HOMEBREW Digest #2917 Sat 02 January 1999
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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:
Acid Malt ("A.J. Zanyk")
Extended aeration of wort ("Fred L. Johnson")
hammermills (kathy/jim)
Re: More open fermenters (Jeff Renner)
Re: too much head stability (Jeff Renner)
NOT: Re: fruit flies in my science (Jeff Renner)
Mash Recirculation (Mearle Gates)
Re:Wyeast #3333 ("Rob Ball")
Fruit flies in the face of mill debate, hit it with ammonia (GuyG4)
Re: More open fermenters (Rod Prather)
Re: Danger from too much dissolved O2 in wort? (Scott Murman)
Re: Cock ale (Scott Murman)
HONEY info on the web (ALAN KEITH MEEKER)
NEW : Bonafied Beer Styles Page (Alan McKay)
Re: More open fermenters (Jeff Renner)
re: small fermenters (Richard Gardner)
DON'T AUTOCLAVE CLOSED CONTAINERS! (ALAN KEITH MEEKER)
inexpensive scales (ALAN KEITH MEEKER)
Strike procedure and denaturing enzymes ("George De Piro")
DO and Yeast/Hardness Paradox (AJ)
steam RIMS (Kyle Druey)
Beer is our obsession and we're late for therapy!
Enter The Mazer Cup! _THE_ mead competition.
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----------------------------------------------------------------------
Date: Fri, 01 Jan 1999 08:31:56 -0500
From: "A.J. Zanyk" <ajphoto at columbus.rr.com>
Subject: Acid Malt
Acid Malt
We recently got bag of Acid Malt. A number was accidently
transposed on our
order and return shipping costs made it easier just to keep it.
Now the question
is what to make from it. If I understand correctly Acid Malt is
primarily used to
compensate for carbonate waters. Could it be used to provide the
lactic
properties in let's say - a Belgian White, in more moderate
water? I have been
thinking about making another Hoegaarden/Celis style. What would
be the result
if I used the Acid Malt in place of the Pilsner Malt.
A.J. Zanyk
SODZ Brewclub
&
Goodale Homebrewing Supply
Columbus, Ohio
Return to table of contents
Date: Fri, 01 Jan 1999 09:23:55 -0500
From: "Fred L. Johnson" <FLJohnson at worldnet.att.net>
Subject: Extended aeration of wort
To the collective:
We all know that yeast growth is required is many (most) homebrew
settings. Many homebrewers don't pitch even close to the ideal amount of
yeast, so the general recommendation is to aerate well to permit the yeast
to grow to sufficient quantities to do a decent job of fermenting. The
challenge is to get enough oxygen in to allow this, but because only a
small fraction of air is oxygen, there is a limit to the amount of oxygen
dissolved in wort when saturated with air. Some homebrewers (and
commercial brewers) get around this limitation by pushing in purified
oxygen. I believe commercial brewers inject the oxygen in-line as the
wort leaves the chiller and enters the fermentor. Homebrewers typically
oxygenate with an airstone using short bursts. As Dave Humes recently
reminded us in his post to the HBD, the homebrewer is usually instructed
by the gurus to not overoxygenate as high concentrations of O2 may be
toxic to the yeast.
QUESTION for the collective: Rather than oxygenate with purified oxygen,
why should not homebrewers (and commercial brewers for that matter) simply
aerate intermittently or continuously with an aquarium pump for an
extended period of time (hours)?
As I recently posted to the digest, I intend to start aerating my starters
this way, decanting off the flocculated yeast. (Additional comments are
greatly appreciated.)
The following are related questions that should only be dealt with if what
I've suggested above has any merit:
1. I assume there a point at which further aeration would produce too much
yeast growth and the inevitable off-flavors associated with it. How does
one determine the optimal amount of aeration, assuming this could be
different for different batches?
2. If the yeast starters are grown in the constant presence of oxygen, I
assume that the yeast will eventually stop growing when another growth
factor, nutrient, etc. becomes depleted. Will such yeast ferment beer any
differently than yeast cultured more conventionally?
- --
Fred L. Johnson
Apex, North Carolina
USA
Return to table of contents
Date: Fri, 01 Jan 1999 10:01:14 -0500
From: kathy/jim <kbooth at scnc.waverly.k12.mi.us>
Subject: hammermills
Matthew Hammer writes about pulverizing grain to flour to get maximum
extraction. Years ago we toured the Weidmer? Brewing in Portland Oregon
and they did a number of contract brews. Anyway my foggy memory recalls
that for brews where cost was the major consideration, they hammermilled
to flour, mashed somehow and relied on a centrifuge to extract the bits
of husk.
Lacking an efficient centrifuge at home, I run my Corona at normal malt
spacings and sacrifice a bit of efficency. Squeezing pennies is not
worth it.
For more efficency, easier milling and less dust I do temper my malt
with 2 T/lb water, stir and let stand in a covered container for 30'.
As I written for the umpteenth time on the HBD, this produces more
fines/flour and a more intact husk.
Happy Brew Year Number 1999 cheers, jim booth, lansing mi
Return to table of contents
Date: Fri, 1 Jan 1999 11:01:28 -0500
From: Jeff Renner <nerenner at umich.edu>
Subject: Re: More open fermenters
Rod Prather <rodpr at iquest.net> wrote
>Remember that most
>great French bread bakeries NEVER add yeast, they rely totally on
>the yeast soup floating in the bakery.
One of the wonderful things about HBD is that there are experts on just
about any subject you mention - refrigeration, hydrology, metalurgy,
computers, and so on. This not only is a treasure trove of information,
but it keeps you honest when you say something. I know I've had assertions
I made corrected.
Here you've hit on a subject that I may humbly offer myself up as resident
expert - French bread. As the owner of a self-proclaimed such "great
French bread bakery," although not one in France, of course, and as an
amateur historian of bread and baking, I can offer some information on this
subject.
French bakeries do not use this method for leavening their bread. Most
modern bakeries use culture yeast, but I imagine you are referring to
traditional bakeries. These use what we call in the US sour dough,
although typical French cultures do not produce particularly sour bread.
Such a culture is a stable mix of wild yeast(s) and Lactobacillus spp. and
perhaps other bacteria. Bakers introduce this to their bread dough either
by adding some dough from the day before or by adding a portion of a
separate culture going which they feed regularly. They do not make up
dough and rely on the whims of "yeast soup floating in the bakery" to
introduce this critical component to their bread. It would be far too
unreliable and slow. This is a method of inocculating a new culture, and I
have used it for making a three day fermented pumpernickel.
If you are interested in more information, check news:rec.food.sourdough
and the sourdough FAQ at
http://www.nyx.net/~dgreenw/sourdoughfaqs.html.
Dan McConnell of the Yeast Culture Kit Co. has available a French sourdough
culture that I obtained from a friend who brought it back from Paris. This
culture is from the Poilane bakery that was featured in a cover story in
Smithsonian a few years ago. The YCKC web site
http://oeonline.com/~pbabcock/yckco/yckcotbl.html has it and also my
directions for using it. BTW, I make no money from this and Dan makes
precious little.
You can also get a free dried Oregon culture from Carl (last name?), whose
family brought it to Oregon in the last century. I think the sourdough FAQ
has his address, or someone at r.f.s could steer you. Also, Sourdough
International (don't have the URL but again, r.f.s. or the FAQ should have
it) sells many cultures from different parts of the world such as Russia,
Egypt, France, etc.
Now back to your regularly scheduled fruit fly debate.
Jeff
-=-=-=-=-
Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu
"One never knows, do one?" Fats Waller, American Musician, 1904-1943.
Return to table of contents
Date: Fri, 1 Jan 1999 12:20:28 -0500
From: Jeff Renner <nerenner at umich.edu>
Subject: Re: too much head stability
Kevin TenBrink <zzymurgist at yahoo.com> complains that his all grain beer's
head won't collapse.
We should all have such a problem! A few ideas and some other questions
the post raises.
George Fix has reported that a 158F rest results in better foam stand.
Since you are conducting your mash at nearly such a temp, you may be
producing lots of whatever is responsible. Also, I notice that plastic
judging cups always have better foam stand than my glasses, and I wonder if
something in my glasses (washed in a dw with softened water, Cascade and no
rinse agent) is the reason. How are you washing your glasses?
High hop levels also contribute to stability. BTW, what style is this?
It's fermented like a lager although not lagered in a classic manner (32F
for more than two weeks). Maybe a strong lager like some of the N.
European super premiums such as Carlsberg Elephant? Seems mighty bitter.
I figure 80 IBU just from the 2 ozs Nugget 12.3 AAU 60 mins. What do you
figure is its bitterness level? How would you describe this beer? Of
course, it doesn't have to be any style at all except yours.
I would have expected a higher FG with that high mash temp. Any idea why
it finishes with 85% apparent attenuation? Lots of oxygenation? A potent
beer!
Jeff
-=-=-=-=-
Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu
"One never knows, do one?" Fats Waller, American Musician, 1904-1943.
Return to table of contents
Date: Fri, 1 Jan 1999 12:21:37 -0500
From: Jeff Renner <nerenner at umich.edu>
Subject: NOT: Re: fruit flies in my science
Dave Sapsis <DAVE_SAPSIS at fire.ca.gov> writes of:
>my 1994 barleywind ...
I like that term! Sounds like what my wife complains of an hour or two
after I've had a few homebrews. :-)
Jeff
-=-=-=-=-
Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu
"One never knows, do one?" Fats Waller, American Musician, 1904-1943.
Return to table of contents
Date: Fri, 01 Jan 1999 09:32:49 -0800
From: Mearle Gates <mearle at orcalink.com>
Subject: Mash Recirculation
I've got an idea for a RIMS variation, but need help in locating
suitable parts. I want to simply pump from the mash tun up to a kettle
sitting on an electric heating element. A gravity oveflow line would
then take the wort back to the top of the mash. The kettle heating
element needs to be turned on and off by a thermostat that detects the
wort temperature in the kettle. When 158F (or whatever) is reached the
heater would cut off. The pump could continue running and recirculating.
I have a pump, a heating element, and a kettle, but not the temp sensor
or controller. Any suggestions?
Mearle
Return to table of contents
Date: Fri, 1 Jan 1999 13:51:20 -0500
From: "Rob Ball" <robball1 at earthlink.net>
Subject: Re:Wyeast #3333
Hello,
I have used 3333 twice,it's for a more traditional type German
wheat(weizen).It has less clove flavor than the #3068 and has a nice
crisp and tart with some friuty-sherry like palete,best way I can
describe it.Nice results,high flocculation,70-76% attenuation. Nice in
a Dunkel also good luck hope this helps.
Gotta go gotta brew..
Take Care
+++++++++++++++++++++++++++++++++++++++
Rob Ball
robball1 at mail.earthlink.net
Way to old to grow up now!!
+++++++++++++++++++++++++++++++++++++++++
Return to table of contents
Date: Fri, 1 Jan 1999 14:18:39 EST
From: GuyG4 at aol.com
Subject: Fruit flies in the face of mill debate, hit it with ammonia
To the collective:
1) My fruit flies all die of botulism. I can tell because they stick to the
Cl*****st strips. Or at least they did once.
2) Optimum crush of fruit flies can only be achieved by the Glatt mill.
3) On a somewhat serious note, those of us reading hbd regularly note that
cleaning comes up from time to time. I use ammonia for my carboys...yes, yes,
there are substantial safety concerns using ammonia and chlorine based
cleaners in the brewhouse, anyone attempting this must rinse completely and
watch yourself very very carefully, mixing bleach and ammonia makes a deadly
gas!!!!
But, nothing cleans glass like dilute ammonia and water. Since my brewshop
dropped b-brite in favor of a very expensive cleaning product which, IMHO,
doesn't perform very well, I've been using 1 cup ammonia in 5 gallons of water
for my carboy soak, followed by a triple rinse to no ammonia odor (very low
odor threshold), followed by iodophor solution (corked) in prep for the next
brewday. The carboys sparkle, no gas discharge I've been able to sense with
my nose, and my beer still tastes good. I'd recently hit my kegs with ammonia
solution (again, quite dilute) and they got really clean, inside and out, with
minimum effort and maximum result. The ammonia bottle says "safe for all
washable surfaces", so I gave it a go.
But, a couple of questions for those who might have an opinion:
1. Is there any long-term impact to stainless steel from ammonia based
cleaners like there is with the chlorinated cleaners?
2. Does the no-chlorine rule with ammonia apply to other halogens,
specifically iodine based sanitizers?
3. Any problems with ammonia based cleaners and plastic hoses?
Happy new year from:
Guy Gregory
GuyG4 at aol.com
Lightning Creek Home Brewery
Spokane, WA
Now lagering for spring.
Return to table of contents
Date: Fri, 01 Jan 1999 15:08:25 -0500
From: Rod Prather <rodpr at iquest.net>
Subject: Re: More open fermenters
I was, of course, referring to old traditional hand bakeries. They did not, and
I believe some still do not, use cultured yeast. After checking for the
reference I find I can't find it.. I believe this concept came from a
discusion on the old FIDONET BBS network on the International Cooking Echo
about French bread bakeries. One person involved was an English chef working in
Paris. True, they don't actually get the yeast simply by setting the dough out
to be inocculated by the air, my error. Since they use a running sour dough
the yeast mix tends to be a work in progress and the bakery tends to harbor the
yeast culture used in the breads. So available are these yeasts that new
starters can be made from airborne yeast simply by setting a starting substrate
out for a yeast collection although I doubt this is frequently done. I will
keep my eye out for a reference. I still think it was James Beard.
Jeff Renner wrote:
> Rod Prather <rodpr at iquest.net> wrote
> >Remember that most
> >great French bread bakeries NEVER add yeast, they rely totally on
> >the yeast soup floating in the bakery.
> French bakeries do not use this method for leavening their bread. Most
> modern bakeries use culture yeast, but I imagine you are referring to
> traditional bakeries.
Return to table of contents
Date: Fri, 1 Jan 1999 12:26:28 -0800 (PST)
From: Scott Murman <smurman at best.com>
Subject: Re: Danger from too much dissolved O2 in wort?
> I started oxygenating with pure O2 several months ago, mainly to
> shorten my brewing hours and also to insure that adequate levels of
> dissolved O2 are provided. I've become somewhat concerned that I
> have little control over DO levels since it's not something that I
> can measure. From what I've read for normal gravity worts, there's
> little advantage to be gained by introducing any more DO than about
> 25% of the saturation amount. BTW, what is the saturation amount?
>
> Dave Humes >>humesdg1 at earthlink.net<<
I plotted out the data that A.J. DeLange posted awhile back for
saturation of wort (water) with pure O2 and air.
http://www.best.com/~smurman/zymurgy
Bottom line was about 60 secs of pure O2 gives 100% saturation.
-SM-
Return to table of contents
Date: Fri, 1 Jan 1999 12:37:15 -0800 (PST)
From: Scott Murman <smurman at best.com>
Subject: Re: Cock ale
> I have several recipes for "cock ale" in a couple of my historical books..
> Cindy Renfrow's book _A Sip Through Time_ has four of them, dating from 1550
> - 1780. This disgusting concept usually had a recipe of something like 2-10
> gallons of fermenting ale, and a dead plucked chicken. Wheee..
>
> badger
I once again submit that the Big Brew batch should be Cock Ale.
Frozen friar parts allowed. Extra credit for those groups that start
with a live chicken, and can de-feather and sparge at the same time.
The folks at Guinness records couldn't possibly refuse. It would be a
record to stand for all time.
-SM-
Return to table of contents
Date: Fri, 1 Jan 1999 15:56:46 -0500 (EST)
From: ALAN KEITH MEEKER <ameeker at welchlink.welch.jhu.edu>
Subject: HONEY info on the web
I have had several requests for links to honey/mead info.
The National Honey Board has a lot of material on honey. Topics include -
shelf life, proper storage, crystallization, chemical composition,
physical characteristics, carbo analyses, color, floral sources, etc...
Their link is www.nhb.org. They also have a "honey hotline" for technical
questions at (800) 356-5941. In addition they also maintain a list of
AMERICA'S HONEY SUPPLIERS.
_______________________________________________________________________
Some mead links, some of which contain honey info:
//www.lallemand.com/brew/Mead/mead.html
//www.best.com/~davep/mme/contents.html
//realbeer.com/brewery/library/meadfaq.html
//www.atd.ucar.edu/rdp/gfc/mead/danspaper.html
//www.atd.ucar.edu/rdp/gfc/mead/rcdyeast.html
________________________________________________________________________
These ought to get you started. There is also the Mead Lover's Digest
which is the mead equivalent of HBD, run by Dick Dunn. Subscriptions at
mead-request@ talisman.com
Happy Hunting!!
- ------------------------------------------------------------------
"Graduate school is the snooze button on the alarm clock of life."
-Jim Squire
-Alan Meeker
Johns Hopkins Hospital
Dept. of Urology
(410) 614-4974
__________________________________________________________________
Return to table of contents
Date: Fri, 01 Jan 1999 17:16:31 -0500
From: Alan McKay <amckay at mail.magma.ca>
Subject: NEW : Bonafied Beer Styles Page
Bonafied Beer Styles
This page is being put together with the single goal of
providing homebrewers with a bonafied beer (or beers) against
which they can compare their own brews to tell if they are
close to the real thing as far as style goes. We are looking
for a lot of input from the Internet on this one, but at the
same time we are going to be extremely strict about all
submissions. If you can't prove to us why a particular beer
should be accepted as a true representative of the style,
then we can't put the submission on the page. If we do not
take this approach, it will defeat the very purpose of the
page in the first place, and will not provide any sort of
usefulness at all to the homebrewing community. So for example,
if you've never been to Cologne and drunk the real Klsch, or
if you've never been able to obtain real imports at your local
Beer Store, please don't submit something which you think is a
good representative of the style. I don't care how many BJCP
points you have, if you've never tasted the Real McCoy, then
there's no way you can know what the beer tastes like. So please
don't take it personally if we decide not to use your
submission.
It's not yet linked into the main pages, so please visit the
following page if you'd like to have a look, or make a
submission :
http://www.magma.ca/~bodnsatz/brew/styles/
This page is in it's infancy at the moment, but I'm hoping it
will only take a few weeks to turn it into an extremely useful
resource.
If you are making a submission, please let me know what area of
the world you are in so that I can include that information on
the site (city, country) All submissions used will include the
name and contact information (Email) of the person providing the
submission. I'll also want to know what qualifies you as being
able to identify a beer of this style.
I should also note that I'm not going strictly with the AHA
styles guidelines on this one. For one thing, most of the
so-called "American" styles won't be found on this page (at
least not initially). Though what exactly should be included
is certainly open for discussion.
cheers,
-Alan
- --
"Brewers make wort, yeast makes beer"
- Dave Miller's Homebrewing Guide
http://www.magma.ca/~bodnsatz/brew/tips/
Return to table of contents
Date: Fri, 1 Jan 1999 17:21:48 -0500
From: Jeff Renner <nerenner at umich.edu>
Subject: Re: More open fermenters
At 3:08 PM -0500 1/1/99, Rod Prather wrote:
>Since they use a running sour dough
>the yeast mix tends to be a work in progress and the bakery tends to
>harbor the
>yeast culture used in the breads. So available are these yeasts that new
>starters can be made from airborne yeast simply by setting a starting
>substrate
>out for a yeast collection although I doubt this is frequently done.
It probably is true that each bakery may have a unique mix of flora in the
air, and this probably does affect the levain (starter) and vice versa. I
suspect that the starter I have from Poilane's in Paris has changed since I
got it and has become adapted to my techniques for keeping and feeding it,
etc. Climate evidently also plays a part. SF sourdough, for example, is
reportedly not maintainable by ordinary means (just feeding it) outside of
the Bay area. But I do have several cultures that have maintained separate
identities - one is more sour than another, suggesting that my resident
flora have not overwhelmed the makeup of the cultures. For my production
French bread, I use normal cultured bread yeast, not a culture, but I use
cultures for special breads. Happily, none of this has influenced the
quality of my brewing, which I conduct a few feet from the bakery.
Jeff
-=-=-=-=-
Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu
"One never knows, do one?" Fats Waller, American Musician, 1904-1943.
Return to table of contents
Date: Fri, 1 Jan 1999 23:44:18 -0000
From: Richard Gardner <rgardner at mwr.is>
Subject: re: small fermenters
I use 1 gallon (or 4 liter) glass apple juice/cider jugs. They're cheap at
less than $2 US filled with apple juice. I've seen them with 2 size mouths,
1.25" or 1.5" - I prefer the larger size. Perfect for trying out various
meads. I've had up to 5 different meads going at once, which I wouldn't do
with a 5+ gallon carboy.
I think excessive headspace (5 gal carboy) would be a problem if you are
doing a 2-stage fermentation. Some here just do a single stage (AlK I
believe), in which case if you do this in a closed fermenter (carboy and
airlock)
Brewing at 64N, 22W, 2822 miles bearing 036 from Jeff Renner, and 26
degrees F warmer.
Return to table of contents
Date: Fri, 1 Jan 1999 19:08:00 -0500 (EST)
From: ALAN KEITH MEEKER <ameeker at welchlink.welch.jhu.edu>
Subject: DON'T AUTOCLAVE CLOSED CONTAINERS!
Brad Miller wrote:
>> In the last post somebody was giving advise on autoclaving and I
>>thought it important to point out that his advise was wrong. I work in
>>a genetics lab and frequently autoclave various items. Granted I use a
>>frickin' huge Amsco autoclave but the principles are still the same.
>>You can autoclave closed containers or whatever you want. The only
>>things that matter are Time and Temp. If you are at a certain temp,
>>then you have to stay there for so long. The higher the temp the
>>shorter the time. As for pressure, this just alowes for higher temps.
>>Just thought that this error should be noted.
>>
YIKES!! It is dangerous to autoclave a closed container - DON'T DO IT!! I
too work in a lab and also use an AMSCO autoclave and in the AMSCO manual
it clearly states - in bold black font - to NOT autoclave closed
containers - containers with screw-top lids or crimped rubber closures
for example.
The AMSCO manual treats this as a safety issue and does not say whether it
impacts sterilization efficiency or not. I recall from my micro courses
that wet heat is more efficient than dry and that, in addition to safety
concerns, this is why you want to allow open exposure to the autoclave. I
only have one micro text here at the house but in the chapter covering
sterilization it supports this view -
"...generally dry heat requires more time than wet heat to kill..."
"The modern autoclave is, in principle, a
sophistocated pressure cooker with mechanisms for regulating steam
pressure and ensuring complete evacuation of air from the chamber. The
presence of air would allow an increase of pressure in the chamber without
a corresponding increase in temperature. Thus, it is important always to
check the temperature as well as the pressure because the latter is of
little or no significance in killing microbes. Superheated steam (dry
steam) is likewise unsatisfactory and kills at slow rates, similar to
those of hot air."
"The main reason for the great effectiveness of the autoclave as compared
to the hot air oven relates to the fact that heat coagulation of proteins,
including essential enzymes, occurs more readily under moist conditions
that in those which are dry. Release of the latent heat of vaporization by
steam condensing on organisms may play a role in the rapid killing."
"Contact With Steam: Dry micorganisms protected from contact with steam
(for example, within oil, occlusive wrappings, or containers of powder)
cannot reliably be killed by autoclaving."
-Microbiology (2nd ed) Nester, Roberts, Pearsall, and McCarthy.
In practice, we often use bottles with screw cap lids but we ALWAYS make
sure these caps are only on loosely, never fully closed. To do otherwise
is to risk explosions upon decompression.
Be careful out there!
-Alan
Alan Meeker
Johns Hopkins Sch. Med.
Baltimore, Md.
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Date: Fri, 1 Jan 1999 19:11:32 -0500 (EST)
From: ALAN KEITH MEEKER <ameeker at welchlink.welch.jhu.edu>
Subject: inexpensive scales
Another potential source for inexpensive scales is the neighborhood pawn
shop. Especially if the neighborhood is located in a city (drug trade) and
even more especially if the pawn shop is close to a teaching hospital or
research university! The prices can be cheap but of course - caveat
emptor...
-Alan
- ------------------------------------------------------------------
"Graduate school is the snooze button on the alarm clock of life."
-Jim Squire
-Alan Meeker
Johns Hopkins Hospital
Dept. of Urology
(410) 614-4974
__________________________________________________________________
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Date: Fri, 01 Jan 99 19:12:25 PST
From: "George De Piro" <gdepiro at fcc.net>
Subject: Strike procedure and denaturing enzymes
Hi all,
Steve Jones (you're not the one from that band Malcolm
McLaren organized in the 70's...nah, couldn't be) asks:
" if I might be denaturing
some of the the beta amylase enzymes when the grain first
hits the 164F+ water and maybe don't get as many
fermentables as a result. I do occasionally have a batch
that finishes with a higher than expected gravity, and maybe
this is a contributing factor."
Back to me:
Beta amylase does not survive long at temperatures over
70C (158F), but it does survive for a few minutes. The
temperature of the mash water drops pretty quickly once you
start adding the malt, so the majority of the grain is hitting the
water after it is below 70C. Given the fact that there is
excessive beta amylase in barley malt, you should have no
problems achieving well-attenuated beer with a strike heat
of 164F (73C).
If you are experiencing attenuation woes, you should
look at several things:
1. Do a forced ferment to see what the attenuation limit of the wort
will be.
2. Make sure you pitch plenty of healthy yeast and oxygenate well.
3. Make sure your mash thermometer is calibrated properly.
In case you do overshoot your target temperatures, it is handy to
know that at 70C beta amylase will survive about 10 minutes.
Alpha amylase is much more heat stabile, surviving through mash out.
Have fun!
George de Piro (Nyack, NY)
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Date: Fri, 01 Jan 1999 19:54:39 +0000
From: AJ <ajdel at mindspring.com>
Subject: DO and Yeast/Hardness Paradox
Dave Humes asked several questions about DO and yeast. One was what the
saturation level is. This depends on several factors. For worts of
normal gravity at room temperature, saturation is indeed about 8 mg/L.
If the wort is chilled, this number can go up substatially (over 10 mg/L
depending on the temperature.
The most important question was whether one can overdo oxygenation and
the answer is yes in the sense that there is an optimum level for each
yeast strain and gyle. There is, however, no textbook in which one can
find this level tabulated. This aside, it's pretty hard to overdo
oxygenation because if the wort loaded to above the saturation level the
O2 will generally escape to the ambient in short order if the wort is
underpitched and be consumed by the yeast in short order (half an hour)
if over pitched. The clear disadvantage of overoxygenation with high
pitching levels is that too many yeast cells will be produced resulting
in conversion of more wort nutrients than desired into yeast biomass and
growth phase metabolites rather than into alcohol, CO2 and tasty
fermentation phase metabolites.
I have never been able to kill yeast with oxygen even in experiments in
which I maintained several hundred percent of atmospheric saturation.
The cell counts just kept going up and up.
And yes, volumes have been written on this subject in this forum, in
Brewing Techniques and in the professional literature.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Chris Beadle wrote:
>I tested water with an aquarium water hardness test kit, which
>consists of
>sodium hydroxide and calmagite solution. EDTA color indicator is
then
>added drop by drop (mixing between each drop) until a color change is
>noted.
Starting with a nit: Chris apparently has the "Dr. Wellfish" kit in
which the EDTA is labeled "color indicator". The calmagite is, in fact,
the indicator. It forms a wine red complex with calcium and/or
magnesium. (it's blue when not complexed) and the EDTA is a chelant. As
EDTA is titrated into the sample it grabs (chela = claw) the Ca and Mg
away from the calmagite. When all the Ca and Mg are so bound the
Calmagite changes back to blue. Proper behavior of the calmagite, and
especially production of a sharp endpoint, require the pH to be within
certain bounds. This is the function of the sodium hydroxide. In better
kits, a buffer (usually organic) is supplied for this purpose though
sodium (or potassium) hydroxide are often also supplied to be used to
raise the pH of the sample to the point where Mg(OH) precipitates thus
making it possible to test for calcium only.
Now on to the meat, Chris's results:
>Tap water 150 ppm hardness
>Boiled 10 min (and cooled) 140 ppm (no obvious precipitate)
>Boiled 40 min (and cooled) 240 ppm (granular and thread like
white
>precipitates)
>The chemical analysis (Lake Huron water) lists the following:
>Mg 6.6 - 8.0 ppm, Ca 20 - 27 ppm, total hardness 96-104 ppm,
>non-carbonate
>hardness 21 - 46, and pH 7.2 - 7.6. These numbers are ranges for an 8
>month period.
The question concerns why boiling increased the measured hardness. Water
at the reported level of hardness, particularly where a substantial
fraction is non carbonate hardness, does not usually precipitate
anything and the 10 minute boil data (this kit is a drop count kit with
a precision of 10 ppm) is consistent with that, i.e. a 1 drop change is
not significant.
After 40 minutes of boiling a precipitate was observed and the hardness
increased 71%. The only explanation I can offer for this is that a great
deal of water was evaporated during this long boil i.e. about half of
it. Assuming for the moment that half is the right number and that non
carbonate hardness is about 30% of the total (45 mg/L at the outset) non
carbonate hardness would go to 90 mg/L and carbonate hardness to 2*105 =
210 for a total of 300. If 60 of the carbonate precipitated (leaving
carbonate at 150 which is roughly the magnitude of carbonate hardness
left after boiling and precipitation, we'd have the 240 Chris measured
but this is all speculation at this point. Only Chris can tell us
whether substantial water loss took place. If it didn't, this theory is
all wet. The next most obvious explanation is that the test kit was not
used properly. There are methods for checking on the accuracy of such
tests ("standard additions" or "spiking" as it is sometimes called) but
I'll not go into that unless requested.
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Date: Sat, 02 Jan 1999 05:14:35 -0800
From: Kyle Druey <druey at ibm.net>
Subject: steam RIMS
I have enjoyed reading Bill Macher's steam injected RIMS post.
>How delicate are these enzymes that we depend on anyway?
Not sure, but if a heating element surface if hotter than steam, then
you should have no problems. I don't no of any RIMSers out there that
have problems with conversion due to denatured enzymes. Someone last
year posted than they were getting 4 F/min ramp rates with their
prototype steam RIMS, instead of the usual 1 to 1.5 F/min.
I am tinkering with the idea of adding steam injection to my electric
RIMS. I think Walmart sells 6 qt cheapo pressure cookers for about $25.
Bill, keep us posted on your progress.
Word from the Midwest has it that Fouch is going to start manufacturing
and marketing a new piece of sparging equipment. He uses PVC tubing and
a condom and calls it a SLEEZYMASHER(tm).
Kyle
Bakersfield, CA
CA citrus crop is almost a total loss due to the freeze. Won't be able
to buy fresh oranges at the store until next year, and the price of
Chilean fresh fruit will skyrocket.
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