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HOMEBREW Digest #2952
HOMEBREW Digest #2952 Fri 12 February 1999
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:
denaturing/flaked barley/CaCl2/washing glasses/starters/nutrients/CO2 (BrewInfo)
Of course hot water freezes faster (Armin Ulrich)
Historic Porter/brown malt/Weyermann rauchmalt (Jeremy Bergsman)
Momilies keep rolling in.... (Jack Schmidling)
"alcohol tolerance" (Jim Liddil)
The Jethro Gump Report...part 1. ("Rob Moline")
The Jethro Gump Report...part 2 ("Rob Moline")
The Jethro Gump Report...part 3 ("Rob Moline")
Alcohol content and fortification (Rod Prather)
RE: Rod P.'s "Math challenge" ("S. Wesley")
re: bottler thingies (Mark Tumarkin)
Dispensing from kegs without a CO2 bottle / Y2KBW (Ken Schwartz)
dry hop with Fuggles ? (LEAVITDG)
Efficiency question: Am I getting enough out of the malt? (LEAVITDG)
Yeast Autolysis/Yeast Library? (Matthew Comstock)
Making candi sugar / beer stock (PAUL W HAAF JR)
Beer is our obsession and we're late for therapy!
Enter The Mazer Cup! _THE_ mead competition.
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----------------------------------------------------------------------
Date: Tue, 9 Feb 1999 18:00:05 -0600 (CST)
From: BrewInfo <brewinfo@xnet.com>
Subject: denaturing/flaked barley/CaCl2/washing glasses/starters/nutrients/CO2
More old, unanswered topics...
Steve writes:
>My question is about the initial mix of hot water & grain in
>the mash tun. I mash in a converted sanke keg by adding the
>strike water, heating it to strike temp, then pouring in the
>grain while stirring. I usually hit my mash temp within a
>degree , and don't seem to have any real problem with my
>brews.
>However, a fellow brewer asked me 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.
Enzyme denaturing is not instantaneous, but I would not be surprised
if you found a correlation between the higher FG beers and those
mashes that you mashed-in very slowly. Personally, I have not been
so blessed as you with hitting mash temps, so what I do is I heat
half of my strike water in my mash tun and half in my kettle. I
quickly dump all my malt into the mashtun and stir well. I then
add water from the kettle until I've hit my target temp. I always
make more water than I think I'll need and often I will use it.
Stirring the very thick mash I get with this dough-in procedure is
tough (esp since I do 1/2bbl batches & have used 46# of malt in a
single mash), but it's much easier to get the lumps out of the thick
mash than chasing them around a thin mash.
***
Darrell writes:
>Also, one local pub brewer suggeste puting the flaked barley into the
>mashtun when recirculating and sparging...ha anyone heard of this?
It depends on how long and at what temperature he recirculates. If
it is at 170F and for only 15 or 20 minutes, he/she is getting
starchy, wort. Flaked barley is mostly starch (and a lot of beta
glucans, by the way) and thus needs to be mashed as long (and maybe
even longer) than malted barley.
***
Domenick writes:
>Put a pinch of the CaCl2 on a plate and if it "melts" then you have
>the anhydrous. If it doesn't melt then you've got the dihydrate,
>CaCl2.2H20.
Not exactly... CaCl2 will keep attracting water in any form, anhydrous,
dihydrate, hexahydrate (CaCl2.6H2O)... Anhydrous, given time, will
attract water from the atmosphere and make dihydrate, which will then
continue to attract water and make hexahydrate...
Incidentally, a sealed container of CaCl2 will be mostly one form after
a while, but I believe that a pinch on a plate will be a mixture of
various forms. CaCl2 is extremely hygroscopic (attracts water) which
is why it is used for dessicants! If you buy some, make sure it comes
in a sealed package and store it in an airtight container. Take out
what you need, right into the scale, if you've got it and seal up the
remainder immediately. After weighing/measureing, you can allow it
to turn to soup... the ppm of Ca+2 and Cl- this blob will add will not
change.
>If you have the dihydrate then one gram contributes,
>Ca 72.1 and Cl 127.3
Yes, but more specifically, one gram of dihydrate CaCl2 in 1 gallon of
water will give you 72.1 ppm of Ca+2 and 127.3 ppm of Cl-.
***
Kevin writes:
>>>How are you washing your glasses?<<
>Hand wash with warm water (Lansing city) and palmolive dish soap,
>rinse and let air dry.
No, no, no! Never use soap on beer equipment or glassware. I recomend
washing soda (sodium carbonate). The second best choice is dishwasher
powder (usually mostly sodium carbonate). Avoid dishwasher powders
that contain sheeting agents ("no spots!"). Detergent good... soap bad!
Soaps will leave a film that kills your head retention.
***
Mike writes:
>I've been using yeast starters for all grain brewing. I'm getting
>conflicting info regarding them. Questions: 1). Am I supposed to decant most
>of the liquid in the yeast starter before pitching it into the wort? One
>author says to do this and just pitch the very bottom slurry. I've been
>pitching the entire yeast starter contents; and 2). What is yeast nutrient
>and what is yeast energizer? One brew shop sold me yeast nutrient which was
>supposed to be yeast skeletons (?) and yeast energizer which was a white
>powder (urea?). However, another brew shop sold me yeast nutrient which was
>a white powder (urea?) and yeast energizer which was yeast skeletons. Which
>brew shop has it right? Thanks.
1. Ideally, you would like to pitch the yeast when it is just past high
kraeusen... while it is still very active. This will give you the shortest
lag times and yeast with the highest level of glycogen (this is important
for a number of reasons... see the archives for a discussion). If you
wait until the yeast has all settled, this optimal time has long past.
What I do is allow the yeast in my starter to settle, timing it so that
I can pour off the spent wort the day before brewing and then add a small
amount of fresh wort. This means that I can make 2 or even 4 liters
worth of yeast starter, but then feed the slurry with only 500 ml of
wort the day before brewing. This way, I pitch a "large" starter but
only add 500ml of "foreign" wort to my batch.
2. Both brew shops might be right. I've found that various manufacturers
call their products different things. One companies "energiser" is
anothers "nutrient." Bottom line: a simple white powder is most likely
diammonium phosphate (DAP). This is best left for vintners. What you
want is a mixture of various nutrients, including vitamins and yeast hulls
(aka skeletons). This mixture will be tan and will not be all one "shape"
or colour (flakes, white crystals, brown powders, etc.). It will also
smell mostly like dry yeast.
***
Joe writes:
>If you do the mass produced route - injected C02 carbonation. You need
>to get the beer real cold - (32F). Diffuse Co2 bubbles (as small as
>possible). You can have it carbonated in no time at all. Get the
>pressure/temp chart and your off. It is not CAMRA compliant, and it
>just does not taste as
>good (TO ME) refermented in the bottle beers. Sure is real duplicatable and
>easier
>tho...
You need not have it that cold. I have force-carbonated beer at 68F!
You simply look at the pressure/temp chart and use that pressure. At
68F it might be 45 psi of CO2. I also don't use a diffuser. I simply
shake the keg/PET bottle. I have learned to disconnect the supply hose
before shaking so beer doesn't go up towards the regulator, but other
than that, it's simple and cheap. Furthermore, CO2 is CO2 and it
dosen't matter whether it comes from sugar or from a tank. You might
get a miniscule amount of additional unfermentables from DME priming,
but the CO2 produced is exactly the same. The taste of force-carbonated
beer should *technically* be exactly the same as that from dextrose-primed
(and I'm a card-carrying CAMRA member, by the way!). The *mouthfeel*
of CO2-dispensed, fizzy, tighly-filtered beer is crap compared to unfiltered,
properly-conditioned, gravity- or handpump-dispensed beer, which is nectar.
*How* the CO2 got into solution (so long as the beer is still unfiltered
and served properly) should not have an effect.
Oh... after I force-carbonated that beer at 68F, I cooled it down to
serving temperatures and the carbonation was just as expected. Don't
try to dispense it at 68F and 45psi!!! Foam city!
Al.
Al Korzonas, Palos Hills, IL
korz@brewinfo.com
http://www.brewinfo.com/brewinfo/
------------------------------
Date: Tue, 9 Feb 1999 18:07:25 -0700
From: Armin Ulrich <ajulrich@telusplanet.net>
Subject: Of course hot water freezes faster
The main reason that hot water freezes faster is that the water molecules
in the hot water are in a higher energy state (buzzing about faster) and
that activity state has a flywheel effect as the water cools down, And that
activity facilitates evaporation which cools the water faster that the
water which starts out colder. The one caveat is that relative humidity
must not reach 100%(which leaves out most home size freezers). Don't
believe me try it out, put two containers outside one with hot and the
other with cold water in an see which one freezes first.
And for a extra low tech answer a few weeks back I saw video from Finland
where people threw boiling water into the air where it would freeze before
it hits the ground (Temp was -60C). Now why would anyone stand outside in
-60 (which is damn cold for those of you which have not experienced it) to
boil water when you could use cold water.
------------------------------
Date: Tue, 09 Feb 1999 18:41:53 -0800
From: Jeremy Bergsman <jeremybb@leland.Stanford.EDU>
Subject: Historic Porter/brown malt/Weyermann rauchmalt
Looking for advice on the following recipe. I am shooting for an historic
porter. I would like to use brown malt, but apparently what's available is
non-enzymatic (www.hoptech.com). Therefore I will be using the blend of dark
malts I have developed successfully in other porters, but in a lesser amount
based mostly on the estimated color contribution of the brown malt. In
addition to the brown malt character I want to have a smokey character like
older beers might well have had. Peat smoked malt seems wrong for this.
Checking the archives finds that while some will make a rauchbier with 95% of
this malt, others find this too smokey and I'm not going for Kaiserdom here.
25 and 35% were suggested but one should probably factor in the higher OG of
this beer compared to a rauchbier and stick to the lower side so I am
thinking around 25%. Here are my thoughts for 8 gallons:
10 lbs Hugh Baird Pale Ale (It's the UK malt I have)
5 lbs Weyermann beechwood smoked malt
3 lbs Hugh Baird brown malt (70L)
.5 lbs Caramunich (Dark crystal I have on hand)
.4 lbs Chocolate malt
4 oz Black malt
1 oz Roasted barley
Predicted OG on my system 1.075.
I will hop this to 57 IBUs, with 1.5 oz of EKG and .5 oz Bramling Cross for
flavor. Another possible flavor hop I have around is Willamette, but I like
the bramling cross.
Yeast will be WYeast 1335 (British II?) and a brettanomyces bruxellensis in
the secondary, which I will let go several months.
In addition to general comments I'd appreciate the following info:
-The Weyermann malt is enzymatic, right? Anyone have an approximate deg.
lintner? (If it's not bad I could increase the brown malt.)
-How about the color of the Weyermann?
-Anyone have any other source of brown malt?
- --
Jeremy Bergsman
jeremybb@leland.stanford.edu
http://www.stanford.edu/~jeremybb
------------------------------
Date: Tue, 09 Feb 1999 21:28:20 -0800
From: Jack Schmidling <arf@mc.net>
Subject: Momilies keep rolling in....
From: Alan McKay <amckay@magma.ca>
Subject: Is the Schmidling mill as good as a 6 roller?
The premise of Alan's question was so absurd that I was not going
to dignify it with a response but De Piro's knee jerk answer is
at least worth a few words.
First of all, NEVER and NOWHERE did I ever claim that any $100
two roller mill was "as good as" a $10,000+ 6 roller mill.
From: "George De Piro" <gdepiro@fcc.net>
"Alan asks about Jack's claim that his adjustable mill mimics a
6-roller mill:
" One final point on adjustable mills is worth putting on the
table. It is frequently suggested that the one sided
adjustability of the MM is a limitation when in fact, this
is actually the key to the so called "text book crush".
If you look at the oft published drawing of a six roller
mill, you will note that the roller spacings are about
.050", .030" and .012" from top to bottom. It just so
happens that, when an adjustable MM is set to near contact
at the adjustable end, one gets those same numbers at the
fixed end, center and adjustable end respectively. The end
rusult is that the random distrubution of grain across the
length of the rollers provides about the same grist
distribution as a six roll mill."
"The above is incorrect.....
I left my statement in tact because it is not obvious what
"is incorrect". The only thing I see even open to discusson
is the last sentence, which happens to be about as true as
anything Clinton has said in his life.
"About the same grist distribution" simply means that when you
weigh all the little piles that pass through the sieve test,
the weights are close enough not to argue about.
That is a fact and has been demonstrated by no less of an
authority than George Fix.
I do not dispute that by sifting out the husks in a multiroller
mill, one gets less husk fracture and this is why I would never
claim that it is "as good as" but for our purposes, the grist
distribution is/can be about the same. Whether that is of any
value to a homebrewer is fodder for another discussion.
"A mill with skewed rollers will not mimic this. In this
situation, some kernels will be unscathed while others will be
obliterated.....
This is patently untrue. There is no way a kernel can pass through
OUR mill unscathed. There is also no way they can be obliterated
if the close spacing is not less than the closest spacing on a
multiroller mill.
The fixed end is the same spacing as our "pre-adjusted" mill and if
grain passed through "unscathed" it would be useless. The other
end is user adjusted and has the same attendant risk of maladjustment
as a mill with both sides adjustable. It has the advantage that it
can not be so maladjusted as to make rubbish because the other end
assures a reasonable distribution of coarse "fines" and everything
in between across the rollers.
I do not know why this is so hard to understand but the proof of the
pudding is in the eating and no one has ever contended (until De Piro)
that the MM obliterates malt.
js
- --
Visit our WEB pages: http://user.mc.net/arf
ASTROPHOTO OF THE WEEK..... New Every Monday
------------------------------
Date: Tue, 09 Feb 1999 21:56:08 +0000
From: Jim Liddil <jliddil@azcc.arizona.edu>
Subject: "alcohol tolerance"
> Date: Sun, 7 Feb 1999 22:44:15 -0500
> From: "Tim Green" <timgreen@ix.netcom.com>
> Subject: Re: Maximum Alcohol
>
> One more note of maximum alcohol levels in fermented beverages, Wyeast
> sells a yeast they call Eau de Vie (water of life) #3347. They sell it for
> starting stuck fermentations and the production of single-malt beverages.
> They claim the alcohol tolerance of the yeast is 21%.
>
As I have said in the past alcohol tolerance is a porrly defined term. I
usggest you check the CRC article I have mention before. Chech the
archives. Essentially the research has shown little difference between
various yeast strains.
Jim
------------------------------
Date: Tue, 9 Feb 1999 23:45:00 -0600
From: "Rob Moline" <brewer@isunet.net>
Subject: The Jethro Gump Report...part 1.
The Jethro Gump Report
The recent discussion on ethanol levels in beer has prompted me to copy the
discussion portion of the Magnus, Casey, Ingledew paper on High Gravity
brewing for the HBD.....This is done purely for educational purposes only,
and I hope that it stimulates you to seek out the entire paper, and that it
satisfies many of the questions that it has for me....
Casey, Magnus, Ingledew..."High Gravity Brewing: Effects of Nutrition on
Yeast Composition, Fermentative Ability, and Alcohol Production."
"Regular production strains of brewers' yeasts can, with appropriate
nutritional supplementation, produce up to 16.2% (vol/vol) ethanol in the
batch fermentation of worts up to 31% dissolved solids. This occurs at 14C
without incremental feeding, with high yeast crop viability, and within
normal brewing time periods (i.e., less than 1 week.) The generalization,
then, that strains of saccharomyces used in brewing have only moderate
alchol tolerance (9) compaerd with strains used in distilleries (16) does
not hold true from a production viewpoint. Ehtanol concentrations of 16%
(vol/vol) are considered high, even in the distilling industry.
For brewing yeasts to produce these high levels of ethanol witkout an
excessively long or stuck fermentation, the wort must contain two types of
nutritional supplements; a nitrogen source (provided in this study by yeast
extract) and a combination of sterol (provided in this study by ergosterol,
the most prevalent sterol in Sachharomyces spp. [34]) with unsaturated fatty
acid (provided in this study by the oleic acid fraction of Tween 80). It is
important that both supplements be provided simultaneously: the fermentation
of high gravity worts then proceeds rapidly under both anaerobic (6) and
semianaerobic conditions (fig 1)
(Rob here.....fermentation conditions were maintained as anaerobic by
continual headspace purging with nitrogen @ a rate of 30 ml/min. ......"In
special circumstances, however, semi-anaerobic fermentations were carried
out where there was no nitrogen flushing, and foam plugs were used in the
sampling ports." )
These supplements act by increasing the amount of new yeast cell mass
synthesis over the levels seen in unsupplemented fermentations (Table 3.)
During wort fermentations, the rate of sugar conversion into ethanol is
considerably higher in growing yeast cells (up to 2.0 g'h per g of yeast)
than it is in stationery phase yeast cells (as low as 0.06 g/h per g of
yeasts) (21, 22) Clearly, it is not realistic to expect the rapid and
complete attenuation of high gravity worts by adding only brewing wort
syrups to normanl gravity wort bases, as is the current practice, (15). By
doing so, lipid and nitrogen deficiencies will limit the rate and final
level of ethanol production to levels much below the maximum possible, as
discussed below.
Lipids that are present in normal gravity worts in growth limiting
concentrations (7) must be synthesized by the yeasts in the first few hours
of fermentation while oxygen is still present (22). However, the decreasing
solubility of oxygen in worts with increasing original gravity (3) results
in high gravity worts which, if left unsupplemented, will certainly have
oxygen as a growth limiting nutrient. As demonstrated in this report, in
worts up to 31% disolved solids, oxygen deficiencies can be overcome by
either the addition of 24 ppm ergosterol with 0.24% (vol/vol) Tween 80 as a
source of oleic acid or by periods of oqygenation during the fermentation
(Figures 4 and 5.) On an industrial scale, the latter would likely be a more
economical option.
In low gravity worts, (10-12% dissolved solids) a minimum level of 150mg of
FAN per liter is required to permit rapid and complete attenuation (24).
Virtually all of this nitrogen is utilized within the first 24 hours of
fermentation,(31) at which point active yeast growth stops(19). In the
unsupplemented high gravity worts used in this study, levels of FAN ranged
from 165 - 250 mg/liter. This was not nearly enough to support the necessary
degree of of cell growth required to rapidly and completely ferment worts as
much as 3 times more concentrated than normal gravity worts. When yeast
extract was incorporated into fully supplemented worts, considerably more
FAN was utilized by the yeasts than was even available in total in the
unsupplemented worts (as much as 320 mg of FAN per liter.) The highest
levels of yeast extract required can be drastically reduced by the use of an
all malt base.(Fig 5)
Jethro Gump
------------------------------
Date: Tue, 9 Feb 1999 23:50:56 -0600
From: "Rob Moline" <brewer@isunet.net>
Subject: The Jethro Gump Report...part 2
The Jethro Gump Report..part 2
Casey, Magnus, Ingledew..."High Gravity Brewing: Effects of Nutrition on
Yeast Composition, Fermentative Ability, and Alcohol Production."
"It is apparent, therefore, that a frequently mentioned advantage of high
gravity brewing, namely, the increased yield of ethanol resulting from the
nonproportional increase in cell mass production with the increase in wort
gravity (30),is in fact an important disadvantage in worts above the current
commercial limit of 16-18% dissolved solids. Although the use of higher
levels of non-nitrogenous and cheaper adjuncts is possible in worts up to
this limit, above these levels, nutrient deficiencies will prematurely
terminate growth and therefore lead to significantly prolonged and in some
cases even stuck fermentations. In tthe past, such problems have been
attributed to the toxic influence of ethanol, (9, 17) when in fact growth
limiting levels of nitrogen and oxygen have not permitted sufficient new
yeast cell mass synthesis. Indeed, it appears that Saccharomyces
carlsbergenis cna be repeatedly repitched in 30% dissolved solids wort,
producing up to 14.2% (vol/vol) ethanol each time, without any increase in
in the time required for fermentation or decrease in the extent of
attenuation. In unsupplemented worts as low as 15.3% dissolved solids (with
40% adjunct), deteriorations in the rate of attenuation, the end gravity
reached, and the final ethanol concentration obtained have been observed,
even though the first generation gave normal and complete attenuation.(18)
The claim that ethanol concentrations as low as 8 to 9 % (vol/vol) are
sufficiently high to kill off a large enough portion of the yeast crop to
prevent its use for repitching (35) is therefore not accurate.
Supplementation was shown to have no influence on the fermentative
tolerance of the yeasts to ethanol(Table 2). this possibility was explored
because sake yeasts only produce the 20 to 23% (vol/vol) levels of ethanol
if the proteolipid component of Aspergillus orysae is present (17). In other
strains of Saccharomyces, exposure to 0.5 to 1.5 M ethanol causes an
increase in the proportion of monounsaturated fatty acyl residues in
cellular phospholipids (4). Also enhanced are tolerances to the effects of
ethanol on generation time, viability, and solute uptake when enrichment
with a C18:2 unsaturated fatty acid, rather than a C18:1 unsaturated fatty
acid was carried out (35). The early rise and then continued decline in
fermentative power values has been attributed to an increase in the cellular
levels of hexokinase activity by the buildup of intracellular ethanol levels
with time(27).
As the ethanol concentration of the Warburg assay increased up to 20%
(vol/vol), so did the degree of inhibiton of glycolytic activity. The
relationship between the activity remaining (relative to the 0% vol/vol
control) and the concentration of ethanol was found to be linear. However,
when the IF50 values of these plots were calculated, little difference
between the two sets of yeasts was seen at any point throughout the
fermentation. The values fluctuated within the range of 10.1 to 13.6%
(vol/vol) ethanol, with the highest IF50 values in fact being observed in
the yeasts from the unsupplemented fermentations. Improvements in the
supplemented fermentations on a per milligram of yeasts (dry weight) basis
were not due to supplementation increasing the tolerance of brewers' yeasts
fermentative ability to ethanol.
The enhanced death of yeasts in the high gravity wort fermentations with
increasing temperatures (Fig 3) was not an unexpected result. Ethanol and
temperature effects on yeasts are known to be closely related as (i) ethanol
becomes increasingly toxic to growth and viability at higher temperatures
(25, 26), (ii) ethanol decreases the optimum temperature of fermentation
(14), (iii) ethanol decreases the optimal and maximum temperatures for
growth (36), and (iv) higher temperatures of fermentation result in
decreased final ethanol concentrations in the mash (28).
The explanation for the increased inhibitory effects of ethanol at higher
temperatures has been attributed to increased accumulation of intracellular
ethanol at higher temperatures (26). Therefore, decreased fermentation times
arising from higher temperatures of fermentation are at the cost of poor
yeast crop viability, which is something that would eliminate their use in
brewing. In any case, the increased production of esters and higher alcohals
at higher temperatures would preclude the use of temperatures above 14 C for
the brewing industry (10). However, in the gasohol or distilling industries,
in which end yeast crop viability is not as critical, the combination of
nutritional supplemenation and temperatures up to 30C may be more practical.
Yeast crop cellular composition (especially glycogen and sterols) were
found to differ considerably between anaerobic and semi-anaerobic conditions
and to depend on the nutritional supplement used. The level of protein fell
consistently within the 40 to 50% range, but the amounts of cellular
glycogen and sterol fluctuated greatly. Glycogen levels were all less than
10% in yeasts under semi-anaerobic conditions, regardless of whether they
were unsupplemented or supplemented, whereas up to nearly 30% concentrations
were seen in the anaerobic fermentations (Table 1). However, the level in
the fully supplemented anaerobic yeasts, which gave the fastest feremntation
time (6), was 10.5%; this was the only crop under anaerobic conditions to
contain less than 26% glycogen.
The level of glycogen in brewers' yeasts is an important consideration, as
it is the sole source of metabolic energy for lipid synthesis and hexose
transport in the first few hours of fermentation (32). Because of this,
levels decline during the first 24 hours of fermentation, then rise and peak
at levels as high as 40% at the end of the growth phase, before gradually
declining during the stationary phase (19, 32). Pitching rates resulting in
the presence of 160 to 200 mg of glycogen per liter are suggested to ensure
enough glycogen for the synthesis of adequate lipid levels (32). Although
this might suggest a potential problem for the repitching of yeasts from the
supplemented fermentations, this was not found to be the case, as added
lipids can compensate for low glycogen levels Fig 3)."
Jethro Gump
------------------------------
Date: Wed, 10 Feb 1999 00:07:42 -0600
From: "Rob Moline" <brewer@isunet.net>
Subject: The Jethro Gump Report...part 3
The Jethro Gump Report...part 3
Casey, Magnus, Ingledew..."High Gravity Brewing: Effects of Nutrition on
Yeast Composition, Fermentative Ability, and Alcohol Production."
"Like glycogen, sterol levels varied between anaerobic and semianaerobic
conditions. Levels in the semi-anaerobically fermented yeasts ranged from
0.85 to 1.09%, depending on the type of supplementation (Table 1), comapared
with levels of only 0.27 to 0.56% in the anaerobically grown yeasts.
Clearly, oxygen is being introduced during the course of the semi-anaerobic
fermentations due to the higher levels of cellular sterols in these yeasts.
Brewers' yeasts normally have ca. 0.1% total sterols (dry weight) at
pitching but reach 1.0% or greater within the first several hours, utilizing
wort oxygen for de novo synthesis (22). The 1.0% level is a maximum ceiling
which is subsequently diluted down to a 0.1% lower limit by passage of
sterols to daughter cells(22).
Based on the results described above, it is clear that cellular sterol
levels alone are not the growth limiting factor in yeasts from
unsupplemented high gravity wort fermentations. In none of the yeast crops
from these fermentations was the lower limit of 0.1% sterols observed. In
fact, the lowest level reached was 0.48%, but this level was reached at day
6 of fermentation and remained unchanged up to the end of fermentation (day
12). It was not, therefore, the level of cellular sterols which caused the
cessation in new yeast cell mass production in the unsupplemented
fermentation, but other growth limiting nutrients. In the yeasts from
supplemented fermentations, the addition of the lipids in the supplement
elevated even further the levels of sterols away from the growth limiting
level of 0.1%.
It remains to be determined whether the 16-17% (vol/vol) levels of ethanol
reported here represent the true upper limit for brewers' yeasts. As sake
yeast can only produce the 20-23% (vol/vol) levels of ethanol by the
sequential addition of substrate over a period of weeks (17), it may well be
possible with the sequential addition of adjunct to produce beers of up to
20-23% (vol/vol) ethanol. Should this be possible, it would suggest the need
for a complete re-evaluation of the definition of alcohol tolerance in the
various species of Saccharomyces.
In addition, it is shown that the self imposed wort gravity limit of 16-18%
for high gravity brewing in industry should not be ascribed to sluggish and
stuck fermentations, yeast death, or intolerance to alcohol. It would appear
that brewers and alcohol manufacturers could easily consider production of
worts with higher graviites and enjoy larger economies of labor, capital,
and energy."
So, I hope that you have found this useful....I know that I did....I can
only apologize if i have mucked up the text from the original.....And while
I am not sure of some of the designations, I hope that the gist of the info
gets through.....
Again, this selected info from the article is reprinted only for
educational purposes...
Cheers!
Jethro Gump
Rob Moline
brewer@isunet.net
Lallemand Web Site Consultant
jethro@isunet.net
"The More I Know About Yeast, The More I Realize I Need To Know More About
Yeast!"
------------------------------
Date: Wed, 10 Feb 1999 05:41:45 -0500
From: Rod Prather <rodpr@iquest.net>
Subject: Alcohol content and fortification
I believe the addition of more must is done in Flor sherrys. I am not sure
of the process. Once again I have unsupported information, Jeff. What I
rememeber what that the Flor was continuously fed while wine was taken off
of the vat. The reason was that a flor, or hard yeast cap, only forms in
certain situations and is difficult to attain. Once attained, the cap would
keep so the vintner wanted to take full advantage of it, thus the feeding
process.
It is my personal observation that hearty, alcohol tolerant sherry yeasts
were borne of this process. Note that sherry yeast frequently have
alcohol tolerances in the 17 percent ranges and are noted for their alcohol
tolerance.
Still you are right, both sherry and port is fortified, usually with
brandy. The increased alcohol content halts bottle aging and causes the
wine to keep for long periods of time, thus 100 year old ports and sherrys.
Secondly, the fortification also has an asthetic value of modifying the
flavor slightly for the better.
It is my understanding that Sake, on the other hand, can attain alcohol
contents in the 20% range simply by yeast accomodation. Poorer quality
sakes have also been fortified. These were the ones that were typically
drank warm. Japanese and American sake brewers are trying to bring the
higer quality, unfortified sake into vogue in the US. These are typically
more flavorful, fuller bodied and drank cold.
Jeff Renner wrote.
> still more clarification. I've just read the entry on Sherry in Alexis
> Lichine's _New Encyclopedia of Wines and Spirits_ (1974 ed., OK, not so
> new, but neither am I) to confirm my recollection that Sherry is fortified,
> and find that it is except for some for domestic consumption. I can't find
> anything about the slow addition of more sugars, but that doesn't mean it
> isn't done.
>
------------------------------
Date: Wed, 10 Feb 1999 06:37:41 -0500
From: "S. Wesley" <WESLEY@MAINE.MAINE.EDU>
Subject: RE: Rod P.'s "Math challenge"
Rod Prather asks for a mathematical solution to the following
question:
If a coil of length L is immersed in a resivoir of temp Tr so that
fluid flows into the coil at temp Tin what will be the output
temperature Tout.
An upper limit on Tout can be found from:
Tout </= Tr - (Tr-Tin)e^(-sL)
Where s = kp/((rho)AcWv)
Here k = thermal conductivity p= the circumfrence of the tube
(rho)= density of fluid A =cross sectional area of pipe
W= thickness of wall v = velocity of fluid
c= specific heat of fluid
Note that vA is just the flux of water through the tube (volume rate
of flow.)
I say this gives an upper limit because the model used to derive this
expression depends on the questionable assumption that heat absorbed
near the tube is instantly transmitted to the element of water nearby
(flow is highly turbulent) and there is also good flow around the
outside of the coil. Years of experience putzing around and
experimenting with immersion chillers lead me to belive that the
circulation created by heating the resivoir will not produce adequate
flow around the coil to maximize heat transfer. (Some sort of
vigorous stirring mechanism is required.)
It is comforting to note that this model agrees with expectations in
the limiting cases of L = 0 and L= infinity. For L=0 Tout = Tin and
for L= infinity Tout = Tr.
------------------------------
Date: Wed, 10 Feb 1999 07:15:05 -0500
From: Mark Tumarkin <mark_t@ix.netcom.com>
Subject: re: bottler thingies
Bill Graham writes:
I've spent a fair chunk of change on my brewing setup, but have
spent nothing on bottling (except $5 for the old Eveready bottle capper
at
a garage sale.). I would like to graduate beyond squirting beer into a
bottle from a vinyl hose, squeezing it off with thumb and finger when
moving to the next. Can anyone recommend a bottle filler? I fill many
different sizes, so it would have to account for that. I'm not kegging,
so
counterpressure doohickies are out.
Many people seem to dislike bottling, thinking it is a hassle. I am not
one of them. I don't mind bottling at all (although I plan on getting
into kegging a bit soon as well). I think part of it is having good
equipment. If you have spent "a chunk of change" on your other
equipment, you probably won't mind spending a little bit more on the
bottling setup - hey, toys are fun!.
I use a phil's philler, and am quite happy with it. I would suggest
getting a few other items. First, a jet-washer. Second, a bottle tree,
and lastly a bench-type capper. I am not familiar with your Eveready -
it may be a bench capper. I have found that if you get into the habit of
rinsing your bottles right after you pour them (or at least as soon as
possible), maintaining good sanitation by blasting the bottles with the
jet-washer, putting them into the bottling bucket filled with iodophor,
and then draining on the bottling tree is simple. It does seem a little
like work, but just think of it as Zen and the Art of Bottle
Maintainence.
Mark Tumarkin
Gainesville, FL
way south of Jeff and Al
------------------------------
Date: Wed, 10 Feb 1999 05:41:47 -0700
From: Ken Schwartz <kenbob@elp.rr.com>
Subject: Dispensing from kegs without a CO2 bottle / Y2KBW
Running a keg from non-tank CO2 sources has been discussed in length,
but if you're looking for an easy solution for dispensing a keg within a
few days (like at a party), check out my web page and find the article
on "Keg Hand Pump". Easy to rig up and cheap. Since it dispenses ith
air, staling of the beer in time is a concern, so plan to consume the
whole keg soon (get some help).
- -----
Lotsa talk about Millenium BW's. Cap'n Marc wants to make one using
Danstar Nottingham. I brewed my "Ninety-Nine Barleywine" in November
1997 (before "Y2K" really entered the vernacular) using that same
yeast. I would suggest using at least two packs. This dry yeast can
usually be had for $1 or less so it's not like you're straining the
yeast budget compared with liquid cultures. Pitch large and oxygenate
well. BTW my BW went from 1.092 to 1.017 in about a week.
- --
*****
Ken Schwartz
El Paso, TX
Brewing Web Page: http://home.elp.rr.com/brewbeer
E-mail: kenbob@elp.rr.com
------------------------------
Date: Wed, 10 Feb 1999 07:42:06 -0500 (EST)
From: LEAVITDG@SPLAVA.CC.PLATTSBURGH.EDU
Subject: dry hop with Fuggles ?
Date sent: 10-FEB-1999 07:34:25
I am building up a stock of homebrews for a wedding reception that we are
having at our house in June. Knowing that lots of folks like lighter brews
I brewed up and Irish Ale (so named primarily because of the yeast, Wyeast
# 1084 [4lb Baird's Vienna malt, 8lb Maris Otter 2 row, I cup crystal, 1 oz
Hallertau @ start, 1/2 oz @ 30, 1/2 oz @ 15]), mash sched was (partial boil
): 147 F for 40 min, 155 F for 40, OG=1.070, FG=1.014)...Now here is the
question: When I tasted it, going into the secondary, it tasted a bit mild
(as planned) but I wanted to zip it up a bit, so I dry hopped with 1/2 oz
Fuggles...and upon bottling this appears to not have done too much...still
pretty mild (malt and hops). Should I have added more, or are these the
wrong hops for dry hopping?
...Darrell
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ _/
_/Darrell Leavitt _/
_/INternet: leavitdg@splava.cc.plattsburgh.edu _/
_/AMpr.net: n2ixl@amgate.net.plattsburgh.edu _/
_/AX25 : n2ixl @ kd2aj.#nny.ny.usa _/
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
------------------------------
Date: Wed, 10 Feb 1999 08:19:09 -0500 (EST)
From: LEAVITDG@SPLAVA.CC.PLATTSBURGH.EDU
Subject: Efficiency question: Am I getting enough out of the malt?
Date sent: 10-FEB-1999 08:05:56
I have been trying to do all-grain, but withoug a proper sized kettle.
Mine is just 20 quarts, so I need to add H2o to get 5 gallons...but I
wondered if I could get some feedback from the group as to my procedure...
given the equipment limitations...?
Here is my typical mash: 3 gal H2o into kettle, take it up to 147 F (or
whatever, based upon the malt)...add 10-12 lb malt (sometimes some flaked
barley)... this just about fills the pot...heat to temp and let sit for 30-
40 minutes, then heat again up to 155 F (or so) [note: I have tried to draw
off several quarts and boil them <deconction?>, then add back at times],
and let sit at this second step for 40 minutes...
then mash out at 168-170...then I place the grains into a zapap sort of
thingy that I have put together, I recirculate until it seems to be running
pretty clear...(reheating at times with microwave so as to maintain temp),
then I start to draw a pint off at a time, placing it tinto the brewpot,
while replacing that pint with a pint of sparge water (trying to watch pH).
..I keep doing this until I can get no more into my wimpy 20 quart kettle..
.sometimes I have a gallon or so to add as the wort boils down.
I have generally found that when it starts running clear I find a gravity
of about 1.07 , sometimes as high as 1.09... then near the end of the
sparging the gravity is usually around 1.02 or 1.03
The OG, once I have chilled and added some H2o is generally around 1.07 ,
sometimes nearer to 1.05 if I used a few pounds less grain. My question is:
Does this seem ok for the equipment that I am using, or should I expect
more?
I know that there are a lot of variables...so I appreciate any thoughts.
...Darrell
<Plattsburgh,NY>
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ _/
_/Darrell Leavitt _/
_/INternet: leavitdg@splava.cc.plattsburgh.edu _/
_/AMpr.net: n2ixl@amgate.net.plattsburgh.edu _/
_/AX25 : n2ixl @ kd2aj.#nny.ny.usa _/
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
------------------------------
Date: Wed, 10 Feb 1999 05:24:59 -0800 (PST)
From: Matthew Comstock <mccomstock@yahoo.com>
Subject: Yeast Autolysis/Yeast Library?
Teach a guy how to homebrew, and he will worry himself to death.
Jeez. I've been following this thread about yeast autolysis and
oxidation with interest(only noticed what I thought was autolysis once
in a raspberry mead after about a month in the bottle. It went away
after about two months = Lalvin K1V-1116, made a fine mead in the
end). Today Fred L. Johnson asked the question that pops up in the
archives once and a while - and I've asked recently -
"How is storage on the cake of yeast in the primary any different than
storage on the cake in the secondary or in the bottle? And if yeast
autolysis is such a problem, how can one produce a decent
bottle-conditioned beer, such as a barleywine or any other big beer,
that is supposed to REQUIRE some aging to produce its characteristic
flavors?"
I've seen someone, Pat Babcock?, answer this by saying its not the
yeast that is a problem in the primary, maybe leading to off-flavors,
but the trub and break material.
In the past few days, and today, people have commented that autolysis
problems are yeast specific. Can we develop a library of this and
other information about specific yeast strains. This info could more
useful than the manufacturer's comments. For example, I wonder what
yeast John Varady is using:
"I often leave my beer on the yeast for 3-6 weeks before bottling,
skipping a secondary vessel entirely. I find that I get clean, clear
beer that
carbonates within 2 weeks and has very little bottle sediment. I have
never noticed any "meaty" or "rubbery" aromas from this practice and
would certainly discontinue it if I did."
Maybe we already have a library of 'real' info about yeast strains
available. It seems important to categorize our autolysis comments,
and other useful comments, by yeast strain, negative or not.
Otherwise we will have a stand-off between people like John Varady
saying he's never had a problem, and others saying that a week on the
primary yeast cake is a sure recipe for disaster, when they may be
using very different yeast strains.
OK, here's a lame start. I've used Munton's dry ale yeast, Edme dry
ale yeast, Wyeast 1056, and Wyeast 1028, and used *only* a primary in
all but one case. All batches sat at least 10 to 11 days in the
primary, and most for 14 days. I repitched onto the primary yeast
cake twice, once using Wyeast 1056 and once with Wyeast 1028. None of
these beers had a rubbery or goofy off-taste. Only the beer made with
Munton's dry ale yeast tasted different than I expected. It was kind
of sweet, estery? - I decided it fermented too warm, about 74 F. The
7.5 EtOH stout I made with Wyeast 1056 was real thick, FG = 1.022, but
good. I thought it had a not-unpleasant yeast flavor. Liquid bread,
indeed.
If there isn't a library already, let decide on a format for this
info. Sure we could search the archives for our yeast of interest,
but that can be a long exercise.
Laters
Matt in Cincinnati, OH
_________________________________________________________
DO YOU YAHOO!?
Get your free @yahoo.com address at http://mail.yahoo.com
------------------------------
Date: Wed, 10 Feb 1999 08:31:21 -0500
From: PAUL W HAAF JR <haafbrau1@juno.com>
Subject: Making candi sugar / beer stock
Can someone send me a recipe for making candi sugar?
My attempts at searhing the archives proved my web
searching deficiency. TIA.
As far as keeping a beer based stock in the fridge longer
than a normal stock, isn't most of the alcohol cooked out
when you reduced from one gallon to one quart?
Paul Haaf
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------------------------------
End of HOMEBREW Digest #2952, 02/12/99
*************************************
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