Homebrew Digest Wednesday, 18 September 1996 Number 2192
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FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
Shawn Steele, Digest Janitor
Thanks to Rob Gardner for making the digest happen!
Contents:
Newbie probability? (Timothy J Kniveton)
Hose pressure drop (Things that make you go 'Hmmm...') (Kelly Jones)
old fashioned brewing ((Nigel Townsend))
RIMS (computer control) (Ian Smith)
Decoction-mashed Oktoberfest Recipe (Gontarek)
Pro's homebrewing (ThE-HoMeBrEw-RaT)
Re: Vienna and Munich Malt (Don Trotter)
What hops for Red Seal Ale?? ("Robert Marshall")
Sparge Scooping Solution (KennyEddy at aol.com)
[none] ((Bob Sutton))
WHC score sheet horror (Jeff Renner)
re: cane sugar (Greg Pickles)
Pete's Wicked Ale Clone (Bret Bartlett)
Re: Imperial gallon vs. US gallon (Spencer W Thomas)
Hop filters. (Geoff Bagley)
Copper & oxidation (Andy Walsh)
copper and oxidation - the theory (Andy Walsh)
RE: Brewers raking the sparge / Munich malt and Dunkles ((George De Piro))
Re: Pro's homebrewing (RUSt1d?)
Drill bits vs. stopper sizes (Ken Sullivan)
Homebrew Competition (Special Events)
[none] (STURM)
Re: HBD buyers co-operative (Derek Lyons)
Alcohol/flame sterilant ("David R. Burley")
Korny Keg blowout ((Charley))
slow starting fermentation (TMCASTLE at am.pnu.com)
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----------------------------------------------------------------------
From: Timothy J Kniveton <tim+ at CMU.EDU>
Date: Tue, 17 Sep 1996 19:40:12 -0400 (EDT)
Subject: Newbie probability?
What is the probability that a beginning homebrewer will turn out a
decent first batch of beer? second? third?
Is it a random variable, or more of a random question?
tim
- ------------------------------
Return to table of contents
From: Kelly Jones <kejones at ptdcs2.intel.com>
Date: Tue, 17 Sep 1996 16:51:06 -0700
Subject: Hose pressure drop (Things that make you go 'Hmmm...')
I read here that 3/16" ID hose has a pressure drop of about 3 psi per foot.
So, if I use 10 feet of hose, I should get about 30 psi drop, right? Now,
if I hook this up to my keg, which is carbonated/pressurized at only 10 psi,
I should have (10 - 30) = negative 20 psi at the tap. Will this negative
presssure cause my keg to suck air back through the line into the keg, or
will the negative pressure cause the hose to collapse, thus preventing any
flow at all?
Kelly
Return to table of contents
From: nigelt at delm.tas.gov.au (Nigel Townsend)
Date: Wed, 18 Sep 1996 09:53:28 +1000
Subject: old fashioned brewing
I have come across an oldish (1883) comendium of everything from treating
consumption to making Japan ink. Amongst all this is come advice for
brewers of the day.This is a titbit for today, some ale recipies will
follow as time permits.
"Ale, Mulled
Place a pint of good ale or beer in a saucepan, with a little grated
nutmeg. When it boils take it off the fire, then sweeten. Beat two or
three eggs, and mix with a little cold also. Boil, and then add the egg to
the hot ale, pouring backwards and forwards from one vessel to the other to
prevent curdling. Rum or brandy may be added ad libitum.
Ale or Porter, to ripen
Bottle and put a couple of raisins, or a few grains of rice or sugar into
each bottle to generate the required effervescence."
cheers for now
Nigel Townsend, Hobart, Tasmania.
Return to table of contents
From: Ian Smith <rela!isrs at netcom.com>
Date: Tue, 17 Sep 1996 17:41:40 -0600 (MDT)
Subject: RIMS (computer control)
I would like to automate my mash and sparge with a computer. Is it
possible to buy a card that will convert a thermocouple (or other temp
sensor) to an input that can be read by a computer ? I would also like to
turn an electric heater on and off as well as some valves and a pump. Has
anyone tried this ?
My goal would be to be able to set the mash temp, turn on the RIMS pump
and have a computer monitor the mash temp adjusting it by switching a
heater on and off. After a predetermined amount of time (1.5 hours) I
would turn the heater on until mashout temp of 170 F and mashout for 10
minutes. Turn off the heater and RIMS pump, open a valve and sparge for
1.5 hours.
Cheers
Ian Smith
Return to table of contents
From: Gontarek <gontarek at voicenet.com>
Date: Tue, 17 Sep 1996 07:15:14 -0500
Subject: Decoction-mashed Oktoberfest Recipe
Hi Everyone,
I would like to move onto the next higher plane of all-grain
brewing...the dreaded decoction mash! I want to brew a nice
Oktoberfest/Maerzen-style beer using a (simple) two-step decoction mash
technique. I have read the Decoction Mashing Faq at the Brewery, but I
would like to get someone's tried and true recipe (and maybe some
helpful hints). Also, a while back I read what I thought was a decent
article on decoction mashing in Brew Your Own magazine, but I can't find
that particular issue. If my memory serves me correctly, the article had
a recipe for an Oktoberfest. If someone has that article and can either
give me the recipe or (if it's not asking too much) perhaps fax me a
copy, that would be wonderful.
I am aware that decoction mashing is essential for obtaining that malty,
caramelized flavor and deep garnet amber color, and I am psyched to
devote an entire Sunday to creating this brew. If anyone out there has a
great recipe based on standard mashing teachniques (not decoction), I'd
appreciate that, too (just in case I whimp out!).
Thanks a bunch,
Rick Gontarek
Owner/Brewmaster of The Major Groove Picobrewery
Trappe, PA
gontarek at voicenet.com
Return to table of contents
From: ThE-HoMeBrEw-RaT <skotrat at wwa.com>
Date: Tue, 17 Sep 1996 20:31:37 -0500
Subject: Pro's homebrewing
>From: George_De_Piro at berlex.com (George De Piro)
>Date: Tue, 17 Sep 1996 13:43:36 -0700
>Subject: RE: Pro's homebrewing
> But should people using "Brew on premises" be allowed to enter
> homebrew comps?
>
> Have Fun!
>
> George De Piro
Howdy,
This statement brings up a good point... I also expect to get alot of flames
from brewers that use BOP's, but what the who...
Questions:
1. Are brewers that use BOP's really brewing their own beer or are the BOP's
really doing most of the work for the brewers who I would assume are mostly
but not completely made up of "Fad-Brewers" and novice experimenters?
2. In My opinion this BOP process is anything but homebrewing... How does
everyone else feel about this?
3. Should a beer that is brewed at a BOP be able to be entered in an AHA or
any other Homebrew Competition? (BOP's have walk in temp controlled lagering
facilities... not the lagering fridge that I have)
4. If I go down the street and talk Weinkeller (please no jokes about the
Pub) into letting me brew a batch of beer in their testing brewery and then
lager it in their walk-in fridge all for $75 and they even bottle it I
wouldn't be able to enter it in an AHA competition so why should I or anyone
else for that matter be allowed to enter a BOP brewed beer in a competition?
They are both about the same!
5. This causes some major double standards as far as I can see so shouldn't
it be debated with the AHA and amongst Brew-Clubs?
I figure from George's initial statement there is alot that could be done
with this thread so let's take it on for a while if anyone is game (or gamey
for that matter).
**** DISCLAIMER: I AM NOT AGAINST PEOPLE THAT BREW AT BOP'S, NOR AM I SAYING
THAT YOU CAN NOT BREW GOOD BEER THERE... BUT IS IT HOMEBREWING? *****
- -Scott
################################################################
# ThE-HoMe-BrEw-RaT #
# Scott Abene <skotrat at wwa.com> #
# http://miso.wwa.com/~skotrat (the Homebrew "Beer Slut" page) #
# OR #
# http://miso.wwa.com/~skotrat/Brew-Rat-Chat/ (Brew-Rat-Chat) #
# "Get off your dead ass and brew" #
# "If beer is liquid bread, maybe bread is solid beer" #
################################################################
Return to table of contents
From: Don Trotter <dtrotter at imtn.tpd.dsccc.com>
Date: Tue, 17 Sep 1996 20:50:21 -0500
Subject: Re: Vienna and Munich Malt
Bill Griffin contradicts my earlier post on Vienna and
Munich malts. Bill is somewhat correct, however, I will
not concede 100%.
I must qualify my claim that it is possible to make beer
that will be out-of-style when using 100% Vienna or Munich
grain. First of all, I was repeating from memory of an
article I had read in the 1995 Special Issue of Zymurgy. I
agree that this should not be the only publication on malt
that I or any others should rely on, however, the article
mentioned, "Malt: A Spectrum of Colors and Flavors,"
written by Neil C. Gudmestad and Raymond J. Taylor has
quite a comprehensive list for the novice homebrewer, such
as myself. Second, I have referred back to the article to
be sure that my memory is not to blame for 100% of my
previous post. I don't wish to point fingers, but do wish
to point out facts. I'm sure other publications may
contradict these findings, but is that not splitting hairs?
Okay I was incorrect about Vienna malt.
Only two varieties of Vienna malt are listed in the
article, US and German and are only 3-4 L. When used
as 100% of the total grain bill will result in the proper
color.
I still wonder about the resulting extraction when using
German Vienna, because the malt is listed as only having
"moderate" diastatic power. US Vienna, on the other hand,
is rated as "very high" in diastatic power, but is this
not the dreaded 6-row variety?
Okay, I was partially incorrect with my assertion that using
100% Munich malt would result in a beer that is out-of-style.
There are several varieties of Munich malt listed and range in
color from 7.8 L to 30 L. Using 100% Munich to produce a Munich
Dunkel with 10 L Munich malt will result in a beer that is 22.5
SRM, which is over the range of 17-20 SRM, according to the
1995 AHA style guidelines.
Of the Munich malts listed, only two were below 10 L, and 4
were 10 L or above. Thus, it is both possible to meet the AHA
style guidelines, when brewing a 100% Munich Dunkel, and not.
I wonder also about the diastatic power of Munich. All varieties
listed are "moderate" in diastatic power. I would have to see
the actual malt analysis to predict the extraction rate, but I
have realized low extraction with malts rated higher in this
article, therefore I am pessimistic, and would prefer to use a
mixture of malts for balance - better safe than sorry.
Cough, hack, gag, gargle, phtoohey!
You may think I am half full of shit, but I ask, am I not half empty?
don
Return to table of contents
From: "Robert Marshall" <robertjm at hooked.net>
Date: Mon, 16 Sep 1996 19:35:07 +0000
Subject: What hops for Red Seal Ale??
I've been trying to do a clone of the North Coast Red Seal Ale. I had
one brewer, not affiliated in anyway with North Coast, tell me that
its 100% Centennial hops.
This weekend, I did a 5 gal. batch, with about 34 IBU and 1.050 OG. At
first taste it doesn't seem to match. (This was with an Alexander's
Pale Liquid Malt Extract base for neutralness in malt).
Can anyone suggest if I'm heading down the right path, hopwise??
Later,
Robert Marshall
robertjm at hooked.net
homepage: http://www.hooked.net/users/robertjm
- ----------------------------------------------
"In Belgium, the magistrate has the dignity
of a prince, but by Bacchus, it is true
that the brewer is king."
Emile Verhaeren (1855-1916)
Flemish writer
- ------------------------------------------------
Return to table of contents
From: KennyEddy at aol.com
Date: Tue, 17 Sep 1996 22:43:36 -0400
Subject: Sparge Scooping Solution
James Murphy asks,
"What's the best way to sparge? Right now, I use a measuring cup, scoop
about a cup of water, and slowly pour this over the grains."
Run two dowels parallel to each other through a plastic "Tupperware" style
bowl (the flatter & wider the better) that has also been drilled with a few
1/8" holes circling around the bottom. I used a one-quart bowl but you might
find one a bit bigger or smaller as you require; aim for about 1" or so
clearance above the grain bed & water. The dowels will straddle your mash
tun rim and suspend the bowl over the mash. Now just dump sparge water into
the bowl only often enough to keep the bed floating. Doesn't *eliminate*
scooping but certainly reduces the number of scoops (by about a factor of
four in your case)! By experimenting with the number of holes in the bowl,
you can actually "design-in" the sparge rate (water input rate anyway) to an
extent. A fair amount of cooling of the sparge water can occur so experiment
also with the sparge water temperature.
*****
Ken Schwartz
El Paso, TX
KennyEddy at aol.com
http://members.aol.com/kennyeddy
Return to table of contents
From: bob.sutton at fluordaniel.com (Bob Sutton)
Date: Tue, 17 Sep 1996 22:43:45 -0700
Subject: [none]
In HBD2178 KennyEddy obscurely stated in a very dated sense:
>Careful with that gypsum Eugene.
I believe that the gypsum problem will go away when you set your controls
for the heart of the hops (an equally obscure reference). Go figure.
Bob
Fruit Fly Brewhaus
Yesterdays' Technology Today
Return to table of contents
From: Jeff Renner <nerenner at umich.edu>
Date: Tue, 17 Sep 96 23:11:01 -0400
Subject: WHC score sheet horror
Kit Anderson referred folks to my post on JudgeNet Digest. For those
who don't have access to it, here it is:
I've just sent the following to the World Homebrew Contest people.
Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu
- -=-=-=-=-=-=-=-=-=-=-=-=-
Kate Begley
Co-Director, World Homebrew Contest
Boston Beer Co.
30 Germania St.
Boston, MA 02130
Dear Kate
I have just received my score sheets, T-shirt and hops from the 1996
(or
has it become the 1997?) World Homebrew Contest. In passing, I must
note that the hops pellets feel extremely crumbly through the
packaging.
However, it is the scoring and score sheets about which I am writing.
I have been a homebrewer for well over 20 years, a beer judge for about
10 years, a BJCP judge since 1991, and hold the BJCP rank of Certified
Judge. I participate in ongoing judging improvement programs such as
the Beer Judge Calibration Project and the Internet's Judge Net Digest.
I think I know beer and beer judging.
Last year, I entered a beer in WHC that I thought had (and still think
has) commercial potential, a variation on the classic Belgian Wit with
fresh ginger substituted for the lactic acid tang, and with coriander,
cardamom and grains of paradise. (As a matter of fact, I wonder if it
helped inspire the Sam Adams Summer Wheat with lemon and grains of
paradise). This "Ginger Wit" is very popular with beer drinkers and
non-beer drinkers alike, a light, refreshing beer with a good balance
of
components and a nice summer cooler. It scored a 43 in the Michigan
State Fair from BJCP National judges, and I was pleased to receive
three
highly perceptive and informative score sheets from WHC with scores in
the upper 30's, with full comments in all categories.
I entered this year's batch (which scored 41 in the State Fair, again
from a BJCP National judge) in the WHC with high hopes that it might be
a longshot. After two months, I received back the worst score sheets
(enclosed) that I have ever seen! I don't mean merely that I strongly
disagree with the 26/27 scores, although I do. I mean the quality of
scoring. The two judges (both "Experienced") had but one written
comment between them, under aroma - "Spruce/SO2." Spruce? SO2? Not
in this beer! What about ginger? Or the orangey coriander? Or the
Belgian nose from the Brugges yeast? What beer were they tasting? I
can't even begin to comment on the point breakdown except to note, for
example, that allotting one point of three possible for hops is
meaningless in a wit, where hops are simply not perceptible. And to
deduct for clarity when a wit is expected to have a haze? The point
allocations were identical in all but one sub category, leading me to
think that they copied one another.
I know that it is difficult to judge specialties that are not a classic
style, and that the score sheet does not lend itself to them, but did
these guys have a clue? Did they know what a wit tastes like enough to
judge a variation of it? Do they know what coriander smells like?
Have
they even ever had a Canada Dry ginger ale? I'm afraid that,
metaphorically speaking, they couldn't find their derrieres with their
hands tied behind their backs. I suspect that if they do know beer
judging, they simply had judged too many beers to be at all perceptive.
They still should have written some kind of comments. Were they give
any kind of direction?
Our club, the Ann Arbor Brewers' Guild, organizes three competitions
per
year - the Michigan State Fair, the regional "Taste of the Great
Lakes",
and the national "Mazer Cup" mead competition. I have seen first hand
how it can be difficult to get qualified judges, and not overtax them
with flights that are too large. Our solution has been to judge over
several days, or even over several weeks if necessary, even if it means
a delay in results. Furthermore, we always pair well experienced
judges
with less experienced ones, which helps in quality judging and helps
develop judging skills. I realize that the WHC is an order of
magnitude
larger, but it is still essential to maintain quality of judging.
Once again, I want to emphasize that it is not the scores that bother
me
nearly as much as the horrible quality of the score sheets, which is
insulting. I hope you can find a way to eliminate such judging in the
future.
Sincerely
Jeff Renner
cc: Judge Net Digest
Return to table of contents
From: Greg Pickles <gregp at wolfenet.com>
Date: Tue, 17 Sep 1996 20:35:41 -0700
Subject: re: cane sugar
AlK writes:
>>I've searched the archives and they do indicate that sucrose
>>(tablet sugar) is derived from sugar beets.
>
>In europe. In the US it's virtually (if not all) from cane
>sugar. Both cane and beet sugar are almost 100% sucrose (table
>sugar).
According to the National Agricultural Statistical Service of
the US Department of Agriculture, in 1990 3,004,000 tons of
sugar were produced from cane in the US and 3,809,000 tons were
produced from beets. (See
http://www.mannlib.cornell.edu/data-sets/specialty/91006/ for
details.) I can attest to the fact that we grow a lot of
sugar beets in the US because years ago when I frequently drove
through the Salinas valley of California to visit my in-laws, I
occasionally got stopped at a railroad grade crossing for half
an hour or more while a train hauling nothing but sugar beets
went by. I strongly suspect that we don't export all that beet
sugar to Europe. As far as I have been able to determine, from a
chemical or brewing standpoint, beet and cane sugar are
virtually indistinguishable so it's really a moot point
from which source your sugar comes.
Greg Pickles
Return to table of contents
From: Bret Bartlett <bbartlet at value.net>
Date: Tue, 17 Sep 1996 20:34:14 -0700
Subject: Pete's Wicked Ale Clone
I recently checked around for a recipe to re-create the taste of Pete's
Wicked Ale. I found just short of a million, and each claimed to be the
best. Is there anyone out there who can objectively tell me the
ingredients for a recipe that will taste very close to Pete's Wicked
Ale? Thanks in advance.
- -Bret Bartlett
Return to table of contents
From: Spencer W Thomas <spencer at engin.umich.edu>
Date: Wed, 18 Sep 1996 01:11:34 -0400
Subject: Re: Imperial gallon vs. US gallon
Don writes:
> USgal * 0.833 = Imperialgal
> Imperialgal * 1.201 = USgal
Much closer than 4/5 and 5/4 are 5/6 = 0.833... and 6/5 = 1.200
=Spencer Thomas in Ann Arbor, MI (spencer at umich.edu)
Return to table of contents
From: Geoff Bagley <geoff at gcbagley.demon.co.uk>
Date: Wed, 18 Sep 1996 10:26:35 +0100
Subject: Hop filters.
At the start of the copper (kettle) boil, just as the wort begins to
boil, I always skim off the coagulated scum which floats up to the top
of the wort. This means less work for the hop filter bed when I
eventually run off the boiling wort into the fermenter two hours later.
I no longer use hop bags, but use flower hops (NOT pellets) floating
loose in the copper.
I have a secret weapon to prevent the hops from clogging the output
tap/spigot.
I take a small sheet of stainless steel gauze, (taken from a kitchen
sieve) about the size of a bank-note, and roll it up like a cigar.
I place this filter into the inside of the output tap/spigot of the
copper (BEFORE FILLING IT!). This is a very good hop filter, and I get
nice clean wort.
The "copper" is really plastic, a 5 gallon (UK) "Bruheat" boiler.
My brew is a traditional english ale with Maris Otter pale malt,
Fuggles (bittering) and Goldings hops (aroma), and O.G. 1044 .
My yeast is a proffessional Burton (top fermenting) yeast obtained from
a local real-ale brewery.
Keep brewing,
Geoff Bagley,
Malvern, Worcs. U.K.
Return to table of contents
From: Andy Walsh <awalsh at crl.com.au>
Date: Wed, 18 Sep 1996 21:26:09 +1100
Subject: Copper & oxidation
Al K. doubts my input on copper causing oxidation:
AlK>What's your source on this information? I am extremely skeptical.
Well, don't forget you asked for it!
I'll start by quoting Charlie Bamforth of the Research Department of
Bass(1):
"Clearly the elimination of superoxide, but especially peroxide and
metals, will be of singular benefit to the shelf life of small-pack
beers...Above all, traces of metals such as copper and iron should be
eliminated at all stages...Only when ground-state oxygen is activated to
superoxide and beyond is it able to cause damage."
AlK>Hogwa... er... I disagree. Billions of gallons of beer has been
AlK>made in copper kettles and mash tuns.
Narziss (Weihenstephan) says (3):
"Metals catalyse oxidations. The replacement of copper or mild steel by
stainless steel has minimised this factor, although the effect of
cleaning agents on metal surfaces should not be neglected."
(I presume "cleaning agents" refers to the practice of eliminating the
oxide layer to minimise Cu++ and Fe++ pickup.)
The negative effect of copper on beer flavour stability is one reason
for the global switch to stainless steel. Technology does not remain
stagnant. Most copper seen in modern breweries is for cosmetic reasons.
That copper boiler you see is more likely to be of stainless steel with
a copper hood.
AlK>I've never had a problem with any of my beers that can be attributed
to copper.
I think you should rephrase that to, "I've never had a problem with any
of my beers that I have attributed to copper."
I personally think that the hysteria attributed to HSA and oxidation is
an over-reaction from a homebrew perspective. However, if one wants to
be really anal about oxidation (like being scared of fermenting in
plastic or storing beer in PET bottles), I think it would be consistent
to elimininate what is largely believed to be a major source of
oxidation in beer (1,2,3,4). Charlie Bamforth's experiments show that
introducing Cu++ (1ppm) to a 275ml bottle of beer causes more carbonyl
compounds than introduction of 10ml air! (1). This trend has been
confirmed in later studies (2,4).
The one benefit copper is said to have on beer flavour is that of
scavenging undesirable sulphury compounds (5).
I'll post a follow-up containing the overall theory.
Andy.
References:
(1) CW. Bamforth, R. Parsons. "New procedures to improve the flavor
stability of beer". Journal of the American Society of Brewing Chemists.
1985. 43. pp 197-202.
(2) CW. Bamforth, RE. Muller, MD. Walker. "Oxygen and oxygen radicals in
malting and brewing: a review". Journal of the American Society of
Brewing Chemists. 1993. 51. pp 79- 88.
(3) L. Narziss. "Centenary Review. Technological factors of flavour
stability" Journal of the Institute of Brewing. 1986. 92. pp 346-353.
(4) AJ. Irwin, RL. Barker, P.Pipasts. "The role of copper, oxygen, and
polyphenols in beer flavor instability". Journal of the American Society
of Brewing Chemists. 1991. 49. pp 140-148.
(5) RS. Thorne, E. Helm, K. Svendsen. "Control of sulphury impurities in
beer aroma". Journal of the Institute of Brewing. 1971. 77. pp 148-153.
- --
Andrew Walsh CHAD Research Laboratories
Phone (61 2) 212 6333 5/57 Foveaux Street
Fax (61 2) 212 1336 Surry Hills. NSW. 2010
email awalsh at crl.com.au Australia.
Return to table of contents
From: Andy Walsh <awalsh at crl.com.au>
Date: Wed, 18 Sep 1996 22:44:05 +1100
Subject: copper and oxidation - the theory
As molecular oxygen is a relatively stable molecule, it must be
converted to one of several radical or activated forms before it can
react with beer compounds to form stale flavours (mostly carbonyls).
This can occur by the acquisition of electrons from metal ions to form
superoxide (O2-), hydrogen peroxide (H2O2), the hydroxyl free radical
(OH*), and singlet oxygen. (These are in approximate ascending order of
reactivity).
It is not clear which of these forms are mainly responsible for beer
staling, but the important point is that ground state O2 must be
activated before it can commence. Transition metal ions can catalyse
this process. These exist in malt, but a substantial quantity can be
picked up from contact with metallics. The most important of these
metallic ions appears to be copper, since as little as 50ppb has been
shown to cause beer staling. Hence copper pickup should be minimised
throughout the brewing process, from mashing through to the finished
beer.
MASHING & LAUTERING
*******************
The main source of oxygen absorption during mashing is thought to be due
to the enzymic oxidation of polyphenols by peroxidase. This reaction is
generally limited by the availability of hydrogen peroxide in the mash.
This results in a reddening of the wort, and encourages the
precipitation of polyphenols with protein. (It is interesting that
unoxidised polyphenols play a major role in beer flavour stability, but
possibly a negative one in terms of astringency!)
High levels of copper in the mash (eg. due to a dirty copper mash tun)
can thus lead to higher levels of H2O2, and promote oxidation of
polyphenols. ie. HSA.
Malt peroxidase is stable with temperature. About 50% will survive 1
hour at 65C, and 45% at 76C.
BOILING
*******
Copper ions bind strongly with species such as polyphenols, melanoidins
and proteins. A substantial amount of Cu will precipitate in the hot
break (although polyphenol oxidation may already have occurred).
Melanoidins bind Fe and Cu very strongly, and it has been suggested that
this may contribute to dark beers' antioxidant properties.
FERMENTATION
************
Some metallics are absorbed by yeast during the fermentation, zinc in
particular.
POST-FERMENTATION
*****************
Minimisation of ground state oxygen at this stage is desirable, but the
negative effects of even quite substantial levels of O2 may be negated
if the O2 is not activated. Elimination of metal ions will enhance shelf
life, and is possibly more important than over emphasising low oxygen
levels.
References:
(1) CW. Bamforth, R. Parsons. "New procedures to improve the flavor
stability of beer". Journal of the American Society of Brewing Chemists.
1985. 43. pp 197-202.
(2) CW. Bamforth, RE. Muller, MD. Walker. "Oxygen and oxygen radicals in
malting and brewing: a review". Journal of the American Society of
Brewing Chemists. 1993. 51. pp 79- 88.
(3) L. Narziss. "Centenary Review. Technological factors of flavour
stability" Journal of the Institute of Brewing. 1986. 92. pp 346-353.
(4) AJ. Irwin, RL. Barker, P.Pipasts. "The role of copper, oxygen, and
polyphenols in beer flavor instability". Journal of the American Society
of Brewing Chemists. 1991. 49. pp 140-148.
- --
Andrew Walsh CHAD Research Laboratories
Phone (61 2) 212 6333 5/57 Foveaux Street
Fax (61 2) 212 1336 Surry Hills. NSW. 2010
email awalsh at crl.com.au Australia.
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From: George_De_Piro at berlex.com (George De Piro)
Date: Wed, 18 Sep 1996 08:19:00 -0700
Subject: RE: Brewers raking the sparge / Munich malt and Dunkles
Hello!
Jim Cave says that he's heard that some breweries rake their grain bed
at some point during the sparge, recirculate to achieve clarity, and
then continue to collect the runnings. He didn't know of any
examples, though.
Deschutes brewery, Bend OR, for one, does reset the grain bed once
during lautering.
----------------------
In a recent digest somebody (do you like how specific I can be?) said
that 100% Munich malt will make a Munich Dunkle. No, it won't. I've
done this to make a Maerzen. The beer will be too light for a Dunkle
(it's about right for a festbier).
All this talk of omitting roasted malts in Dunkles disturbs me.
Darryl Richman describes (quite nicely in his book, "Bock") the
German's use of roasted malts as "color malts." In SMALL quantities
roasted malts can/are used to deepen the color (and lower the mash pH)
of Munich beers.
I used 2 ounces of chocolate malt in a 5.5 US gal. batch of Dunkle
that was pretty good. The flavor contribution of 2 ounces of
chocolate malt was just about nil, and the color was right on.
Have fun!
George De Piro (Nyack, NY)
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From: RUSt1d? <rust1d at li.com>
Date: Wed, 18 Sep 1996 09:39:00 -0400 (EDT)
Subject: Re: Pro's homebrewing
>2. In My opinion this BOP process is anything but homebrewing... How does
>everyone else feel about this?
BOP's are the contract brewerys of the homebrewing community. Which leads
me to quote a funny quote I read in "Barley Corn" a brewspaper from
Frederick, MD:
"Contract brewing is the cocaine of the beer business. Those who do it,
deny it. Then they claim they have it under control. Finally, they say
it's okay in small amounts." - Paul Shipman, President, Redhook.
John Varady
Boneyard Brewing Co.
"Ale today, Gone tomorrow"
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From: Ken Sullivan <kj at nts.gssc.com>
Date: Wed, 18 Sep 1996 08:18:06 -0600
Subject: Drill bits vs. stopper sizes
Hi all, does anyone out there have a table which correlates
rubber stopper sizes with hole sizes for the purpose of
selecting the proper drill bit??
thanks, kj
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From: Special Events <spevents at postoffice.ptd.net>
Date: Wed, 18 Sep 1996 10:54:04 +0000
Subject: Homebrew Competition
Dear Homebrewer,
Following are the dates of the Great Brews of America Classic Beer
Festival. Anyone wanting information, please mail me at
spevents at prolog.net or call 717-722-9111 Ext. 815. I am also looking
for AHA certified judges for the homebrew competition, as well as
competitors. If anyone is interested, I would love to hear from you.
Homebrew Competition applications are also available on our web site
http://www.splitrockresort.com. I look forward to heafrom you. Happy
Brewing!
Fifth Annual Great Brews of America Classic Beer Festival
at Split Rock Resort, Lake Harmony, PA
November 23 & 24, 1996
Homebrew Seminar Day & AHA Homebrew Competition
November 22, 1996
Cheers!
Melissa Simock
Special Events Coordinator, Split Rock Resort
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From: STURM <jsturm at eagle.cc.ukans.edu>
Date: Wed, 18 Sep 1996 10:05:52 -0500 (CDT)
Subject: [none]
- ------------------------------
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From: Derek Lyons <elde at hurricane.net>
Date: Wed, 18 Sep 1996 08:16:30 -0700 (PDT)
Subject: Re: HBD buyers co-operative
At 01:52 PM 9/17/96 -0600, you wrote:
>I was wondering why with over 3800 members the HBD users haven't
>considered getting together to for a non-profit buying co-operative for
>home brew supplies such as grain, hops, carboys, equipment and extracts
>etc ? Surely with such a large group we could negotiate significant
>discounts with suppliers ? Any thoughts / comments ?
>
>Ian Smith
>
Who is going to research, catalog, recieve payment, order, receive,
warehouse, label, pack, ship and track all those items? Will we actually
save money when shipping is considered in?
Gen up a set of numbers and lets see what they say.
Derek
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From: "David R. Burley" <103164.3202 at CompuServe.COM>
Date: 18 Sep 96 12:33:25 EDT
Subject: Alcohol/flame sterilant
Brewsters:
I got awfully nervous reading Tim Martin's method of sterilizing using grain
alcohol at the mouth of his carboy and then lighting it. Alcohol and air in the
correct ratio are explosive. I suggest you stop flicking your Bic. Also,
"sterilizing" by burning is probably not doing anything since most of the heat
is going up. I suggest you stick with conventional sterilants like bleach
followed by boiled hot water in three rinses. It works fine. Let beer's big
brother cool some other flames.
- -------------------------------------------------------------------
Keep on brewin'
Dave Burley
Kinnelon, NJ 07405 USA
103164.3202 at COMPUSERVE.COM
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From: cburns at spider.lloyd.com (Charley)
Date: Wed, 18 Sep 1996 16:59:48 GMT
Subject: Korny Keg blowout
Please, no flames. I'm not associated with this company at all, I just thought
the collective might
be interested in what looks like a great deal. I live closeby and will go over
there Saturday and
pick up a half dozen.
5 gallon soda kegs for $14.50 and the guy has thousands of them. I have no idea
to what quality
level they are.
C&C Distributing
2718 Boardwalk
Placerville, CA 95667-4721
916-626-8223
email: 75322.2101 at Compuserve.Com
Talk to Matthew.
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From: TMCASTLE at am.pnu.com
Date: Wed, 18 Sep 1996 12:54:42 -0400
Subject: slow starting fermentation
Hey,
In HBD#2198 Scott Abene wonders about a slow start of Wyeast Thames
Valley (26h) compared to his normal 4-6 h for active fermentation to
proceed. Have I missed something? My ferments generally start
closer to the 15-20h mark. I always thought that was a good thing
that showed you aerated properly to get the beasties to divide and
conquer. Preparing for battle and all that. Are long lags good or
bad?
Yours brewfully,
Tom Castle in Kalamazoo (Michigan)
The Zen of Homebrewing
http://www.netcom.com/~tmcastle
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