bills of 20# or greater, I found the element
unable to make the next temp boost in a reasonable time frame. I thought about
using an external heat source, but did not due to concerns about scorching. I
ran across a RIMS website that used a heat exchanger made of 1/2" Cu coil
inside the sparge vessel.This seemed to make sense as some home heating
systems utilize the H2O heater to run water through a coil which the furnace
forces air over. To make along story short I retrofitted my converted keg
system to include a 20' Cu coil in my sparge tank. I mash with 1.5 qts/lb of
grain and have no problems with complete conversions @150F for 60". Temp
boosts are fairly rapid with 170F H20 in the sparge tank (135->150 in 5-7") I
used1/2 comp-1/2 MNPTss Swagelok fittings with ss washers and teflon
string(5/32 faucet packing available at any hardware store) on the inside
screwed into a 1/2 ss ballvalve on the out side. Teflon is good to +400 F
according to the label.
The website that was my inspiration is www.pressenter.com/~rcalley
On a different note- has anyone tried a small fermentation with lactobaccillus
to be pasteurized and added to a Belgian wit for acidity/tang? I saw a posting
in the archives for some sour mashing procedures using yogurt, grain or
sourdough starter, but as I understand any acid tangy adjustment must be post
boil. I've thought inocculating a batch after fermentation and monitoring it's
acidity then flash pasteurizing by immersing a corny keg in 160-170F H2O to
stop bacterial action. Anyone been daring(crazy) enough to try this?
Cheers,
David Schmidthuber
Zimurgist@aol.com
------------------------------
Date: Sat, 27 Jun 1998 18:07:14 -0400
From: Doug Kerfoot <dkerfoot@macatawa.org>
Subject: RE: Charlie P. Scandal
Rick Theiner wrote:
>Shocking stuff!! There is truly an amazing likeness, and I wouldn't
put
>it past Charlie P., but there seems to be a subtle difference that I
>can't put my finger on.
>You've got some frightening pictures, Doug (but fun!).
Thanks Rick, I will make the assumption that the frightening pictures
you mention do not include the times that my face has been on the beer
cam! ;)
Does anyone have any ideas for the beer cam? I mean now that I have
one, I should try to find a use for it, eh? To date all it has proved
useful for is to allow me to observe how bloodshot my eyes get by my
third glass of Pils. Well, that and to provide free advertising for the
Unibroue folks. It was suggested that an air-lock cam would be more
entertaining than a fish cam. I agree and will probably point it at a
carboy this winter, but I really don't want to stick the cam in my
fridge and don't want to drink a beer fermented at 85 F! (Now, the cam
in the fridge would answer the age old question though, wouldn't it?)
-Doug
http://www.macatawa.org/~dkerfoot/
------------------------------
Date: Sat, 27 Jun 1998 16:51:17 -0400
From: droot@concentric.net
Subject: Keg fittings, Open Ferment
I am a welder, and I do play one at work (sometimes). I do
not use a welded fitting on my converted kegs. I use plain Pipe
fittings. I just buy a 1/2" ball valve with a male thread 3/8 pipe,
and some flat washers. I try washers on the male pipe threads
until I find one that fits. Metric flat washers fit better than
American. I then use a female pipe thread/compression fitting
on the inside. The washers take up the space, and sandwich the
thin stainless keg in between them. This makes cleaning a
breeze, because it can e taken apart at any time. I then
can install any type of copper tubing that I prefer on the end.
I use a piece of 3/8 copper tubing bent like a ? for my mash tun
manifold. I use a short piece of plain copper tubing (3/8) for my
boil kettle. I use a 90 dagree elbow for my HLT, pointed down.
Open Fermentation.
I use it. I ferment in an open converted sanke keg. I usually
Use Wyeast 1007 German ale yeast. The cooled wort is drained
Into the keg, and the LARGE starter is pitched into the wort.
I ferment in my basement for about 6 days. I then drain the
BEER out from under the yeast. The yeast is still in the fermenter
In a pancake on top of the beer so it stays on top and does not
End up in the corny keg. Never an infection, and always great
Homebrew.
By the way, A Plasma cutter is the only way to cut the top
Out of a sanke keg. Anyone in the Lockport Area, I will cut
them for a homebrew or two.
Email if you have any questions.
------------------------------
Date: Sat, 27 Jun 1998 20:34:36 -0700
From: "Jerry Holcomb" <eagle@teleport.com>
Subject: Open sea Fermenting
>Here is one I doubt anyone has seen on the HBD before.
>A friend of mine plans on living on a yacht once he retires. He
questioned
>me about the
>possibility of brewing on his boat.
**SNIP**
The use of a corny keg with a pressure valve set low (say 5lbs) should do
the trick just make sure that it is firmly secured to the boat. Don't need a
heavy tank slamming around a pitching boat.
------------------------------
Date: Sat, 27 Jun 1998 20:39:05 -0600
From: Tom Wolf <wolfhrt@ibm.net>
Subject: Dry Tripels
Some more discussion:
Al K don't take offense to my style I am a slow typer and this style
without the long lead in moves fast.
I would love to learn more about this subject!
Al writes: "Firstly, I don't think that Tripels are dry. I think they
are medium sweet."
Yiikes! It looks like I have to do some more Liquid research starting
with a Westmalle trippel. I have had this same discusion with other
revered brewers and got the "It was the liquid bread ,therefore it is
supposed to be sweet" answer. My judgement is that the homebrew and
microbrew tripels tend to be overly sweet but that best Belgian examples
have a much more balenced dryness.
Al writes: "Secondly, I don't agree that the yeast will necessarily be
"ruined" by the additional sugar."
Yeasts that have fermented a wort of gravity much past 1.068 are pretty
much 'toast' from the standpoint of pitching into a new beer of any
strength. I would imagine that they would have a problem of finishing a
1.080 wort. I think that pitching lots of yeast is just moving farther
out on a log curve of attenuation capabilities. The returns are
diminishing and it takes a ton of yeast!
Al's Three words: "alcohol is sweet."
I say the opposite. Alcohol is drying. Try adding Everclear to an
overhopped malty sweet IPA. It will be drier and more alcoholic. Not
sweeter.
I will try this experiment as I have both of the ingrediants.
Cheers all!
------------------------------
Date: Sun, 28 Jun 1998 14:57:29 +0200
From: Tom Alaerts <TomA@BUT.BE>
Subject: alternative for casks?
Hello gurus,
You guys have been a lot of help for me already. I am sure my brews will
reflect this! Here's yet another question:
It is sometimes suggested to let some kinds of beer mature in wooden
casks. For example, commercial Old Flemish Browns are very often aged
this way. But I don't have a cask. So I thought, maybe I could just put
a lot of "wood-spirals" (don't know the correct English word) in my
plastic secondary fermenter. So I have a big surface of wood that's in
contact with the fluid. I thought of this because the Californian
Monterey Vineyard (owned by Coca Cola, I believe) uses a similar
processus (while in France, it is a forbidden practice if you want a
"Grand Cru blabla" nomination).
In short, is this a good idea?
Cheers,
Tom Alaerts
------------------------------
Date: Sun, 28 Jun 1998 08:56:44
From: william macher <macher@telerama.lm.com>
Subject: Is 212 F steam hotter than 212 F water?
Hi Dave and all,
Just read Dave's ["Ludwig's" <dludwig@us.hsanet.net>] reply to my RIMS
heating element sufrace temperature HBD question...
A Sunday HBD is always a great surprise!
Dave, I am certain what you stated about the surface temp of an electrical
heating element vs flow rate is true. I was trying to get a reference temp
for an element in a rims that was operating successfully/properly, to use
as a base line for comparing to the temperatures that would be encountered
with steam injection, as I think lower temperatures of steam is one of its
chief advantages.
>Also, the more I think about the steam idea. Is there any significant
>advantage to injecting say a lb of steam at 215 deg and a lb of water at
>212 deg?
Yes. THere is a tremendous difference. I was so amazed by this fact that I
decided to post what I learned to the hbd, and it turned out to be a
three-part posting on the basics. I hope it conveys the necessary
information. To make a long story short, when a pound of steam condenses
and produces a pound of 212F water, during the phase change from vapor to
liquid, that steam gives off amount of heat energy equal to six times the
amount of heat required to heat a pound (pint) of water from 32F to 212F.
That is a LOT of heat energy. So, the difference between steam and hot
water at 212 F is tremendous!
> If your injecting the steam through a nozzle in to the flow,
>soon as it hits the flow, it will just be a dribble of hot water and
>would take a lot of steam to heat effectively.
Actually, your are correct in the first part. Steam on a weight basis,
occupies 1600 times the volume of water. So a bubble of steam becomes
1/1600 of its size when it condenses and releases its heat content. The
fact that it becomes a dribble, is to our advantage if we use it to heat a
mash, for example. When it is all over, we do not really add that much
condensate to the mash, considering the amount of heat that is carried to
the mash by the steam.
The second part of your sentence needs some clarification. Steam gives of
tremendous energy when it condenses into water.
Bottom line is it would take a lot of hot water to heat effectively, but
not a lot of steam, since the transition(phase change) from steam to
liquid is where we get most of the heat from.
Suppose one were doing a simple infusion mash, and raising temp from say
155F to 167 F. If we had to choose between Steam and 212F water, we would
find that it would take much, much more water( than steam, by weight) to
accomplish this temperature rise.
[A quick mental calculation tells me it would be about 90 times more
water...of course, take this with a cup of salt...err...grain of
salt?...I've just had one cup of coffee this morning :-)]
Oh...back to the subject line...
No, 212 F steam is not hotter than 212 F water. It just carries a much
higher energy content, and when it condenses and gives off this energy, it
becomes 212 F water!
Amazing stuff, this steam, isn't it?
Bill
Bill Macher macher@telerama.lm.com Pittsburgh, PA USA
------------------------------
Date: Sun, 28 Jun 1998 07:37:06 -0700
From: Jack Schmidling <arf@mc.net>
Subject: Roller Mill Spacings (again)
montgomery_john@ccmail.ncsc.navy.mil says:
" I got ONE response (thank you Kyle Druey) to my question the other
day regarding recommended roller spacing for different grains
(barley vs. wheat vs...) using adjustable mills.
Perhaps that says something about the crush mythology and more
importantly, why our fixed mill is so popular with the grass roots
homebrewers.
"Does anyone know of a resource on the Internet?
I've searched Real Beer and The Brewery.
You need to search a "real" resource.... there has been an application
note on "Crush Quality" on our web page for years.
js
- --
Visit our WEB pages:
Beer Stuff......... http://ays.net/jsp
Astronomy....... http://user.mc.net/arf
ASTROPHOTO OF THE WEEK..... New Every Monday
------------------------------
Date: Sun, 28 Jun 1998 13:45:41 -0400
From: Paul Mahoney <pmmaho@roanoke.infi.net>
Subject: salt
This is a request for a discussion on the use of salt in our homebrew.
The June 27, 1998 issue of "The Economist" included an article(p. 88)on the
production of malt whisky in Scotland. It reported that malt contains
hundreds of individual components - alchohols, esters, acids, and phenols.
All of the things we have come to know and love!
I found the following quote interesting: "Scientists at the Scotch
Whisky Institute in Edinburgh have experimented with adding salt to blended
whisky barrels to make the spirit mature faster (having millions of barrels
lying around for at least three years is the industry's biggest single cost).
Not only did salt speed things up, its boosters say it enhanced the flavor,
making blends more malty."
I then checked S. Snyder's "The Brewmaster's Bible" (p. 84-85), and he said
that the addition of Na contibutes body, full mouthfeel, and character.
The addition of Cl brings out malt seetness and contributes to mothfeel and
complexity. Too much Na will give a "seawater" taste.
So how many of us add a pinch or one teaspoon of table salt to our wort?
Will salt speed up our processes? Who does it, and does it improve your beer?
Do you recommend it?
Paul Mahoney
Roanoke, Va.
------------------------------
Date: Sun, 28 Jun 1998 15:07:32 EDT
From: NEWTRADBC@aol.com
Subject: RE:Oxygenation
<From Tom Bergman as newtradbc@aol.com>
I began using oxygen this year, and although I did not do a scientifically
valid test, the results have been impressive in terms of quickness of
fermentation and achieving final gravity. I noticed no visible consistent
reduction in lag time (sometimes less, sometimes more), but I typically pitch
a fair amount of yeast slurry (1-2L starter for ales, 3-4L starter for
lagers). One particularly impressive example was a barleywine, used slurry
from a 5L starter (which I make and pressure can myself if we want to restart
the botulism thread!) with Wyeast 1056, and 3 minutes of oxygenation.
Barleywine dropped from 1.106 to 1.022 in less than 7 days, and was reasonable
bright and surprisingly smooth tasting for a one week old barleywine. Normal
gravity beers tend to reach final gravities in 3 to 4 days, lagers sometimes a
week. So I'd recommend it. I typically use 2 minutes of steady stream of
oxygen per 5 gallon batch, done prior to pitching yeast.
I have a friend in the compressed and liquified gas business, and she said
there is a difference between medical and welding oxygen (in addition to the
paperwork). Welding oxygen is not as pure (like 99% oxygen), but the
impurities are other gases, principally nitrogen. There is NO contaminant
like oil (because it would turn the oxygen bottle into a bomb). She suggested
only getting welding oxygen since its much cheaper and the 1% other gas
content is irrelevant to the homebrewing application.
------------------------------
Date: Sun, 28 Jun 1998 19:34:01 -0400
From: AJ <ajdel@mindspring.com>
Subject: Color I
I don't recall exactly what I wrote about superiority or inferiority of
various methods for measuring/describing/quantifying beer color but I
didn't mean to boost or deflate any particular one - rather simply to
note that there is no intepretation, judgement, fatigue or perception
factor with the ASBC method or any other method based on
spectrophotometry. Compare with the Lovibond system which requires, as I
understand it, a visual comparison with standard glasses. The ASBC
method (absorbance in a 1" cell at 430 subject to the turbidity check)
is the ASBC's method, not mine. I'm sure that it is the result of much
study (ASBC Report of the Subcommittee on Color in Beer, Proc. 1950 p
193 and ditto, Proc 1972 p140 are cited in the MOA - I've seen neither
of these) and represents the best compromize in terms of quantifying
beer color by a single number: a thing to be devoutly wished! I don't
think it's perfect and neither, I'm sure, does the ASBC. Color is very
much a subjective thing. Different folks perceive color quite
differently from one other. I am an obvious and extreme example being
color blind. At the other end of the spectrum, some people are known for
having an "eye for color". In the remainder of the post let's look at
how good the ASBC method is in terms of what I found in my refrigerator
this Sunday afternoon.
First, a little background to help you interpret the data. Lots and lots
of work has been done in quantifying color. Without this color
television would be impossible. The job of a tv camera is to measure the
color of a pixel and transmit that data to the receiver. The receiver
has to take the camera's measurements and produce light _that looks to
the viewer like the object being televised_. The TV set doesn't exactly
reproduce the spectrum of light picked up by the camera. It puts out
light that makes you perceive as being the same color as if you were in
the studio.
The result of much cooperation between psychologists and engineers is
the tristimulus response model of color based on the three sets of color
receptors in our eyes. The model includes the response of each of these
three receptors to light of various wavelengths for an average person
and, based upon an average person's response quantifies color into three
numbers. These numbers can be transformed into various coordinate
systems depending upon the application (i.e. to encode them for
transmission) but for specifying the color of beer (or any other liquid)
luminance (brightness) symbolized by Y and a pair of numbers (x,y)
between 0 and 1 which convey "chrominance" or color information are
used. This system has other applications as well. The x and y numbers
by themselves don't mean much but the distance of an (x,y) point from
the point (x=0.32,y=0.32) gives an idea of the "purity" or "saturation"
of a color and the angle of a the with respect to the positive x axis
gives the "predominant wavelength" or "hue".
With beer, the tristimulus responses (X, Y, Z) can be obtained by
measuring the light which comes through the beer using tristimulus
filters in a colorimeter of, if a spectrophotometer is used, by summing
the transmissions in percent (_not_ log units) at 30 wavelengths (a
different set of 30 for each of the three filters) and scaling the sums
to produce X, Y, and Z. x and y are then simply
x = X/(X + Y + Z) and y = Y/( X + Y + Z)
(x,y) values are plotted on a so called chromaticity diagram from which
the predominant wave length or hue can be read as can the saturation or
purity of the color. This can, of course, also be done mathemtically.
Thus what you will see, assuming you are an average person who fits the
tristimulus model well, can be modeled by a set of three numbers:
(Y,x,y) or (Y, predominant wavelength and purity). The latter set is
more descriptive.
So lets look at some beer. In the table which follows the beers are
1 and 2 Home brewed Bohemian Pils (yes, I know they are too dark but
the judges haven't caught this yet!)
3 Homebrewed Bavarian Weizen
4 Potomac Mount Vernon Porter
5 New Castle Brown Ale
6 Prima (Victory's Saaz tea).
These certainly don't represent the universe of beer but, as they are as
random as what's in my fridge at any given time they can't be said to be
a biased sample either.
WRT the table columns: SRM is self explanatory, Y* is -10log(Y) and I'm
displaying the data this way simply because SRM is -10log(transmission)
though SRM is measured in an inch and Y in a cm. This is important as we
shall see. x and y are the chrominance coordinates, Sat is the percent
saturation of the color. 100% means a pure color. l_dom is the dominant
wavelength (i.e. the hue) and Color is a description in words which
covers a range of predominant wavelengths.
Beer SRM Y* x y Sat l_dom Color
1 13.8 1.79 .426 .434 63% 577nm Yellow
2 14.5 1.91 .427 .437 63% 575 Yellow
3 4.3 0.63 .349 .365 22% 577 Yellow
4 42.9 7.15 .558 .427 95% 588 Orange
5 25.7 4.29 .496 .446 85% 582 Yel-Or
6 5.0 0.66 .354 .372 27% 576 Yellow
-More-
------------------------------
Date: Sun, 28 Jun 1998 19:36:57 -0400
From: AJ <ajdel@mindspring.com>
Subject: Color II
The first thing we see from these data is that the beers analyzed are,
though they vary in color from the very pale wheat beer at 4.3 to the
quite dark porter at 42.9 SRM all very close to the same color. The
color spectrum from violet to red (400 to 700 nm dominant wavelength)
encircles about 230 degrees on the chromaticity diagram. This set of
beers in found in a wedge that is 9 degrees wide. Thus we are tempted to
say "all beer is the same color it's just that some are darker than
others" and simply measure the "darkness". This is the basis for the
ASBC measurement. If we look at the Y* data for the beers analyzed and
compare to the SRM values we find SRM = 2.43 + 5.68*Y* to a very good
approximation (r = .997). I don't know for a fact but would venture a
guess that the Subcommittee on Color in Beer took transmission data on
lots of beers and did linear regressions of log luminance vs absorbance
at several wavelengths. I'll further bet that 430 nm gave the best fit.
This suspicion is confirmed by looking at the absorbtion spectra for
beer. There is no peak at 430 nm so why use this particular wavelength?.
Now of course there will be beers that fall outside this 9 degree wedge
and those are, of course, the one's that George is talking about. A
person with normal color vision can see the difference in color between
beers even over the 9 degree range provided the color is reasonably
saturated and, of course, saturation is ignored when the SRM method is
used. Thus even with unusual cases aside the SRM method has its
limitations. The bottom line here, assuming that the goodness of fit
between log Y and SRM would be upheld with hundreds of beers instead of
just 6 I've measured is: _specifying beer color with SRM and
distinguishing beers based on this method is akin to distinguishing beer
color as observed on a black-and white TV set_. Now that's OK. I used to
watch black and white TV a lot when I was a kid. Luminance contains most
of the information (the luminance signal in a color transmission is
conveyed with lots more bandwidth that the chrominance, many lower
animals have luminance perception only).
Now one of the most interesting little discoveries of my investigations
this afternoon is that perceived color (that's what x and y tell you
about) depends on the depth of the beer being looked at. I took all data
with a 1 cm cell but it's very easy to calculate what the transmission
is at any other cell length. Here's some data on the New Castle Brown
Ale for other path lengths:
Path Y* x y Sat l_dom Color
1 cm 4.19 .496 .446 85% 582 Yel - Or
2 cm 7.63 .570 .420 100% 591 Orange
3 cm 10.63 .610 .388 100% 596 Orange
4 cm 13.32 .637 .362 100% 605 Or-Red
The fascinating conclusion from this is that the wider the glass
through which you look at NCBA is the redder it looks! My wife with
normal color vision confirms this - with a little prompting. Note also
that the log luminance does not increase at the same rate as the SRM
metric. Thus if we did go to specification of beer color using the
tristimulus model we'd have to specify the cell depth as well. This is
in fact done when using this model for, for example, reporting the color
of water samples.
Summary:
- Perceived beer color is communicated by 3 numbers (Note: a Taylor
series expansion is perhaps more applicable than a Fourier series
expasion as a means of describing the whole absorbtion spectrum but
would require about a dozen terms).
- The SRM measure agrees well (for our limited data set) with observed
beer luminance in which sense looking at beer with SRM is like looking
at it with a black and white TV
- This is OK for most purposes since beers are all about the same hue
(if not the same saturation).
- The SRM method, like the tristimulus method is based on measurements
and thus removes the potential for errors in judgement due to fatigue,
accomodation, light quality etc. from the equation. There are still lots
of ways to stuff it up, though.
- Going along with George's comment about SRM being the first term in a
series, I'll suggest that x and y are the second and third terms and
that the series can be truncated at this point.
Final Observation - I just sat the BJCP exam. I'd never do that again if
I had to remember that Pils is about (0.66,0.354,0.372) instead of just
good old 5 SRM!
------------------------------
Date: Mon, 29 Jun 1998 05:15:13 -0700
From: Kyle Druey <druey@ibm.net>
Subject: Dry Beer
Al K describes his conundrum:
>Three words: "alcohol is sweet." Yes, I've been trying to make a
>dry IPA and I'm beginning to realise that the beer I've envisioned
>may be an impossibility at the original gravity I'm trying to use.
One possibility to dry out the beer is to increase the ion content of
sulphate to maybe 200-300 ppm by adding some calcium sulphate to the
boil (maybe 2 tsp per 5 gallons?).
Sam Mize never drove the HBD welcome wagon to my in*box, what's the
deal?
Kyle
Bakersfield, CA
------------------------------
Date: Mon, 29 Jun 1998 05:31:27 -0700
From: Kyle Druey <druey@ibm.net>
Subject: RIMS Does Not Require a Thin Mash
Al K on RIMS and a thin mash:
>you will need to have a *very* thin mash.
Not as thin as you might think. The dead space in my RIMS tun is 0.75
gal, then I need another 0.25 gal of water that fills the RIMS piping.
For 5 gal of a 50 gravity beer I need about 9 pounds of malt. I use a
water to grist ratio of 0.9 qts/lb:
total mash water = [(0.75 + 0.25)*4 + (9*0.9)] / 9 = 1.34 qts/lb
I am no xpurt, but I don't think 1.34 qts/lb qualifies as a thin mash.
>Remember that in addition to the liquid that you normally have in
>the grain bed, you also have to have enough *additional* liquid to
>fill your heat exchanger.
Yes, see above. For my RIMS tun and piping this additional water is
only 1 gallon.
>Too thin a mash means your enzymes are very dilute, which in turn,
>means that conversion will go slower and your enzymes will be more
>easily denatured (this is just a fact of thin mashes).
If you are mashing without circulating I think this is valid. But for
RIMS, I don't think this applies. The enzymes are exposed much much of
the grain surface area than with kettle mashing due to the constant
circulation (some call this "recirculation"). Conversion is very rapid,
less than 30 minutes in most cases.
Kyle
Bakersfield, CA
------------------------------
Date: Sun, 28 Jun 1998 19:39:29 -0700
From: "Michael Kowalczyk" <mikekowal@megsinet.net>
Subject: End of my career as a brewer?
I'm thinkin Paul Niebergall is a pretty "Aware" guy. I'm tired too of the
people pooh poohing techniques. I risk my career as a brewer by posting,
because of this passion we all share and the amount of influence this forum
brings...but come on!
Al writes...
Bill writes:
>I use a glass on steel 5-gallon pot as mash tun for most of the beers I
>brew. <snip>
and:
>Transferring the mash to the lauter tun only takes a couple of minutes and
>allows the filter bed to set up better the in the single tun method. <snip>
How so? I mash and laeuter in a single 18.75-gallon SS kettle into which is
mounted three EasyMasher(tm)-like screens that are connected with a SS
cross which is connected to a ball valve on the outside. I have never had
any trouble establishing a filter bed (although I have not tried rye or
wheat in this tun) and it has held as much as 46 pounds of malt. It has a
50,000 BTU ring burner under it. See my website for photos.
Also, wouldn't the transfer of the mash from mashtun to laeutertun increase
the amount of aeration of the mash that goes on? I have always
tried to be very careful to minimise introduction of air during the mash, but
I believe that Charlie Scandrett once posted that the introduction
of air in the mash may be more detremental than post boil hot-side aeration.
Isn't simpler better?
____
End of post.
I've re-read this post 6 times, so I don't think I'm jumping the gun here.
Al, Don't discount a technique simply because you don't beleive in it, or
have not tried it. I've made 38 beers using a canning kettle as a mash tun
and a phils phloating bottom. It requires me to mash and lauter in different
vessels. I transfer the mash very carefully and it only takes me a few
minutes (as Bill writes) to transfer. I usually mash-out a little higher
because I know the transfer looses heat.
Of the 38 beers I've made, I've had 3 of them after a year and more with what
I would call (of course I'm not trained at Seibel) no bad taste. Nothing that
I would call aeration of the mash. Of these beers I've never dumped one.
Not even the one you helped me with (thanks Al..).
I've stopped entering competitions after my 3rd batch (that one got me a
"Very Good" on the score sheet). My technique changes constantly. I only
brew to please me and my beer snob friends. The only real measurable
feedback I have is that I can never keep a good cellar going because my
friends alaways raid it.. I can live with that as a measure of how good my
beer is.
Please don't discount techniques. People have been brewing since the pyramids
were built. I'm sure there are more than one or two techniques that have
made outstanding beer in the years....
- Mike Kowalczyk
Dirty Spammer Brewery
Wrigleyville, Ill.
p.s. After a 7th time re-reading this, it looks like Al took exception to
"allows the filter bed to set up better the in the single tun method" of
which I respond. " I kind of agree with Al that the single tun method would
set up a pretty good bed in it's own right."
------------------------------
Date: Sun, 28 Jun 1998 22:55:27 -0700
From: John_E_Schnupp@amat.com
Subject: re: Citric beer
>Has anyone ever tried to use lemon or other citrus fruit in the secondary
>(particularly in wheat beer)? What was the result and how much did you
add?
Yeah, I tried. I used the zest and juice of two lemons in a recent 5
gallon
batch of a blonde ale. It wasn't a wheat beer but it is a light colored
and
flavored beer. It was a beer which I have brewed many times in the past
years. It's a great tasting summer swill beer. It was an extract brew.
The lemon is very obvious both to the nose and the mouth. This beer is now
about 2 months old and the lemon smell and flavor is becoming more smooth.
I then brewed my first all grain batch of the same recipe. I did all the
grain and hop calculations. I wanted to be able to compare the difference
between the mash and extract versions. I did make one change in the
extract
version. I added the zest and juice of only 1 lemon to the secondary. I
have not bottled it yet and won't get to do it until the end of July as
previous commitments will keep me away from home.
I got the zest by using a vegetable peeler. Just make sure you don't get
the white pith just under the skin. I then cut the peeled lemons in half
and squeezed them to get the juice.
John Schnupp, N3CNL
Colchester, VT
95 XLH 1200
------------------------------
End of HOMEBREW Digest #2754, 06/30/98
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