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HOMEBREW Digest #2790
HOMEBREW Digest #2790 Fri 07 August 1998
FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
Digest Janitor: janitor@hbd.org
Many thanks to the Observer & Eccentric Newspapers of
Livonia, Michigan for sponsoring the Homebrew Digest.
URL: http://www.oeonline.com
Contents:
Dry hopping (Craig & Denise Jensen)
Stuff (Jim Liddil)
Acidifying Sparge Water (Tony Barnsley)
re Yeast Concentration Prior to Fermentation Stage ("Steve Alexander")
Pitching rates ("Steve Alexander")
Patron Saint of Brewing/Beer??? (John Baxter Biggins)
Keg Line Pressure Drop (Bob.Sutton)
Holes in yer fridge (Nathan Kanous)
Re: pH data (Rod Schaffter)
Re: sparge water acidification (Herbert Bresler)
Pharr Out Acidity, Stuck wine, reducung sugars ("David R. Burley")
Gypsum & pH Adjustment (Ken Schwartz)
RE: Clinit*st (LaBorde, Ronald)
Commercial Starters (Charley Burns)
RE: coiled hose (John Wilkinson)
Re:Patron Saint of Brewing/Beer??? (Some Guy)
re: Holes in the fridge ("Ludwig's")
Harvesting Homegrown Hops ("Joel Plutchak")
Microwave / Yeast Harvest ?/ Clubs ? (cdknotts)
Saturday's Brew ("Kris Jacobs")
Boiler Sight Gauge Question/Manifold vs. False Bottom (bob_poirier)
Peter on repitching; underpitching; recipe conversion; Infected Primary (Samuel Mize)
Refractometer (William Graham)
There will be a Sunday Digest this week...
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----------------------------------------------------------------------
Date: Tue, 04 Aug 1998 21:38:54 -0700
From: Craig & Denise Jensen <fourtrax@gte.net>
Subject: Dry hopping
As a first time poster, I'll see how this works...
I wanted to send a quick note for those who are looking at different
methods of dry-hopping, specifically in a corny keg. I am enjoying good
success using the following method:
I drilled a small hole about 1/4" from the end of the dip tube. After
inserting the dip tube, I used nylon fishing line to thread through the
hole, then tied it tightly around my hop bag filled with whole leaf hops
(the bag being boiled for 15 minutes). I left only about 3" of 4" of
line between the tube and the hop bag, to ensure that the hops remained
under the surface of the beer and in as much contact as possible.
It is now 2 weeks since kegging, and the hop flavor is increasing by
the day. I have only had one or two specks of hop material make it to
my glass so far, although results at the end of the keg remain to be
seen. Hope this helps someone!
------------------------------
Date: Tue, 04 Aug 1998 21:26:50 -0700
From: Jim Liddil <jliddil@azcc.arizona.edu>
Subject: Stuff
Dave burley wrote:
>Forced fermentations may offer a clue to when the fermentation will be
>furnished, but are subject to indeterminate errors. Remember that
>this same forced fermentation method is also used to determine the
>stability of the beer, as a check for unwanted bacterial fermentation.
>Bacteria function better at elevated temperatures, so likely any even
>slightly infected beer will give an FG dependent on the bacterial content
>as contrasted to a fermentation that was carried out at cooler
>temperatures.
I have to disagree with this and wonder if by chance you did not read the
followup post I wrote after George DePiro's on force fermentation. Geroge
worte that ne can use a package of yeast to ferment out 100 ml of wort or
so in a day or two to get a true final gravity. I followed up wiht
description of the way Siebels does the test. By overpitching one is
producing an evironemtn that is inhospitable to fast grwoing organisms.
Any organism that will grow and cause super attenuation are very slow
growers. So if one does the 4-5 hour technique the chances of other
microorganism affecting the gravity are essentially nil. Have you every
tried growing wild yeast or lactic acid bacteria on purpose and seen how
slow they grow? I have.
>The whole point of this hobby for most
>homebrewers is to make all kinds of beers with various
>( intentional or accidental) mash temperature profiles and yeast that
>behave differently. As a result, we almost never know what the final
>FG will be, since we have no experience. Given this, how do we know
>what the expected FG is supposed to be?
>
>Actually you don't care what the FG is supposed to be, but as AlK
>points out to know "Is the beer done?" This is another way of saying
>"Are there any more fermentable sugars in the beer?"
>
No Dave YOU don't care what the final gravity is. Don't go telling us all
what we care about! By doing a forced ferment test, in the proper manner,
one can find out what the final gravity is going to be.
>However, I believe
>they are a cumbersome, 1800s, time consuming and full
>of error method of determining a fermentation endpoint. Worst of all
>these errors are indeterminate and vary from batch to batch.
That's why Miller and AB still do them even though the have Scaba and Paar
beer analyzers. All you''re blowing smoke about how inaccurate and
imprecise a hydrometer is, is baloney. One can learn to use one correctly
and degas the beer etc. In the forced test the beer is essentially
degassed from the vigorous agitation or stirring used. So all chemist
should abandone grad. cylinders and pipets because there is no way in hell
one can learn to read a meniscus properly? Oh please.
Mort wrote:
Technically, Steve is correct in saying that fermentation rate is
^^^^^^^^^^^^
>dependent on viable biomass, and not growth. I have some recent data >from
my own experiments that illustrates this point perfectly:
>
>
Massive overpitching data deleted
>This data shows clearly that fermentation rate is governed by biomass, not
>yeast growth.
>
>
Yea, clearly. But this is purely an acedemic experiment. It would make no
sense to grow and pitch this much yeast on a commercial scale and most
homebrewers don't have the resources to do this kind of scale up for 5
gallons. It's easy to do with a 300 ml at Hariot Watt. and we have to ask
can this make good beer on a repeated basis? Granted you made your point
but few are going to make beer using this method. The satement Lord Peter
made is correct for the majority of commercial and homebrewers
Lord Peter wrote:
>So, my thinking here is:
>1) Oxygen is the primary limiting factor in yeast growth.
In a fermentation where the yeast have come from a previous fermentation
and ahve low sterol levels to start with. And oxygen is only a limiting
factor in normal fermentations where it is introduced once at the beginning
of the ferment.
>2) The yeast will not begin the logarithmic growth phase until they have
>proper amounts of aforementioned ergosterol.
And the have had a chance to adjust all their other metabloic acitivities etc.
>3) The lag time is the period between pitching and the logarithmic growth
>phase.
>4) Therefore, O2 in sufficient quantities will remove this limiting factor
>of growth. The yeast did not have to wait around to get the proper
>components they need to begin the growth phase.
NO. thsi only applies to yeast that are 95+% viable and are already
adapted. the lag phase is a period of adaption. Oxygen will only aid in
membrane formation. it does not help the cells adapt to temperature, nor
does it help them get their metabolic acitivities going.
>5) Does this not mean that not only will the fermentation proceed at a
>faster rate because of increase growth, but also that it will begin the
>fermentation sooner because it had the proper tools to begin with?
>
Lag phase is governed by the temperature of the wort, the state of the
yeast, the flocullating ability of they yeast (have they been acid washed)
and what kind of wort are they being put into (chemcial make up). The
yeast will suck up all the oxygen and make sterols, but this will not
cahnge the time spend in lag phase. they still have to adpat to the new
environment regardless of oxygen level.
Jim
------------------------------
Date: Wed, 5 Aug 1998 10:24:58 +0100
From: Tony Barnsley <Tony.Barnsley@riva-group.com>
Subject: Acidifying Sparge Water
Jeff Wrote, about problems using Gypsum to Acidify his sparge water.
Adding gypsum to the water will RAISE the pH of the water. It LOWERS the
pH of the mash because it binds with other minerals releasing free
phosphate into the mash and thus lowers the pH.
For those people that feel they MUST lower the pH of their sparge water.
then a few drops of Phosphoric / Lactic Acid will do the job very
effectively (In my water, as always YMMV). Of course you can also use
Citric, Malic or Tartaric acids at a pinch.
Be aware however that over acidification of the wort may result in poor
or no Hot break formation (Thanks to AlK for that one. By the way Al
Around what pH does this start to become apparent?)
Wassail !
Tony, M.i.B (Mashing in Blackpool, Lancashire, UK)
------------------------------
Date: Wed, 5 Aug 1998 05:58:04 -0400
From: "Steve Alexander" <steve-alexander@worldnet.att.net>
Subject: re Yeast Concentration Prior to Fermentation Stage
Peter Gilbreath writes ...
>Lyn Kruger, in notes from Siebel Short Course, 1997:
>"Governing principal in fermentation:
>The rate of fermentation will depend on the rate and extent of yeast
>growth."
I'm somehow starting to associate this name with unsupportable nonsense.
Mort answered this issue tho'.
>>[...]that bears repeating. Lipids are any material that can be
>>dissolved in non-polar solvents, [...] a pretty generic term and[...]
>Again, Siebel Course 97:
>"Lipid is a generic term given to a group of alcohol, ether, and fat
>solvents."
McMurry, 'Organic Chemistry', Brooks Cole Publ. 4th edition, pp 1099, "Lipids
are the naturally occurring organic molecules isolated from cells by extraction
with non-polar organic solvents".
Mathews&van Holde, 'Biochemistry', Benjamin/Cummins Publ. 2nd edition,pp 12,
"Lipids are a chemically diverse group of compounds that are classified
together because of their apolar structure which gives them very low solubility
in the aqueous environment of the cell".
These would not be alcohol or ether solvents, Fats are lipids, but the Seibel
definition doesn't really say that does it ? Please cross out the Seibel
definition
and replace it with something correct.
[...]
>"Once sufficient oxygen has been adsorbed from the wort to build up the
>ergosterol concentration, and the sugars and amino acids are utilized by the
>yeast, the cells begin to multiply. Multiplication continues in geometric
>progression, called the logarithmic phase of growth, until the material in
>shortest supply is used up, growth then slows down and finally the number of
>yeast cells remains constant."
This growth phase seems to be called the "EXPONENTIAL" not "LOGARITHMIC"
phase by everyone else. It should also have been noted that the "material"
used up
must be a critical not a supportive(synthesizable) nutrient in order to limit
growth.
>"Under normal brewery conditions the factor that usually limits yeast growth
>is the amount of oxygen available in the wort."
Well sterols and UFAs really, which are dependent for synthesis on oxygen, but
can also be absorbed from wort..
>"When the rate , on a per cell or per gram basis, at which yeast uses the
>sugar in wort when growth has ceased is measured, it is found to be very
>slow. In contrast, sugar is utilized relatively rapidly when growth is
>occurring."
There are several reasons for a rate change - not the least of which is that
the simple mono-sugars are used up and so a typical beer is dependent on
metabolizing bigger (slower to catabolize?) sugars during the stationary phase.
It is true that growth requires a pretty fair amount of carbs for energy. The
few graphs I have do not show this major rate decline in CO2 (a proxy for
fermentation) during the early & mid stationary phase. I have a very nice
paper by Gee and Ramirez from JIB from the 1980's which shows a near linear
consumption of the individual sugars once they started to be consumed until
their individual levels drop too low. I would assert that under 'normal'
brewing conditions that the fermentation rate starts to drop sometime after,
and not coincident with, the end of exponential growth.
>So, my thinking here is:
>1) Oxygen is the primary limiting factor in yeast growth.
Sterol and (maybe) UFAs ar the limiting factor, whether synthesized of absorbed
from wort lipids. Also remember that the pitched yeast ideally have enough
sterol to divide ~3 times w/o other sterol synthesis or absorption - so in a
sense the pitched yeast state is a limiting factor to growth too.
>2) The yeast will not begin the logarithmic growth phase until they have
>proper amounts of aforementioned ergosterol.
I strongly suspect this is nearly correct, *but* what you are stating above is
a critical fact of yeast metabolism if true - and so I will need a reference to
really swallow the story that yeast actually WAIT, delaying division until a
"proper" lipid level is developed. My guess based on competition and so
evolutionary pressure is that yeast *may* delay reproduction in the presence of
sufficient O2, and even more doubtful, that yeast *may* delay reproduction
until wort sterols are consumed. Either/both of these are different from what
you state - and different consequences accrue. I feel that this theory of a
delay is highly speculative. It is fully possible that yeast split as soon as
they can grab enough sterol(and many other necessities). Perhaps you have a
source for this delayed division metabolism - I haven't seen one - but
would love to.
>3) The lag time is the period between pitching and the logarithmic growth
>phase.
Many books, several books on bioreactors, M&BS too, include a transitional
phases too. This is just a matter of definition - so OK.
>4) Therefore, O2 in sufficient quantities will remove this limiting factor
>of growth
That's easy - YES, I agree.
>The yeast did not have to wait around to get the proper
>components they need to begin the growth phase.
Doesn't follow, because of crabtree effect in fresh wort (~1% glucose) I'm not
entirely convinced that yeast even *CAN* absorb O2 initially. I have
doubts about whether they really "wait", tho I think it's possible
>5) Does this not mean that not only will the fermentation proceed at a
>faster rate because of increase growth, but also that it will begin the
>fermentation sooner because it had the proper tools to begin with?
Not at all - you are ignoring the fermentation that would be occurring due to
the original pitched yeast mass regardless of growth.
Perhaps the problem is this - There are two things that you might mean my
"fermentation". 1/The amount of fermentation that takes place in a given wort.
2/ the amount of fermentation accomplished by a given group of yeast and their
progeny. Your Seibel definition seems to mean 2/. While I and M&BS, pp 645 or
G.Fix AoBT pp 79-81 clearly mean 1/. Many texts state that pitching additional
yeast leads to shorter(faster) fermentations. This has no meaning relative to
2/.
>I have not seen any reports or studies that directly rule out O2 sat as a
>factor in lag phase length, nor have I seen any that directly support this.
>What I do see is a lot of evidence that points me to believe that O2 sats do
>indeed influence the length of lag. Please, someone quote a reliable source
>to dispel my thoughts, and / or point to the holes in my logic. Timo?
What I see are a lot of references that relate lag to delays in producing
permeability enzymes, accounting for shock excretion, osmotic pressure changes
and metabolic changes to undergo the crabtree effect due to the high (~1%)
glucose levels in AG-Wort. There are a lot of references in M&BS, vol2 - but
frankly any decent book that covers saccharomyces metabolism should have this.
I'd check, 'The Yeasts', by Cambridge press from memory).
Steve Alexander
------------------------------
Date: Wed, 5 Aug 1998 05:46:39 -0400
From: "Steve Alexander" <steve-alexander@worldnet.att.net>
Subject: Pitching rates
Jim Liddel writes about my comments on pitching ...
>> The recommended yeast growth rates are that ale yeast should grow by ~8-10X
>> and Lager yeast by 4-5X. This would argue in favor starters for 5gal (20L)
>According to Lyn Kruger during class and over a few glasses of Guiness the
>most
>growth you want for ales and lager, regardless of scale (5 gallons or 900
>barrels) is a ~3X. A yeast cell in ideal condition hits the fermenter with 1%
Are you sure this isn't 3 divisions (8X) Jim ? 3X may make sense in terms of
desired sterol levels, but is clearly out of whack with commercial practice as
I read about it the Tech Journals from either side of the Atlantic. As I read
more of these extreme statements from Seibel it makes me doubt that they know
what they are talking about. Can Lyn Kruger point to a Journal article to
support this weird point of view ?
>Is autolysis rare in homebrewing? Without doing viability staining this
>is purely conjecture in my view.
Yes, based on my experience.
Steve
------------------------------
Date: Sat, 05 Sep 1998 08:12:01 -0700
From: John Baxter Biggins <jbbiggin@mail.med.cornell.edu>
Subject: Patron Saint of Brewing/Beer???
Anyone out there know who the patron saint of Brewing or Beer is (if
there is one)???
John Biggins
Cornell University Grad School of Medical Sciences
Memorial Sloan-Kettering Cancer Center
------------------------------
Date: Wed, 5 Aug 1998 08:28:15 -0400
From: Bob.Sutton@fluordaniel.com
Subject: Keg Line Pressure Drop
Al, you wrote....
|Laurel writes:
|>In answer to Mark Swenson's question about dispensing from a keg at
|>relatively high pressure - you're right to use a longer dispense line,
|>but you might also try coiling it up several times (say, a 5-6" diameter
|>coil or as small as you can make it without kinking the tubing) to give
|>more back pressure.
|Are you sure about this? I don't see how coiling would increase back
|pressure... the fact is that flow is what causes the pressure drop.
|Is there an "inductor-like" effect (like coiling a wire)? No... there
|can't be... can there? An inductor works because a magnetic field is
|generated.
You need a geeky engineer to answer this one...
In non-laminar flow regimes, fittings such as elbows (including long radius
turns) generate more frictional resistance than simply the linear path length of
the fitting (if the Reynold's Number is less than 2100, the effect decreases.).
In fact a simplified means to predict pressure drop in systems applies an
"equivalent length" factor to each fitting to represent the linear equivalent of
resistance.
So by coiling the tubing, Laurel is creating a series of long radius ells, which
will offer frictional resistance greater than leaving the tubing in a linear
configuration.
Here's an oversimplified illustration...
Let's assume we have a long radius ell with an inner diameter of 0.25 inch
(D=0.25), and let's set the bend radius (to the tubing centerline) at five
inches (R=5; no ASCII art - use your mind). The linear length of a 360 degree
loop can be computed by calculating the centerline circumference as 2*5*pi, or
~34.2 inches. Cameron's hydraulic data states that the length/diameter (L/D)
value for a long radius ell (R/D=20) is 50.
Since we have a single loop, the equivalent length of our example is:
50*4*0.25 = 50 inches, where
4 = the number of 90 degree ells to form a loop
0.25 = the ID of our example system.
So in fact we've added nearly sixty percent to the linear hydraulic resistance
(not backpressure) by forming a loop with a 10 inch diameter.
Bob
Fruit Fly Brewhaus
Yesterdays' Technology Today
------------------------------
Date: Wed, 05 Aug 1998 08:01:46 -0500
From: Nathan Kanous <nlkanous@pharmacy.wisc.edu>
Subject: Holes in yer fridge
Robert Johnson asks about holes in his fridge. I've done two fridges so
far (one died of old age). For both, I made holes in the front of the door
for taps. I also ran my CO2 line in through the edge of the door, on the
hinged side. It can get a little tight if you need to open the door all
the way, but works very well. No problems. The only modification that I
included was to put a rubber o-ring (just like the one in a "fermentation
bucket" where the airlock goes) around the CO2 line to protect it from the
metal. The o-ring may not provide a lot of protection, but it makes me
feel like I did something to protect it. YMMV
nathan
Nathan L. Kanous II, Pharm.D., BCPS
Clinical Assistant Professor
School of Pharmacy
University of Wisconsin - Madison
Office Phone (608) 263-1779
Pager (608) 265-7000 #2246 (digital)
------------------------------
Date: Wed, 05 Aug 1998 09:13:16 -0400
From: Rod Schaffter <schaffte@delanet.com>
Subject: Re: pH data
Fred Johnson inquires:
> What is the convention among the biochemists of the temperature at
which
> one specifies the pH of the enzyme reaction being measure? And is
this
> the convention used by whomever determined the pH optima of the
enzymes we
> are dealing with? I really don't care what Miller or anybody else's
standard
> practice is. I want to know what the biochemist did when he studied
the enzyme!
>
> It seems that unless one has the answer to this last question, we're
only
> guessing as to the appropriate temperature at which pH should be
measured
> in the brewhouse.
I can't speak for Biochemists, but Analytical Chemists measure
pH (and most other electrochemical measurements) at 25 C. The reason
for this is that a pH meter actually measures a voltage that is
dependent the hydrogen ion concentration. (yeah, I know that it it is
really related to hydrogen ion _activity_, but I can brew a batch in
the time it would take me to explain pH in terms of activities well!)
Hydrogen ion concentration is dependent on the dissociation constants
(tendency to
break up into separate ions) of all of the acids and bases in the
solution. Dissociation reactions of weak acids and bases are
temperature dependent, and also dependent on the concentrations of all
of the other ions in solution.
In addition, the dissociation constant of pure water is highly
temperature dependent. According to my trusty CRC Handbook, The
(Calculated) pH of pure water would be 7.47 at 0 C, 7.00 at 25 C
(actually 6.99825), and 6.51 at 60 C. Also any measurement is
dependent on the standards used, which are the buffers used to
calibrate the meter. These are calibrated at 25 C, and their actual
pH will usually exhibit a lesser degree of temperature dependence,
due to the added twist of the temperature dependence of the
dissociation constants of the buffer acid and base pairs, but the pH
may go up or down with temperature, depending on the specific buffer.
This behavior is relevant not only from a calibration standpoint, but
because wort contains both weak acids and bases (e.g. polyphenols and
proteins) and thus is also a buffer, and will exhibit similar
temperature dependence, that is, unpredictable. (I'm sure that someone
has done some experiments in this area, so speak up!). The indicators
used in pH papers also exhibit temperature dependent behavior, as the
color change is due to changes in ionization of the indicator dye
molecule.
ATC on a pH meter can compensate for small differences in temperature,
but in my career, I have had the luxury of taking my samples to the lab
and measuring them at 25 C. In Situ measurements of pH must account
for differences in temperature, or all be run at a stated temperature.
The question to be asked is, "is all of this jargon relevant to
brewing?" From my limited experience in mashing, I must give an
unqualified "Maybe"
;-). I would say that cooling the sample to room temperature should
give quite satisfactory results, and investing in a 25 C temperature
controlled bath would probably not improve your brew. (although if
anyone has done this, please add your $ 0.02!) Keep in mind that folks
brewed at least drinkable beer for thousands of years, and good beer
for hundreds of years, before the discovery of ionization chemistry (or
thermometers!). The product of controlling these parameters is a more
consistent brew.
What we need to keep in mind as brewers (and as citizens) is
that physical and chemical measurements are usually dependent on the
measurement conditions, and unless there is a convention as to those
conditions (such as electrochemical measurements being done at 25 C, or
boiling points given at 1 atm. pressure) data taken out of the context
of the measurement conditions may be at best irrelevant, and at worst,
very misleading.
Cheers!
Rod Schaffter
------------------------------
Date: Wed, 5 Aug 1998 09:38:34 -0400
From: Herbert Bresler <bresler.7@osu.edu>
Subject: Re: sparge water acidification
Jeff Pharr asked "A question or two on the process of acidifying the sparge
water" in HBD #2788, Mon, 3 Aug 1998.
The first one was: What is everyone else doing to bring down the pH?
One simple answer is to use lactic acid. I get 88% lactic acid from my
local homebrew shop. It comes in a 4 ounce jar and lasts a long time since
you only need a small amount per brew (Columbus, OH city water usually
requires only about 1 teaspoon per 3 gallons of sparge water to acidify to
pH around 5.6). The other nice thing about lactic acid is that yeast will
consume it during the fermentation, so it has virtually no effect on the
finished product. (If you use a ton of gypsum, it will definitely affect
the finished beer, perhaps adversely.)
A word of caution: Handle 88% lactic acid carefully; after all, it is
concentrated acid and will burn skin, clothing, etc.
Good luck and good brewing,
Herb
------------------------------
Date: Wed, 5 Aug 1998 10:22:02 -0400
From: "David R. Burley" <Dave_Burley@compuserve.com>
Subject: Pharr Out Acidity, Stuck wine, reducung sugars
Brewsters:
Jeff Pharr is unsuccessfully trying to adjust the acidity of his sparge
water with Gypsum. Gypsum is a poorly soluble, neutral salt of calcium
and
sulfate ions and by itself in water won't do much to change the pH. The
reason gypsum works in increasing the acidity ( reducing the pH) of a
wort
is that the calcium ion from the gypsum reacts with various phosphate
salts
in the malt which are partially protonated. The even less soluble calcium
phosphate is precipitated and the proton released. Ergo the pH drops.
To adjust your sparge water I recommend food grade lactic acid, although
other acids like food grade phosphoric will also work. One problem with
phosphoric acid is that it may upset the calcium balance in the wort, so
that's why I stick with the lactic acid available from your HB shoppe.
Sparge water around 7.5 may cause the extraction of phenols from the husk
and parts of the endosperm toward the end of the sparge as the buffers
in
the wort no longer are concentrated enough to control the pH of the
sparge.
- ----------------------------
Matt garret has a wine fermentation that is stuck. Add yeast nutrient (
HB
store) and pitch another pack of yeast if the addition of the nutrient
doesn't do it.
- ----------------------------
A.J DeLAnge says:
"Dave Burley should be pleased to note that the ASBC Methods of analysis
has not 1 but 2 methods for determing reducing sugars."
I am , but I'm not surprised. Thanks for pointing this out.
For those who don't make the connection Clinitest measures reducing
sugars.
- ----------------------------
Keep on brewin'
Dave Burley
Kinnelon, NJ 07405
103164.3202@compuserve.com
Dave_Burley@compuserve.com
Voice e-mail OK
------------------------------
Date: Wed, 05 Aug 1998 08:25:49 -0600
From: Ken Schwartz <kenbob@elp.rr.com>
Subject: Gypsum & pH Adjustment
Jeff Pharr has messed with gypsum to try to adjust the mash and sparge
pH and asks:
> What is everyone else doing to bring down the pH?
> Should I just start buying gypsum in 50lb sacks?
> What are the problems associated with excessive gypsum usage in the
> mash?
> What are the problems with using sparge water with a pH up around 7.5?
The reason gypsum (calcium sulfate) works to lower mash pH is because of
a *chemical reaction* in the mash which liberates H+ ions (protons),
which is what makes acid, acid. In plain water no such reaction takes
place, and you might as well be adding sand or Kool-Aid.
Excessive gypsum will overload your beer with sulfate ions, which
harshens and dries bitterness. There are a very few styles (most
notably Burton Pale Ales) that can benefit from such an effect but in
most cases this is undesirable. Calcium Chloride is now more commonly
available than before, and is a better choice in beers that are
sulfate-sensitive.
Sparge pH should be lowered to create a chemical environment less prone
to leaching susbtances from the grain husks which can lend astringency
to the final product. A pH of 5.7 is a commonly-quoted target.
To lower sparge water pH, you can use food-grade acid. Your HB supply
store should have 10% phosphoric or 88% lactic acid available. The
amount of acid required depends on the composition of your water, so use
trial-and-error along with good pH strips or a meter to guide you.
Another suggestion is to prepare enough *distilled* or *RO* water for
sparging, then add malt extract at the rate of about 1 tablespoon per
gallon. Distilled/RO water is very "pure" water and its pH is easily
influenced from even small additions of acids or bases. Malt extract is
concentrated wort, which we know is an acid (acids have pH < 7.0, wort
is usually around 5 or so). I have found that this ratio of extract in
distilled water lowers the pH sufficently to safely sparge without
adding a lot of sugar (something like 2 points of gravity, probably less
than your starter is adding ;-).
- --
*****
Ken Schwartz
El Paso, TX
kenbob@elp.rr.com
http://home.elp.rr.com/brewbeer
------------------------------
Date: Wed, 5 Aug 1998 10:07:46 -0500
From: rlabor@lsumc.edu (LaBorde, Ronald)
Subject: RE: Clinit*st
From: Mark Riley <mriley@netcom.com>
>The horse is now very, very dead. ;-0
Yeah, you can test it's blood sugar with Clinitest and see if maybe that
killed it.
Ron
Ronald La Borde - Metairie, Louisiana - rlabor@lsumc.edu
------------------------------
Date: Wed, 5 Aug 98 08:34 PDT
From: caburns@egusd.k12.ca.us (Charley Burns)
Subject: Commercial Starters
Peter Gilbreth comments in hbd#2788:
In the case that a commercial brewery needs to start anew with
their yeast, they are not likely to build up from a smack pack, but rather
they will purchase a large amount of centrifuged cells. And when they do
need to propogate, they will likely have off flavors in the first few
batches that may need to be blended with subsequent brews.
[me] The commercial brewers that I have spoken with regarding this buy very
large smakpaks from Wyeast and propagate their yeast with small yeast
propagation batches prior to pitching the slurry into a **production** batch
of beer meant for public consumption. Thus avoiding the off-flavors in the
first place. Do you specifically know of a commerical brewer that blends
their beer to "hide" off flavors due to low pitching rates? Or was this
conjecture?
Charley
------------------------------
Date: Wed, 5 Aug 98 10:13:56 CDT
From: jwilkins@wss.dsccc.com (John Wilkinson)
Subject: RE: coiled hose
Al wrote:
> Laurel writes:
> >In answer to Mark Swenson's question about dispensing from a keg at
> >relatively high pressure - you're right to use a longer dispense line,
> >but you might also try coiling it up several times (say, a 5-6" diameter
> >coil or as small as you can make it without kinking the tubing) to give
> >more back pressure.
>
> Are you sure about this? I don't see how coiling would increase back
> pressure...
Sam wrote:
>It seems to me that a tight-enough coil would bend the profile of the
>tubing out of round, effectively reducing the diameter of the hose. An
>oval of a given circumference has a smaller area than a circle of that
>circumference. So this may work.
Maybe I am just dense but I thought what Laurel meant was to use a long enough
hose to drop the pressure and that coiling it was a way to fit it into the
space available.
John Wilkinson - Grapevine, Texas - jwilkins@wss.dsccc.com
------------------------------
Date: Wed, 5 Aug 1998 11:26:30 -0400 (EDT)
From: Some Guy <pbabcock@oeonline.com>
Subject: Re:Patron Saint of Brewing/Beer???
Greetings, Beerlings! Take me to your lager...
John Baxter Biggins <jbbiggin@mail.med.cornell.edu> asks:
> Anyone out there know who the patron saint of Brewing or Beer is (if
> there is one)???
Those would be Saints Dunlop and Flatulence, if I'm not mistaken.
No, but seriously: It's Karl Lutzen.
See ya!
Pat Babcock in SE Michigan pbabcock@oeonline.com
Home Brew Digest Janitor janitor@hbd.org
HBD Web Site http://hbd.org
The Home Brew Page http://oeonline.com/~pbabcock/brew.html
"Just a cyber-shadow of his former brewing self..."
------------------------------
Date: Wed, 05 Aug 1998 11:45:14 -0400
From: "Ludwig's" <dludwig@us.hsanet.net>
Subject: re: Holes in the fridge
If your not absolutely sure what lurks behind the sheet metal your about
to drill through. Drill a small hole using a drill depth collar to limit
the protrusion depth to minimum. Then probe around to make sure nothings
in the way.
Dave Ludwig
Flat Iron Brewery
SO MD
------------------------------
Date: Wed, 5 Aug 1998 11:02:14 -0500
From: "Joel Plutchak" <joel@bolt.atmos.uiuc.edu>
Subject: Harvesting Homegrown Hops
Oh gods of brewing, I approach ye on bended knee. (Was that OK?)
I'm in my first productive year of growing hops. The Chinook
are just now getting great cones-- long and large-- while the
Cascades cones have been around for awhile (smaller and rounder).
This past weekend I picked about an ounce of the first Cascades
because they seemed dryish. They smelled really nice, too.
However, after 5 days of air drying they just smell grassy.
What's up? Did I harvest too early? Too late? Dry too much?
Not enough? Not fast enough? Could growing conditions have
been suboptimal?
FWIW, they were papery and springy when I picked them, and
they lost *very* roughly (my digital scale measures in 1/4-oz
increments) 75% of their weight after drying. The strigs are
brittle. The cones were of various sizes, ranging from about
1/2" to 1" long. I can see the golden-yellow lupulin glands,
and when crushed they smell like Cascades.
Thanks in advance for any conjecture.
- --
Joel
------------------------------
Date: Wed, 05 Aug 1998 12:14:51 -0400
From: cdknotts@m3.sprynet.com
Subject: Microwave / Yeast Harvest ?/ Clubs ?
Microwave
Fred Wills wrote:
<For actual conventional starters, I usually mix the appropriate amount
of DME and water in a mason jar and nuke it in the microwave for about
20-25 minutes. Wicked easy and everything that touches the wort is
well sanitized (maybe even sterilized for a short while). Microwave
starters are so easy it makes me woinder why anyone would bother
canning wort.>
I too have great success with using a microwave for starter solutions.
I use a 1000ml Erlemeyer (sp?) flask, place it off-center on the
microwave carrousel, plug-in 5 to 8 minutes on high and let it go (a
true fire-and-forget process).
I also use the microwave to prepare my corn sugar priming solution when
bottling. I follow the same procedure however, a 3 cup Pyrex measuring
cup is used for the solution vessel.
No problems thus far with either.
Comments?
- -----------------------------------------------------------------------
Yeast Harvest
Does anyone out there use the inverted carboy fermentation technique to
harvest yeast? If so, please share your experiences.
- -----------------------------------------------------------------------
Clubs
Does anyone know of a Brew club registry other than the Brewery website
or Zymurgy magazine? Or, are aware of clubs in the Northern Virginia
area (South-Eastern Fairfax County / North-Eastern Prince William
County)?
I am at the point (finally living in the USA for at least the next 2
years) where I would like to associate with other brewers in a
Home-brew club. The problem is that there seems to be a lack of
interest in the area that I live. I have contacted clubs (via email)
that are located near by, but I get no response or a "clubs disbanded
due to lack of interest" message.
------------------------------
Date: Wed, 5 Aug 1998 12:18:14 -0400
From: "Kris Jacobs" <jtsnake@net-link.net>
Subject: Saturday's Brew
Thanks to all who speculated to me via email about my infected
batch.
I live in the Kalamazoo, MI area, and 95% of the time I pitch a six-
pack worth of bottle dregs yeast from Bell's Amber Ale. I love
Bell's yeast -- it works great. I have just recently got a great
contact -- now I can get quart jars FULL of Bell's yeast straight off
their fermenters. Whoohoo! This should solve any sort of
underpitching problems... ;)
As for sanitation, I use BTF @ about 25ppm, contact time of
anywhere from 3 minutes to 30. I suspect my first-ever try at
chilling with my CF chiller that I just built had something to do with
ruining that IPA. It was a train wreck to say the least -- I had major
flow problems, etc. plus I was well into "yeast harvesting" a sixer
and then some. Heh! I am back to immersion chilling until I can get
a pump, IOTW, until I get my RIMS set up.
Kris Jacobs
Galesburg, MI
------------------------------
Date: Wed, 05 Aug 1998 12:28:50 -0500
From: bob_poirier@adc.com
Subject: Boiler Sight Gauge Question/Manifold vs. False Bottom
Greetings!
** Boiler Sight Gauge Question **
Just got done reading HBD #2786 (OK, so I'm two days behind - at
least I'm not two MONTHS behind like I was two or three weeks ago!!).
I've got a question about the sight gauge Guy Gregory installed on his
converted 1/2 bbl. SS keg: Will the wort the fills the sight tube
cause any problems with infections, since it isn't boiled along with
the rest of the wort??
This has been bothering me for a while, and I haven't installed a
sight gauge on my boiler because I couldn't decided if I was being too
paranoid or not!
** Manifold vs. False Bottom **
I've got another hang-up regarding the difference in performance
between a lauter tun fitted with a manifold (constructed of 1/2 in Cu
pipe/fittings), and a tun fitted with a false bottom. I'm in the
process of converting a 1/2 bbl. SS keg into a mash/lauter tun, and I
can't decided which to use - the manifold is a LOT cheaper, but,
something in the back of my head keeps saying that a good false bottom
beats hell out of a manifold. Any thoughts??
TIA!
Brew On & Prosit!!
Bob P.
East Haven, CT
Home of Bubba's Bodaceous Basement Brewery
PS - Keep up the good work, people!! I've learned more about home
brewing since I subscribed to the HBD in April '98 than I EVER learned
since I started home brewing in '91. THANKS!!!
------------------------------
Date: Wed, 5 Aug 1998 11:42:48 -0500 (CDT)
From: Samuel Mize <smize@mail.imagin.net>
Subject: Peter on repitching; underpitching; recipe conversion; Infected Primary
Greetings to all.
Peter Gilbreth <barleywine@prodigy.net> wrote a paragraph I found
confusing. Was Lyn saying that using sediment from either fermenter
(primary or secondary) would select over time for non-flocculent yeast?
I'm not arguing yea or nay, I just didn't quite follow your meaning.
- - - - - - - - - -
"Brian Wurst" <brian@mail.netwave.net> says:
> I would wager that most homebrewers underpitch almost every time they
> brew...Could this be the origins of THT (That Homebrew Taste)?
You mean the one we like? :-) It's probably a secondary factor, at least,
in some less-satisfactory tastes.
On the other hand, there are a couple of comments in That Same Issue of
HBD about "adequate" pitching providing a "clean," non-estery beer. I
personally like lots of fruity, flavorful esters. On the other other
hand, this would hurt me in competitions.
- - - - - - - - - -
"Dave Russell" <drussel3@ford.com> asks about using his own hops to match
a hopped extract. Wow, best of luck, this will probably take you several
experiments. Then you'll have to drink them up, darn. Your hop
utilization (how much of the available bitterness you actually extract
from the hops) will vary based on how much you boil, for how long and how
vigorously, how much malt is in the boil, and a lot of other factors.
Also, John Bull extracts don't ferment out as completely as some other
brands (although some others leave even more sweetness). You'll want to
use John Bull unhopped extract to match perfectly.
I'll let those who know more about hops give you specific advice. I'm
just pointing out that you may have a tough time matching it perfectly.
On the other hand, you can easily come up with an excellent beer you will
enjoy, if you don't worry about matching it all that precisely.
- - - - - - - - - -
"Kris Jacobs" <jtsnake@net-link.net> has an infected primary, and says:
> I intend to throw the whole batch out, I just have to bring myself to
> do it sometime. Probably Saturday morning, when I will whip up a
> quick and dirty low-gravity pale ale.
I'll grant up front that I'm paranoid, but I personally would dump it and
sanitize the primary (and the drain) the day before. I don't really want
a 5 gallon infection culture hanging around the house the day I brew. You
may also want to spray-disinfect the area you put your fermenters in.
- - - - - - - - - -
From: randy.pressley@SLKP.COM:
> I brewed a batch of India Pale Ale and added a handful of oak chips ...
> I tossed them directly into the secondary for about 10 days wearing only
> their birthday suit.
You should have worn plaid.
- - - - - - - - - -
To Mark Riley: it's Dracula's horse. It never stays dead for long.
On the other hand, if it's a diabetic Clydesdale, we can test with perfect
accuracy whether our Budweiser clone is ready.
Best,
Sam Mize
- --
Samuel Mize -- smize@imagin.net (home email) -- Team Ada
Fight Spam: see http://www.cauce.org/ \\\ Smert Spamonam
------------------------------
Date: Wed, 5 Aug 1998 10:53:58 -0600 (MDT)
From: William Graham <weg@rmi.net>
Subject: Refractometer
Hello-
In this month's BT, there is a small ad from a California company
called "Grain Robbbers" which is trying to sell a refractometer for the
purposes of measuring sg. Does anyone know anything about this device like
how is it used?, is it accurate enough?, and would this be a useful thing
for a gadget-tolerant home brewer such as myself?
TIA
Bill
"...the only way to deal with bureaucrats is with stealth and sudden
violence." - Butros Butros-Ghali
------------------------------
End of HOMEBREW Digest #2790, 08/07/98
*************************************
-------
