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HOMEBREW Digest #2611
HOMEBREW Digest #2611 Fri 16 January 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:
Why Pellets have Higher Utilization than Whole Hops (Charles Burns)
John Bull Wheat Syrup (Wayne_Kozun)
Ceramic heaters and extremely cold temps. (Ralph Link)
Rob & George (michael rose)
Thermometers (Al Korzonas)
Keeping Warm (Ari Shapiro)
Reminder: National Bay Area Brew Off ("Bryan L. Gros")
registering a homebrew club with AHA ("Kevin TenBrink")
World Cup of Beer (Dave Sapsis)
Re: Blade Shearing and Other Strange Fluid Mechanics (Jim Bentson)
Costa Rican Beer, Pura Vida (Mark Tumarkin)
more on labels (Mark Tumarkin)
RE: Will any CO2 do? (Margie and Dave Ludwig)
Various stuff (George De Piro)
diacetyl (Andy Walsh)
mixmasher, steam, etc ("David Hill")
Infusion vrs. Step Infusions ("Olin J. Schultz")
Tagline - Changing the Past (Overstreet)
To decoct or not to decoct? (SBireley)
RIMS mashing problems with lager malt (SBireley)
alcoholism <?> ("Michael Gerholdt")
Zima ("Gabi Scharfetter")
RIMS aka Rodney Morris ("Mark Ellis")
Irish moss (Adam Holmes)
Sparge Quittin' Time / 30 minutes of Oxygen (KennyEddy)
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JANITORS on duty: Pat Babcock and Karl Lutzen (janitor@hbd.org)
----------------------------------------------------------------------
Date: Mon, 12 Jan 98 07:47 PST
From: cburns@egusd.k12.ca.us (Charles Burns)
Subject: Why Pellets have Higher Utilization than Whole Hops
Lizardhead (Mark Youngquist?) states in HBD#2606:
"Lower temperatures may make whole hop flowers (water content
approx 8%) shatter more easily, but the lower water content of pellets
make them far less susceptable to any freezing damage."
So, an ounce of pellets is not equal to an ounce of cones due to moisture
content? I always thought we got higher utilization due to the busted up
lupulin glands on pellet hops. Can we get confirmation from a hop processor
on this?
Charley in N.cal
- ---------------------------------------------------------------
Charles Burns, Director, Information Systems
Elk Grove Unified School District
cburns@egusd.k12.ca.us, http://www.egusd.k12.ca.us
916-686-7710 (voice), 916-686-4451 (fax)
------------------------------
Date: Mon, 12 Jan 1998 11:33:45 -0500
From: Wayne_Kozun@otpp.com
Subject: John Bull Wheat Syrup
I am going to start a batch of an extract p-Lambic and I have obtained a
1.5kg can of unhopped John Bull Wheat Syrup. Under ingredients it lists
Malt Extract, Wheat Extract, but it doesn't mention what proportion is
wheat and what proportion is barley malt. Since malt is listed before
wheat I would assume it is less than 50% wheat. Would anyone know what the
proportions are, or know how I can find out. It doesn't appear as if the
John Bull company has a web site.
------------------------------
Date: Mon, 12 Jan 1998 11:17:25 -0600
From: Ralph Link <rlink@minet.gov.mb.ca>
Subject: Ceramic heaters and extremely cold temps.
I live in Winnipeg Manitoba Canada, the outside temp. this morning was -30
C.For those of you who relate to Fahrenheit this is -22 F. Yesterday with
the help of several friends we brewed our 5th batch. We currently have 46
liters of Lager in an incubator, which we have taken out and left sitting
on some fibre class bats in our garage area. The incubator is a large old
wooden tool box aprox. 2 ft. wide 5 feet long and 2.5 ft. high. I have
insulated it with scrapes of Styrofoam board and installed a small ceramic
heater connected to a Honeywell thermostat. I have placed a piece of
stainless steel plate in the box aprox. a foot square and face the heater
into the plate so as to reflect the heat and not cause a hot spot on any of
the carboys, be it a primary of secondary.
I doubt that there are many people out there who live in as harsh a climate
as we do and yet this little ceramic heater does the job.
I have been reading several notice re using lights and I believe these
ceramic heater are a better option, safety, no light are the major reasons
also the controllability.
I offer this posting as advise only and if I can help anyone with further
information please feel free to contact us via e-mail.
Ralph Link
"Some people dream of success------while others wake up and work at it.
------------------------------
Date: Mon, 12 Jan 1998 10:57:13 -0800
From: michael rose <mrose@ucr.campus.mci.net>
Subject: Rob & George
Rob & George
1 What textbooks are you using?
2 Are they avaiable to the public?
3 Do you recommend them?
thanks, mike rose riverside,ca mrose@ucr.campus.mci.net
------------------------------
Date: Mon, 12 Jan 1998 13:22:57 -0600 (CST)
From: Al Korzonas <korz@xnet.com>
Subject: Thermometers
Jim writes:
>Don't do it.. A fixed thermometer in a mash tun is most like to give you
>some very deceptive information.. I find it essential to have a long stemed
>thermometer to move around while changing to a new temp rest. When I get
>similar readings all over I know the mash temp is stable. A single data
>point wont do it. be real careful here!!!
My mashtun has a thermometer mounted in the side (see my website for photos).
When I made my first batch with the new setup, I was alarmed that my
thermometer (when compared to the trusty (although not necessarily accurate)
floating thermometer) seemed to be very slow to respond. It's a bimetal
in a huge stainless thermowell. I complained to my Dad about this and
surprise... a new digital thermometer from Omega with a 24" probe for
X-mas (1996).
On the next batch, I poked around in the mash with the new Omega and
found that while the bimetal was reading 155F, the Omega read anywhere
from 145F to 165F, depending on where you poked it. No amount of stirring
with my 3-foot restaurant-grade wooden spoon made any difference. So you
know what I did?
Nothing... that's right... nothing. My beer came out great before I
knew that my temperatures were all over the place and it still comes
out great a year after I found out that my temperatures were all over
the place. I could build myself a mixmasher or a RIMS, but I'm happy
with my beer and when I mash at what the bimetal says is 149F the
beer comes out more fermentable and when I mash at what the bimetal
says is 159F it comes out less fermentable, so why worry?
Enzymes are all statistics and half-lives... and I never did that well at
those topics in college, so I choose to ignore the science and treat
this aspect of the mash as a "black box"... I merely control the
inputs as best I can and as long as the outputs come out predictable
(and tasty), I'm happy.
Al.
Al Korzonas, Palos Hills, IL
korz@xnet.com
My new website (still under construction, but up-and-running):
http://www.brewinfo.com/brewinfo/
------------------------------
Date: Mon, 12 Jan 1998 13:01:33 -0800 (PST)
From: Ari Shapiro <arishapiro@yahoo.com>
Subject: Keeping Warm
Greetings all!
First a thanks to all of you for a great tool. I Lurk the HBD daily,
however this is my first post.
In regards to keeping warm, I have found that an old submersible
aquarium heater placed in a keg bucket full of water keeps a nice
constant bath temp for my carboys to soak in. Place a towel or
blanket over the top of the carboy and bucket to keep the heat in and
the light out. Set the built-in heater thermostat to keep the temp
you want and ferment happily away.
I guess this is the reverse of using the keg bucket full of water with
a carboy wrapped in a towel to wick the water and cool by evaporation
method.
By the way, thanks to the HBD for that Idea, that's what gave me the
idea for the way to keep warm.
~A
_________________________________________________________
DO YOU YAHOO!?
Get your free @yahoo.com address at http://mail.yahoo.com
------------------------------
Date: Mon, 12 Jan 1998 14:04:05 -0800
From: "Bryan L. Gros" <gros@bigfoot.com>
Subject: Reminder: National Bay Area Brew Off
We've begun accepting entries for the 12th annual
National Bay Area Brew Off.
Entries accepted Jan 10 to Jan 24.
Judging Feb.7 in the HopYard in Pleasanton, CA.
$6 per entry.
We're awarding prizes in the following eight categories:
American Pale Ales (Am. Pale Ale, Am. Amber Ale)
English Pale Ales (Bitters, IPA)
Dark Lagers (Fest/Marzen, Bock, Dunkel, Schwartz)
Stout
Porter
Holiday (fruit and spiced beers)
Barleywine/WheatWine.
Mead
With your entry, please specify which style (e.g. dry stout)
your beer is, what kind of mead you have, or what special
ingredients you've used.
One entry per category per brewer.
See the web page for complete details:
http://www.dnai.com/~thor/dboard/babo98.htm
or email me at gros@bigfoot.com.
Potential stewards and judges should also contact me.
- Bryan Gros
Competition Organizer.
Visit the Draught Board Web Site:
http://www.dnai.com/~thor/dboard/
------------------------------
Date: Mon, 12 Jan 1998 16:07:50 PST
From: "Kevin TenBrink" <nine_inch_ales@hotmail.com>
Subject: registering a homebrew club with AHA
Does anyone know the process by which one registers their club with the
AHA? The reason I ask here, is because my requests for information from
the AHA seem to have fallen on deaf ears. I have mailed twice
requesting information and have yet to receive a response.
If anyone can help with this, please respond via e-mail, no need
clogging the digest.
thanks in advance for your help
kevin in Salt Lake City
nine_inch_ales@hotmail.com
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
------------------------------
Date: Mon, 12 Jan 1998 16:34:34 -0800
From: Dave Sapsis <DAVE_SAPSIS@fire.ca.gov>
Subject: World Cup of Beer
ANNOUNCING the FOURTH ANNUAL WORLD CUP OF BEER HOMEBREW COMPETITION
Homebrewers and Judges,
In the spirit of recognizing the development of endemic styles
of beer, the Bay Area Mashers are proud to present the 4nd annual
World Cup of Beer Homebrew Competition. We invite you to enter and
judge this event.
The competition is sanctioned by the BJCP and is a left coast qualifying
event for
the MCAB national competition.
The deadline for receiving entries is March 14, 1998; The judge
registration deadline is also March 14, 1998. Final judging will
be conducted on March 28, in Berkeley. Like last year, we'll work to
ensure a nice resturant environment, with proper beer serving
temperatures, and clean glassware to ease your job. Ribbons and prizes
will be awarded to 1st, 2nd, and 3rd place finishers in each category,
and to Best of Show. Winners in MCAB related categories will become
eligable for entry to the national competition.
After judging, we invite you to a party at Golden Pacific Brewing to
relax, interact with the professional and amateur brewers who are
reviving quality brewing in the Bay Area. The afternoon will then
culimate with an awards ceremony.
For more information please check out out Web page at:
http://www.slip.net/~tcedit/worldcup.htm
For more judging information please contact our judge coordinator, David
Klein, at:
klein@wenet.net
For a snailmail entrant package,or other archaic information, send a
note to the comp organizer, Doug Ashcraft:
ashcraftmd@aol.com
Me? I'm just the head doofus.
- --dave sapsis, pioneering new ways to make dunkelrauchens, in
Sacramento, CA.
------------------------------
Date: Mon, 12 Jan 1998 20:29:52 -0500
From: Jim Bentson <jbentson@htp.net>
Subject: Re: Blade Shearing and Other Strange Fluid Mechanics
Recently Kyle Druey posted some comments and qoutes that contained some
technical comments regarding fluid mechanics and heat transfer.
Unfortunately there were some misstatements of technical fact. This post is
to correct those errors. It is NOT an attempt to comment on the effect of
shear forces on beer or enzymes
>In Charlie Scandrett's informative post from yesterday he brings up some
>design challenges associated with mash mixing and possibly RIMS:
>>The heat transfer problem is the formation of boundary layers and the
>>overheating of them.
The boundary layer is a thin layer which forms between the blade and the
fluid. I don't think that heat transfer in the boundary layer plays any part
here as this would be TO or FROM the blade which would quickly reach the
local temperature of the mash. The purpose of mixing the mash is to
mechanically remove temperature differences by stirring. During mixing of a
mash, the heat is transferred largely by conduction through the contact
points of the grain and the 'mechanical" convection of the surrounding fluid
due to the stirring action. Depending on the speed and geometry of the
mixing blade, the mixing action may come about by vortex shedding of the
blade or simple mechanical displacement of the grain. The former case will
cause shear stresses which are related to velocity gradients ( local
changes) in the fluid
The speed necessary for turbulent flow to prevent
>>these boundary layers is greater than the optimum for low oxidation and
>>shear degradation.
Turbulent flow is, in the context used here, one of two forms of boundary
layer flow ( laminar being the other). It is a TYPE of boundary layer. It
does not PREVENT a boundary layer. In fact turbulent boundary layers are
actually thicker than laminar boundary layers
>
>If the mixing is slowed enough to avoid a vortex and shearing, then
>perhaps now the flow is laminar producing boundary layers and uneven
>heating (the thermodynamicists out there please correct me if I am
>wrong).
Laminar boundary layers do not produce 'uneven' heating. They are just less
efficient than a turbulent layer in moving heat to or from a solid wall, ie
the heat transfer coefficient is lower in laminar flow. If the vortex is
weak enough so that poor mixing occurs, then the whole purpose for the
blades is being defeated.
I believe that the main point is that IF the geometry of the mixer should be
such that you get mixing without creating large shear stresses.(George Fix :
correct this if I am misreading the quote from your book). To acheive this,
a high angle of attack blade with minimal separation on the upper surface
would be desired. Usually cambered blades with a nose to tail angle of about
10 degs will be best for this pupose. When rotated, they cause a vertical
displacement of the mash relative to the blade plane of rotation and induce
the 'mixing' of the mash the same as a fan 'pulls' air through it due to the
aerodynamic action of the blades.
>This may relate to mash mixing, but does it relate to RIMS? Does the
>liquid part of the mash that is recirculated create the same shearing
>problems as with mixing?
No. With no blade moving, there is no mechanical surface to create
significant shear layers or vortices in the flow. If this were a problem,
then rapid sparging would cause the same problem. There is a small
boundary layer that forms on EACH particle of grain as the wort flows
through the bed but the flow velocities are so low that aerodynamicists call
this 'creeping' flow. The velocity over a blade is much higher.
Jim Bentson
Centerport (Long Island) NY
- --
Registered ICC User
check out http://www.usefulware.com/~jfoltz
------------------------------
Date: Mon, 12 Jan 1998 21:11:08 -0500
From: Mark Tumarkin <tumarkin@mindspring.com>
Subject: Costa Rican Beer, Pura Vida
I just got back from a two-week trip to Costa Rica (way south of Jeff) and
want to give you a beer report. It's a great country but I gotta tell you,
in plain language - the beer sucks. Basically, all they have is insipid,
tasteless lagers (kinda like budmilloors, only worse). Here they are in
order of preference (a relative term!).
The best of the batch was Tropical, it had a little hops flavor and
somewhat more character than the rest. Steinbrau was the only dark beer -
sort of a vienna type, some malty flavor but not much. Imperial seems to
the most popular but it was pretty bland. Pilsen is insipid and Bavarian is
even more tasteless. The only one I found but didn't try was Rock Ice -
but somehow I doubt I missed much. Suffice it to say that when we were at
the fishing lodge, I pretty much stuck to gin and tonics! I really enjoyed
the trip but it sure was nice to get home and drink some homebrew and some
SN Celebration ale.
I did pick up something I really like - a new name for my brewery. Pura
Vida HomeBrewery. Pura Vida is Costa Rican slang. It literally means Pure
Life, but it's sort of a multi-purpose phrase, kind of like aloha. It is
used for hello, for good bye, for what's up, for this is as good as it
gets, and other similar uses. I love it. Pura Vida, HBDers!
Mark Tumarkin
Pura Vida HomeBrewery
Gainesville, FL
------------------------------
Date: Mon, 12 Jan 1998 22:24:46 -0500
From: Mark Tumarkin <tumarkin@mindspring.com>
Subject: more on labels
Just beginning to get caught up on my email after getting back from Costa
Rica, and of course the first things I'm reading are the HBDs. Amazing how
much I missed it, am I addicted? Speaking of addictions, it seems that the
only thing worse than an alcoholic homebrewer is an alcoholic homebrewer
with botulism who's wife won't let him brew in her kitchen. Sorry about
that...
A couple of things on the label thread, milk does make an effective (and
cheap and easy) glue but it tends to come off if you put the bottles in an
ice chest at a party. I have tried a number of adhesives and the one that
I am most satisfied with is the UHU glue stick. It stays on very well, but
comes off easily in a light ammonia soak. Recently I have been using the
purple ones. They work exactly the same as the plain white but the color
makes it much easier to see where you have already applied the glue and
thus to get complete coverage without going over areas twice.
Also with the ice chest hazard in mind, my wife came up with a good
suggestion. At her prompting, I started covering the labels with clear
contact paper before cutting them out. Actually, I cut the pages of labels
into strips and then apply the contact paper so that I don't waste very
much. This protective covering assures that the colors from the inkjet
printer won't run, and also helps keep the labels coming off prematurely.
It took a little practice to get the technique for applying the contact
paper smoothly so that you don't get air bubbles. You can push some bubbles
to the edges with your thumb or a hard plastic tool, but try to keep them
to a minimum as you put on the contact paper.
As far as software, I simply download images from the Net, save them as bmp
files and then you can add text using any paint program (including the
accessory built into Windows). Easy and you don't need any other software.
I used a satellite image of Hurricane Andrew (directly over my house) that
I found on a NOAH site for my Cat 5 Pale Ale - a tremendously hopped Andrew
anniversary ale. Really looked great!
Labels are an added hassle and expense (especially when using the contact
paper) but you sure get a good response to your bottles. I guess I feel
presentation is just another part of the brewing art. If you enjoy it, then
do it. If not, a marker or tape works just fine. Or another thing that
works well to distinguish batches is to use those small colored dot labels
often used as price stickers. They are cheap and come in many different
colors. I enjoy doing the labels but YMMV, whatever works for you.
Mark Tumarkin
Pura Vida HomeBrewery
Gainesville, FL
------------------------------
Date: Mon, 12 Jan 1998 22:44:48 -0500
From: Margie and Dave Ludwig <dludwig@eagle1.eaglenet.com>
Subject: RE: Will any CO2 do?
Ed Choromanski asked:
>needing to get my CO2 tank filled. I was wondering if there is
>anything special about the CO2 needed. The reason why, is I have
>gotten a price of $13 from the welding supply shop that is very
>convenient and that is about $6-$16 cheaper than some other
>non-welding places I have called. I just want to be sure, it's my
>first time and I don't want anyone getting sick or worse. Or is CO2
>just CO2 and I am being anal?
>
>Also, I saw that the welding supply shop had a pressure requlator (has
>both tank and output pressure dials). What pressure range for both
>the tank and output should I purchase? The one they had was $75 with
>output range of 100 psi and tank range of 4000 psi (seems a bit much).
>
Ed,
I bought my 5lb bottle, valve, regulator and guages from a local welding
supplier. I haven't noticed any quality problems with the CO2, but YMMV.
Frankly I've wondered the same thing. Just how clean is this CO2 that we
buy? I'm not worrying about it, though. The regulator I bought had an
ARGON/CO2 CFM guage on it which is essentially a pressure gage calibrated
to read CFM with the installed orifice (at low back pressure). My welding
store swapped that unit for a 0-30 psi gage, which works nicely for me. I
would trade the 100 psi gage for a 30 psi gage. That way you get a more
useful gage range especially when you set low pressure for dispensing.
(Haven't done in a year or so but like 3-5 psi.) The 4000 psi gage is
alright for this purpose.
Dave Ludwig
Southern MD Brew
------------------------------
Date: Tue, 13 Jan 1998 00:17:59 -0800
From: George De Piro <gdepiro@fcc.net>
Subject: Various stuff
Hi all,
I=92ll address a couple of things that have caught my eye recently:
Hubert talks about the importance of providing the yeast with oxygen =
during propagation. He is quite correct to emphasize this. The amount =
of oxygen available to the yeast limits how many times they can =
reproduce. Oxygen is used by yeast to produce oleic acid and sterols =
(both are important to membrane integrity). The most sterol a yeast cell =
can contain is about 1% by weight. A yeast cell must contain > 0.1% =
sterol in order to remain viable.
What does this mean to you? It means that if you aerate the wort at =
pitching time, the yeast will take up all the oxygen and build up their =
sterol levels to the 1% max (if you gave them enough O2). If you provide =
no more oxygen, then that is all the sterol the cells will contain. When =
the cell buds, the daughter cell and mother cell will each have about =
0.5% sterol. Two more divisions gets each cell down to 0.125% sterol. =
Because the cell needs at least 0.1% to live, it won=92t divide anymore.
If you only provide O2 at the beginning, the yeast can only go through 3 =
divisions, giving you eight times more yeast than when you started. If =
you are trying to propagate yeast, you may have a need for more yeast =
than this. You must therefore provide more oxygen during the =
propagation to allow more cell divisions.
All the talk about Jack=92s =93Mixmasher=94 had me thinking, =93Gee, it see=
ms =
very likely that all that mixing is really going to put people at risk =
for stuck Lauters.=94 Then somebody posted that they had stuck Lauters =
when constantly mixing their mash! One thing that has been stressed here =
at Siebel is the importance of mash mixer design and operation. HSA is =
only a secondary concern; the first problem is that shear forces can =
severely damage the malt husks, making for very tough lautering. Even =
with a properly designed mixer, running it for too long will make =
lautering a nightmare (we learned about real-life examples).
I=92m not saying that the mash mixer can=92t work, but you must be careful =
and know the potential pitfalls so you can avoid them.
I=92m still having a blast here at Siebel. Class is 9 hours a day, plus =
time spent talking with the instructors and students after class. Of =
course, the topics are always brewing related, so it=92s really not too =
much of a hardship. It=92s really cool!
Speaking of cool, the Map Room on Armitage and Hoyne is really great: =
good beer selection, nice atmosphere, etc. Free food on Tuesday nights. =
I=92ll be there tomorrow and next week!
Oh yeah, my E-mail hasn=92t been going through with great regularity: the =
corn meal thing: degermed corn meal is the rule for most (if not all) =
big brewers. That cuts the oil content more than 50%. However, the =
teachers here at Siebel said that if head retention was not harmed, the =
other concern would be flavor stability. So, when I get home, I=92ll let =
you all know how my 20% whole corn meal CAP turns out...
Also, Dave wanted to know about diastatic power of raw grains. It is =
nil. Almost all the amylases are developed during the malting process. =
I=92m still looking for exact numbers, though (they are hard to find =
because all the books I have looked in talk about the fact that they need =
to be mashed with diastatic malt!).
Several people have asked us about protein rests and modern malts. The =
=93simple=94 answer is to not do them (as many of you already know). The =
more accurate answer is to check out a malt analysis. Check out the =
modification level by comparing the coarse/fine grind extract difference, =
and the soluble :total N ratio (Kolbach ratio). While the Kolbach ratio =
alone is not a perfect indicator of malt modification, when considered =
with other parameters, it is useful. A Kolbach reading of <35 is =
indicative of undermodified malt. 35-41 is well modified, while >41 is =
very highly modified (from a protein standpoint, not a cell wall break =
down view).
The coarse/fine difference is a good indicator of malt modification: the =
smaller the difference, the more modified the malt. 1.2-1.8% difference =
is typical of today=92s European malts. They=92re all pretty well modified=
, =
and you could probably get away without any protein rest. If you do have =
haze problems in a test batch, you can then add a higher-temp protein =
rest to combat it.
Have fun!
George De Piro (Chicago, IL)
------------------------------
Date: Tue, 13 Jan 1998 19:36:00 -0800
From: Andy Walsh <awalsh@crl.com.au>
Subject: diacetyl
from Samuel Mize:
>After the yeast have been working, the wort contains alcohols. These
>oxidize rapidly, creating diacetyl.
Great, I'll use this as an excuse to talk about diacetyl. Skip to the
end of the post if you are bored by technical discussion....
I think Samuel's description of the process is a little bit misleading.
The primary compounds involved in diacetyl formation are pyruvate and
alpha acetolactate.
pyruvate CH3COCOOH
OH
|
alpha acetolactate CH3COOH
|
C=O
|
CH3
O O
|| ||
diacetyl CH3-C - C -CH3
OH OH
| |
2,3-butanediol CH3-C - C -CH3
(The only major flavour active one of these is diacetyl)
Pyruvate is a very important component during glycolysis (fermentation),
and most pyruvate is used in ethanol production, but some is used in
biosynthetic reactions (ie. during log phase). Alpha acetolactate is
enzymatically formed via this pathway from pyruvate.
ie. pyruvate + enzyme -> alpha acetolactate
Only about 4% of alpha acetolactate formed in beer is oxidised to
diacetyl. Molecular oxygen is not necessary for this as other electron
donors (eg. Cu++) can also oxidise alpha acetolactate to diacetyl.
Addition of air or increasing temperature during (or after) fermentation
can increase diacetyl levels by oxidising alpha acetolactate (also by
kickstarting yeast growth again).
Yeast does nothing with alpha acetolactate but readily assimilates
diacetyl, which is further reduced to 2,3-butanediol (not flavour
active). Diacetyl rests encourage this reaction.
Why all this detail? A while ago I asked on the HBD if anyone had used
Novo Nordisk's product "Maturex", which is simply the enzyme
alpha-acetolactate decarboxylase. I received no response, so possibly
nobody had used it (either that or nobody reads my boring posts!). This
enzyme breaks alpha acetolactate down to 2,3-butanediol directly,
bypassing the diacetyl step. ie. One does not need to incorporate
diacetyl rests if Maturex is used. The manufacturer also claims you can
shorten or even eliminate the maturation phase, since diacetyl reduction
is possibly the main reason for such rests. (their claim, not mine)
If one does not want diacetyl in a lager it can be quite frustrating at
times. Some yeasts produce loads of it (Wyeast Munich comes immediately
to mind), and even if you incorporate special rests and long lagering
periods it can pop up unexpectedly (eg. transferring to keg if you are a
bit sloppy).
I have scored some of this enzyme from a local microbrewery and used it
just once in a lager recently. I used Wyeast Danish II which has given
me occassional hints of diacetyl before. Well the finished beer has been
in the keg for just one week (no secondary, 2 weeks primary at 10C) and
there is certainly not a bit of diacetyl detectable. It is really very
tasty right now - I am sure it could benefit from some further age, but
the manufacturer's claims seem largely justified. My flatmate used a
sample of the same yeast without Maturex (yes we are a two brewer
household) and produced a lager that just reeks of diacetyl!
What is really obvious in the beer I made is the complete *lack* of
diacetyl. I think often it is there around threshold levels, providing a
background sweetness, but not so much as to make you be aware of it. The
brewer at the brewpub I obtained the Maturex from has found the same.
The first beers made with it were apparently very bitter - obviously the
sweetness/bitter balance was way off because of the change in process.
They have since dropped the hopping level to compensate. IMHO this is
one reason Pilsener Urquell can cope with its high bitterness, because
of high residual diacetyl levels. To my nose massive diacetyl butter
character does not exist in PU, but there is enough there to give
sweetness to counterpoint the hops.
So, Maturex is cheap and you use just 1ml per 100l of beer, so why don't
homebrewers use the stuff? My impression is that it won't "fix" a
diacetyl problem (too late!), but it appears to have no adverse affects
(it shouldn't either from the biochemistry), so I may use it as a matter
of course in future lagers, especially when using a suspect yeast
strain. It's not Reinheitsgebot by any means but as a pointy headed type
rather than a traditionalist, I really don't care! Brewers who cannot
incorporate diacetyl rests for whatever reason should also benefit.
Diacetyl lovers like our friend Dr. Pivo (apparently it takes all
types!) should stay away though.
So come on all you homebrew shop proprietors!
Andy Walsh. - Diacetyl free in Sydney.
PS. Novo Nordisk have a number of other enzyme treatments - like high
temperature (95C) alpha amylase. Buy it by the Wohlgemuth Unit!
------------------------------
Date: Tue, 13 Jan 1998 19:34:23 +1100
From: "David Hill" <davidh@melbpc.org.au>
Subject: mixmasher, steam, etc
Charlie S's suggestion to use an electric element to stir the mash =
raised the question of how to get the power to the rotating element in =
safe manner within an amateur cost constrained system.
=20
A thought:-
=20
could not ff using a round Rubbermaid, Gott or similar, the mash tun =
could be made to rotate around a fixed electrical element or steam =
injector manifold. A simple belt driven turntable would do the job.
=20
Obviously sparge run off plumbing would need to be disconnected during =
the rotation/mixing/mashing/injecting phase.
=20
practical?
=20
David Hill
=20
David Hill. davidh@melbpc.org.au :-)>
------------------------------
Date: Tue, 13 Jan 1998 00:36:52 -0800
From: "Olin J. Schultz" <beerx3@ix.netcom.com>
Subject: Infusion vrs. Step Infusions
I sent in a post a couple digests back asking for actual experiences of
those who have done infusion and step mashing with the same recipes. I
stated that I have a mixmasher made from an old ice cream maker. Well
instead of any responses about the two different mashing schedules all I
got were inquiries on how to build the mixmasher! Which is fine and I
was happy to answer but again I pose the question:
Why are you all doing step mashes in the first place? Although it has
been in the digest before I think this question should be answered again
while 'how best to step mash' is a hot topic. In my personal opinion,
both the mixmasher and rims are solutions looking for a problem to
solve.
The advantages touted for step mashing, and the reason I tried it, are
perhaps a slighlty higher efficiency(which is pretty neglible on a
homebrew scale), higher amino acid content which is unecessary with
modern malts, and better clarity. But I cant tell any clarity
difference in beers made with an infusion mashing schedule. Perhaps with
some German pils it may be necessary, but I have not seen the malt. I
heard somewhere that even some German breweries that do not decoct are
going with infusion because the modern malts have a higher degree of
modification. Clear runoff is touted as being a plus for rims but I have
just never had a problem with clear runoff using infusion and minimal
recirculation of at most a couple quarts. Now with my new system(R)
recirculation is barely necessary at all.
The disadvantages of step mashing. The biggest is less head retention.
This is more noticeable on lighter beers. On high gravity beers you get
good head as a default of the higher percentages of head stability
constituents. The other factor is that step mashing provides for more
exposure to the beta amylase set of enzymes, which results in thinner
beers. This may or may not be desired, but most homebrewers are
generally looking for good body. Good heat control. I lose maybe one
to two degrees in my stainless mashtun over an hour, uninsulated. None
if I insulate. I have a 6 inch probe thermometer.
Step mashing is also more time consuming on brew day and the equipment
needed to perform it easily are either big forearms, a mixmasher, or
rims.
I love excess in a hobby, but instead of spending time and money on step
mashing why not build the World's largest rolling non motorized portable
beer dispenser! I apologize in advance, but I have to brag about our
Tiki Hut System(R) :) We, brothers and I, have a 1000lb.(or more) 5
tap, 4 sided oak, rolling tiki hut bar, complete with thatched roof, 2
mini tv's, generator, 2 blenders, running water(via gravity from a tank
under the false roof), 100 watt denon/infinity stereo system, and water
misting system to keep us cool while drinking. Fits 4 kegs of homebrew
and 2 kegs of margaritas. We push/pull it at a slow walk every year
with over 100 friends in the 7.5 mile Bay to Breakers race in San
Francisco. That is all it is used for, except that an advertising
agency for Miller contacted us for shooting a commercial during the race
but we would have had to drink O'douls for legal reasons. Not. I will
post some pictures on the web if anybody wants to see it.
Thanks for the bandwidth!
Olin Schultz
------------------------------
Date: Tue, 13 Jan 1998 08:08:04 -0600
From: Overstreet <wa5dxp@worldnet.att.net>
Subject: Tagline - Changing the Past
Someone in today's digest had the following tagline:
- ------------------------------------------
Even God cannot change the past.
- Agathon (quoted by Aristotle, NE 6:2,1139
- -----------------------------------------
Obviously Agathon did not envision the present-day
network/newsprint/publishing empires. They change the
past every day. "1984" is alive and well. -;)
------------------------------
Date: Tue, 13 Jan 98 09:05:10 EST
From: SBireley@renex.com
Subject: To decoct or not to decoct?
After trying a two step decoction mash for the first time to brew a
Mai Bock, and looking to several sources for advice on improving the
process, the overwhelming advice was "you don't need to do decoction
anymore. Todays very modified malts do not require the process and
the addition of darker malts will provide the malt profile necessary
for the styles." The references used for recipe and process were
Noonan's New Brewing Lager Beer and Steven ?'s The BrewMaster's Bible,
both of which say that decoction brewing is desireable to get the
smooth malt profile of the German lagers. I'm not opposed to
continuing to do decoction mashes, but want some indication the time
and effort is worth it. Any Comment?
------------------------------
Date: Tue, 13 Jan 98 11:10:58 EST
From: SBireley@renex.com
Subject: RIMS mashing problems with lager malt
We have done many batches in our manual RIMS system with Briess two
row ale malt with not problems at all. Without changing anything we
tried a lager using Crisp Malting two row lager malt and some Crystal
malt. We used the same mill settings same mashing procedures. The
problem we encountered was the mash compacting to the point that the
pump would not move the wort. We are investigating a variable speed
control on the pump or placing a ball valve in line with the pump
output. Thanks in advance.
------------------------------
Date: Tue, 13 Jan 1998 11:56:18 -0500
From: "Michael Gerholdt" <gerholdt@ait.fredonia.edu>
Subject: alcoholism <?>
Hi, folks,
The alcoholism thread just won't go away, will it! And so I'll put my 2
cents worth in.
The notion that alcoholism is a disease is a contrived definition. When I
say "contrived" I mean that it is not obviously a disease by normal
standards, and has been granted the definition of disease because it shares
some of the attributes of disease - at least, apparently. So there is
something rather arbitrary about using the term disease. No one would argue
that typhoid or malaria are diseases. When it comes to alcoholism, there is
plenty of room for discussion on the subject.
For this reason, I find that the dogmatic assertion of the identification
of alcoholism as disease begs far too many points to be granted as a given.
It ranks closely to religious claims in that respect, since it presumes so
much about the nature of humans, and since to question it is often
considered nearly "blasphemous." It is undeniable that many have resumed
productive and far happier lives by demonizing alcoholism to the absolute
degree. It is also undeniable that alcohol has ravaged many lives in many
ways, and will continue to do so.
What makes it difficult and "treacherous" on the face of it to have a truly
open discussion of the subject is that to question the disease-picture of
alcoholism threatens one of the basic tenets of the cure that so many in
the United States have used to "draw the line." If that is gone, so is an
absolute truth. Yet this sort of practial experience has never been a
reliable path to truth. It is, instead, a reliable path to dogma. Multiply
anecdotal experience by several million, and you still have anecdotal
experience. Just lots of it.
Practically speaking, from the traditional friend of Bill W's perspective,
to question the disease picture is simply to play with fire. It is a dear
and "true" description of alcoholism as it has effected this person's life,
and to deal with it as such has given her or him a clear stance. "Half
measures availed us nothing," they will tell you, and it is true. We cannot
but be sympathetic to their need to hold their pragmatic, practical truth.
There's little to be gained by challenging it to one who needs it to be
true, and much to be lost.
Not all of us have the need to view alcoholism in this way, however, and we
are free from that constraint. Even some of us who have consistently abused
alcoholism in the past and would pass many standard definitions of
"alcoholic" may not ascribe to the dogma that alcoholism is a disease. Some
of those drink in a more controlled manner today, and some of them drink
not at all; still others drank themselves to death. There is anecdotal
experience to support every point of view, and so anecdotal experience
cannot be the final arbiter. At the same time, we cannot discount
experience in deference to some pure untouched theory. However, we also
cannot rely only on our own experience to the exclusion of the experience
of those around us. We trade information and knowledge. We're communal
beings.
There are other approaches. I will point out that the health professions
have a vested interest in supporting the notion that alcoholism is a
disease, as do many large corporations who instead of firing the problem
drinkers are now able to support them as they receive treatment. If it's a
disease, then health insurance will often cover a significant portion of
the treatment; it it's covered by health insurance, more folks will tend to
get help; that's good for the health professions (it's more business) and
it's good for the employers (fix this trained person rather than training a
new person). So, yeah, economics and politics do enter into it.
But there's no need to play devil's advocate to mistrust the dogma.
I don't have an answer here, just some comments on the process of arriving
at one. Two sides making exclusive claims about a subject have never moved
toward any type of consensus, on the one hand, nor has such a truth-claim
fight shed much light on what is actually the case (the "truth," if you
will), on the other.
And ad homini have never achieved a thing - even when subtly and
unintentially tendered e.g., "don't listen to an alcoholic for advice on
this subject." Hey, Dave, didja know that easily 75% of the folks who are
in the "recovery" field are themselves recovering alcoholics?
Of course, it's ok to listen to them, because they're not the alcoholics
who deny that alcoholism is a disease, they're the ones who affirm it,
right?
Naw - I don't think we're qualified to discuss this subject. Let's get back
to how to make better beer . . .
Michael Gerholdt
just far enough away from absolute truth that you can't see it from here
------------------------------
Date: Tue, 13 Jan 1998 21:19:19 +0100
From: "Gabi Scharfetter" <wombat@xpoint.at>
Subject: Zima
Hello!
Is there somebody out there who knows anything about the brewing of =
"Zima"? Its a so called "clear malt", brewed by Coors. I enjoyed =
drinking it when I was on holiday in the USA. And perhaps there is a =
possibility to brew it at home?!=20
Thank you,
Gabi
------------------------------
Date: Wed, 14 Jan 1998 07:52:29 +1100
From: "Mark Ellis" <mellis@gribbles.com.au>
Subject: RIMS aka Rodney Morris
Hi HBD'ers,
Could any of you guys point me towards an original repository for Rodney
Morris's RIMS design/building/use etc. I hear plenty about his great
introductory work but I'll be damned if I can find anything that is not in
the third person.TIA
Regards
Mark Ellis
------------------------------
Date: Tue, 13 Jan 1998 14:12:01 -0700 (MST)
From: Adam Holmes <adamholm@holly.ColoState.EDU>
Subject: Irish moss
I read in the digest about peoplee rehydrating their Irish moss prior to
adding it tto the wort. They described it as becoming a gelatinous goop
after adding 1 tsp. to 1 cup water for 15 min. They then pitched the goop
into the
wort.
My question is: I just used Irish moss for the first time yesterday. I
rehydrated 1 tsp. for 15 min. in 1 cup water but it never turned into a
gelatinous blob. Do I need longer to rehydrate? Is there something wrong
with my Irish moss?
Thanks in advance,
Adam Holmes
private email OK
------------------------------
Date: Tue, 13 Jan 1998 15:59:13 EST
From: KennyEddy <KennyEddy@aol.com>
Subject: Sparge Quittin' Time / 30 minutes of Oxygen
SBireley@renex.com asks:
Is there a preferred method for determining when to stop the runoff
during sparging? We use a lab quality PH meter to monitor mash ph,
but stop our runoff at 1.010 gravity. I'm sure we are leaving good
sugar in the tun, but we do not want to over sparge. Is there a rule
of thumb?
I remember reading this somewhere (maybe here) and have no idea if it's based
in fact, but I've tried it and it seems to be a reasonable guide. The rule
says if the runoff has any discernable sweetness, it's 1.012 or higher; if it
tastes like tea (tannic/astringent) it's 1.008 or below. If it tastes like
plain hot water, it's in the 1.008 to 1.012 range.
*****
Dave Burley wrote:
"Also, note that a properly pitched quantity of yeast will reduce the
oxygen content of the wort to zero in 30 minutes (AJ DeLAnge-?)."
I remember this comment as well (pretty sure it was AJ), and it's always
bugged me in a way. Why do we go through so much trouble oxygenating our wort
if the oxygen is consumed so quickly by the relatively small amount of yeast
pitched? And if the answer is "to build cell walls and stuff", then why not
oxygenate your starter medium, allow it to sit for 30 minutes, then pitch into
a non-oxygenated main wort? What's the difference?
*****
Ken Schwartz
El Paso, TX
KennyEddy@aol.com
http://members.aol.com/kennyeddy
------------------------------
End of HOMEBREW Digest #2611, 01/16/98
*************************************
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