---

	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:
  Yeast Q-Wine Part 1- Dr. Cone ("Rob Moline")
  Yeast Q-Wine Part 2- Dr. Cone ("Rob Moline")
  The Jethro Gump Report ("Rob Moline")
  RE HBD 3304 (Pump problems ) ("David G. Humes")
  Smooth Stout (Gravel Stephen E NPRI)
  Apology... Must mess ("Jack Schmidling")
  cardamom (Marc Sedam)
  NYC Trip ("Philip J Wilcox")
  bottle storage ("S. SNYDER")
  Hot water pump, Burrabadoo, Manhattan, Oversulfited must (Dave Burley)
  Re: DakBrews question on iodophor (Robert Arguello)
  Yeast Q's- Rick Olivo- Dr. Cone ("Rob Moline")
  Yeast Q's- Ernie Baker- Dr. Cone ("Rob Moline")
  Yeast Q's- Pete Czerpak- Dr. Cone ("Rob Moline")
  re: temps/more ... (Lou.Heavner)
  Pump Questions (RCAYOT)


* Beer is our obsession and we're late for therapy!

* 18th Annual Oregon Homebrew Festival - entry deadline May 15th
* More info at:  http://www.hotv.org/fest2000

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Date: Sun, 23 Apr 2000 23:00:17 -0500
From: "Rob Moline" <brewer at isunet.net>
Subject: Yeast Q-Wine Part 1- Dr. Cone

Folks,
	Though this is a wine yeast question, I thought that you would find it of
interest...I know I did. It is broken into 2 parts, due to length....
Rob

Dear Dr. Cone:
There are many yeasts available for winemakers, all having some desirable
qualities to fill a particular niche.  Could you please tell me which yeast
or yeasts (if the answer is different for red and white wines) best meet
the
following characteristics.  Perhaps no yeast will meet all these
characteristics, so the answer may be a compromise:

Vigorous fermenter that starts fermentation rapidly.

Produces little volatile acidity.

Produces little sulfur dioxide.

Little acetaldehyde is left at the end of fermentation.

Readily goes through malo-lactic fermentation.

Little sugar is left over at the end of the fermentation.

Not prone to produce sulfides.

Efficient at utilizing nutrients.

Neutral, or if possible, positive sensory qualities.

Thanks very much for your help.
Phil DeVore (ped at qtm.net)
Long-time home winemaker, retired chemical engineer and winery consultant.


Phil DeVore,
It would be great if there was a yeast that had all of the attributes that
you have on your wish list, it would take a lot of the responsibilities off
of the winemaker.  However, a great deal of what you are asking for is
controlled by the winemaker.  Lets go through some enological
characteristic and see how the winemaker can help the yeast.  My goal has
always been to produce and maintain a healthy yeast cell.  You will be
surprised at what a wonderful job a healthy yeast will do for you.  We
produce about 150 different yeast strains for the wine industry each year.
Each strain has a little different characteristic.

There has been an evolution in the selection of wine yeast.  15 years ago
we were satisfied with four strains:  Red wine, white wine, cold temp. and
Champagne.  10 years ago we became a little more sophisticated with better
analytical tool and began to isolate and select strains that could fall
into three groups: 1). Yeast that produced fermentative character to the
wine (as in 'vin nouveau'), 2).  yeast that tend to be neutral as desired
by most Champagne houses and 3).  yeast that do not produce fermentative
character to the wine but promote the release of bound flavor and aroma
compounds that are already in the grape.  About 5 years ago we began to
build on 1). & 2). by looking for yeast that increased acidity (succinic
acid) where needed, reduced acidity where needed,  assisted in color
extraction,  assisted in color stability,  removed color,  produce
polysaccharide and manoprotein production,  improve mouthfeel, cell wall
hydrophobicity / lipophobicity, friendly to ML fermentation, unfriendly to
ML fermentation (also protects against other spoilage bacteria), specific
for Grenache, specific for Syrah.  The list grows every day as the wine
research institutes, around the world, improve their understanding of both
the yeast and the grape. Now you have an array of yeast strains to use as a
tool to tailor your wine to your style.


Vigorous fermenter that starts fermentation rapidly.

There are only a few strains on the market that are slow fermenters
(i.e.Lalvin SIMI White). The exquisite character that they give to the wine
makes it worth while for some winemakers to make the added effort and sweat
that goes with their fermentation.  The remainder of the yeast strains have
been selected because they are strong fermenters.

Built into the Dry Yeast at the factory is a large amount of trehalose that
should get all strains off to a good start  With proper attention given to
rehydration procedures, attemperation of the yeast before inoculation,
adequate inoculation size, adequate nutrients throughout the fermentation
and Oxygen available for the yeast during the first 24 - 48 hours of the
fermentation, all yeast should get off to a good healthy start and ferment
steadily until there is no residual sugar.

Yeast like Lalvin DV10, K1V-1116. EC-1118, R2, L2056, L2226, 71B-1122
(just as a starter) are all good, strong fermenters.

Produces little volatile acidity.

VA is usually produced by spoilage bacteria and certain wild yeast.
A deficiency in Pantothenic acid will sometimes cause the yeast to produced
increased amount of VA.
As you increase fermentation temperature from 50F. up to 90+F. the VA
production increases.  As you drop the fermentation temperature below 45F.
the VA increases.  As the initial sugar in the must  increases above 25
brix the VA increases as in Late harvest and Ice Wine (up to 50% sugar).



Return to table of contents


Date: Sun, 23 Apr 2000 23:02:03 -0500
From: "Rob Moline" <brewer at isunet.net>
Subject: Yeast Q-Wine Part 2- Dr. Cone

Part 2 Wine Q

Produces little sulfur dioxide.

This is strain related. Some yeast produce as low as 1 ppm i.e. Lalvin
Wadensville 27. Some produce around 30 ppm: i.e. Lalvin EC-1118.  Some go
as high as 60 - 100 ppm (not in our collection) but has a place for some
white wine stability and definitely prevents ML and other spoilage
bacteria. Because of SO2 labeling laws, these high SO2 strains have not
been explored.

Little acetaldehyde is left at the end of fermentation.

Acetaldehyde is part of the natural pathway sugar takes as it is converted
to alcohol.  A deficiency in Vitamin B1 will cause a buildup in this
intermediate pathway product causing the yeast to expel some of it. The
addition of SO2  causes the yeast to produce acetaldehyde to neutralize it.
This is the yeasts natural mechanism to protect itself against the harmful
effects of SO2. So be judicious in the SO2 addition.

Readily goes through malo-lactic fermentation.

There does seem to be friendly and unfriendly yeast to Malo lactic bacteria
fermentation.  This is not clearly understood.  There is a relationship
between yeast production of high levels of SO2 and poor ML fermentation.
There is not a lot of data on the level of SO2 production by each strain.
The strain Lalvin EC-1118 produces up to 35 ppm SO2 and seems to be
involved with slow ML fermentations and a yeast like Lalvin Wadensville 27
produces around 1 ppm SO2 and is noted to encourage ML fermentation. High
SO2 producing yeast can be used as a tool to minimize or eliminate ML
fermentation if this is your style. It also assists in controling other
spoilage bacteria.

There are factors other than yeast that cause problems with ML
fermentation: low pH (<3.1), low temperature (<60F) and high alcohol
(>12%). There are several new strains of yeast that address these problems.
There is also a selection of ML bacteria that offer a range of flavor
profiles.

There are other problems with ML fermentation such as octanoic and decanoic
acid produced in some primary fermentation.These acids also harm the yeast
causing slow and stuck fermentations.


Little sugar is left over at the end of the fermentation.

All health yeast should ferment all of the sugar. Some fermentations,
especially chardonnay, occasionally produce octanoic and decanoic fatty
acids that are toxic to the yeast and will cause stuck fermentations.
Sometimes the addition of yeast hulls will tie up these two compounds and
allow the yeast to continue to ferment.

Most stuck fermentation leaving  residual sugars are caused by 1). Ferment
at too high a temperature causing the alcohol to become very toxic, 2).
nutrient deficiency in the must, (primarily Nitrogen), will result in a low
yeast growth leaving one yeast cell doing what several should be doing.
Also, low nitrogen levels will cause the yeast to be very susceptible to
alcohol toxicity near the end of the fermentation. 3). Yeast require air
(oxygen) during the growth phase to produce lipids that act as growth
factors and will also protect the yeast against alcohol toxicity near the
causes problem fermentations, 5) poor yeast rehydration and inoculating
practices.

Not prone to produce sulfides.

Except for a few mutated yeast, H2S is a natural metabolic pathway in the
production of two of the sulfur containing amino acids.  The big problem is
to minimize the excess production of  H2S.  An adequate supply of nitrogen
(DAP and autolyzed yeast) throughout the first half of the fermentation
goes a long ways to achieve this. An unhealthy yeast cell will die
prematurely and cause the production of mercaptans (sulfury type compounds)
at the end of the fermentation.

Efficient at utilizing nutrients.

Every strain has built into its DNA instructions its own efficiency in
nutrient utilization.  Some strains require twice as mush nitrogen to do
the job as other require.  We have suspected this for several years.  Now
research instituted are documenting this for every strain.  The same goes
for O2 requirements of each strain. We will be offering this information on
each of our strains within 12 - 18 months.  High brix and low pH must gives
the yeast lots of trouble utilizing the nitrogen.  Must with less than 300
ppm Potassium has troubles growing.

Neutral, or if possible, positive sensory qualities.

Lalvin DV10 and EC-1118 are two strains of yeast that are very strong
fermenters tending to be neutral in fermentation aromas. They are excellent
yeast for base and secondary Champagne fermentation. These two yeast are
good for juices that are already rich in flavors and aromas and need not
help from the yeast.

Lalvin 71B-1122, K1V-1116 and L2056 are only a few that contribute to the
bouquet.
Lalvin BM45, RC212 and BRL97 are only a few that assist in color extraction
and stability, product polysaccharides and manoproteins that contribute to
mouth feel
Lalvin VL1 is an example of a strain that frees up bound flavors in the
grape.

Clayton Cone





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Date: Mon, 24 Apr 2000 00:06:35 -0500
From: "Rob Moline" <brewer at isunet.net>
Subject: The Jethro Gump Report

			The Jethro Gump Repor

>From: Jim Liddil <jliddil at vms.arizona.edu>
>Subject: Re: iodophor, AHA Bashing :-)
>Oh let's go to the stoning.  Well though Rob moline is on the AHA board
>you will note that under is title for lallemand he brought dr. cone here
>and not to the useless aha forum.  Did the Siebels guys show up at the AHA
>forum?  nope, hbd.  <SNIP>
>Jim Liddil

Sir,
     I wear many hats, and try to contribute to all the groups and
activities that I care about...in some way or another.
     That's why I wanted Lallemand to contribute the BOS prize for MCAB
2000...and the Siebel Scholarship for members of the AHA. That's why I
occasionally call HBD'rs and Lallemand beer questioners on the phone when I
think it would help. Sad to say, I haven't been as active on the IBS Forum
as I was when working professionally as a brewer, but that's another story.
I had an idea that I think would help TechTalk, linking the experts that
participate on the IBS Forum to TechTalk, but whether or not it can be
implemented is yet to be seen. But this is all beside the point...

     Quite honestly, I find it curious that you would choose this time to
denigrate an organization that Mr. Sedam felt was changing along the lines
you desire!

     And I don't believe it to be true that the HBD refused any money from
anyone...I had suggested to the AHA BOA that we make a donation, and while
there was a general agreement to this, it couldn't be done with other more
pressing accounts to be paid. Pat did say that the AHA couldn't expect any
higher level of acknowledgement for any possible gift than that
traditionally assigned...this is only fair and that would have been fine
with me.

     The 'Siebels guys' you refer to came here 'cos I asked them to....Dr.
Cone did the same......'cos they were kind...and happy to generously share
knowledge with brewers...

     As a Member of The AHA BOA, you offend my efforts here, by taking my
intentions for granted...My future efforts could just as easily be assigned
elsewhere....
     Further, I announced my affiliation with Lallemand, so that all would
know where I stood....and avoid the appearance of any impropriety.

     I am trying to build bridges with brewers, no matter where they
congregate......It has always returned more to me than it costs.

Jethro Gump

Rob Moline
AHA BOA
Lallemand
Siebel Alumni
IBS
MBAA
MCAB Steering Committee

"The More I Know About Beer, The More I Realize I Need To Know More
About Beer!"



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Date: Mon, 24 Apr 2000 01:19:52 -0400
From: "David G. Humes" <humesdg1 at earthlink.net>
Subject: RE HBD 3304 (Pump problems )

Greetings,

Brent describes various pump problems:

1.  Difficulty priming.

    This really should not be a problem, but it can take a little patience.

2.  Pump losing its priming.

    I have experienced this problem.  I do not suspect that it is a leak as
others have suggested or cavitation.  I think that it is caused by dissolved
gasses that break out of solution due to the lower solubility at elevated
temperature and reduced pressure created on the suction side of the pump.
The dissolved gasses accumulate in the impeller chamber causing the pump to
lose its prime.  You can confirm this with a little experiment.  Try
preboiling your sparge water for about 20 minutes.  This will drive off most
of the dissolved gasses.  Let the water cool down to your normal sparge
water temperature, and then run the pump and see if it loses its prime.  If
it does, then you probably still have a leak.  Otherwise, it's dissolved
gasses coming out of solution.

    I used to preboil all my brewing water.  When I did this I did not have
the problem you describe pumping sparge water.  However, when I started
filtering rather than preboiling, the problem came back with a vengance.  If
you orient the head of the pump so that the inlet is at the bottom and the
discharge is at the top, the problem can be minimized.  I've found in this
configuration that bubbles still collect in the impeller chamber, but if you
leave both the kettle drain valve and sparge pump discharge valves open and
shut off the pump, the bubbles will rise up the discharge line and clear the
pump.  You can change the pump head orientation easily by removing the 4
screws on the front of the pump body and rotating the head to the desired
orientation.  This keeps the oil tubes for the motor vertical.

3.  Stuck runoff

    Chances are you were recirculating too fast.  Throttle back on the pump
discharge valve.

4.  Cleaning

    I flush mine with lots of clear water and then blow it out with
compressed air.  CO2 will due nicely as well.  If you don't do this some
water will stay in the impeller chamber and may grow some funk.  It's
probably not a problem if you flush it out good before you use it next time.

- --Dave




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Date: Mon, 24 Apr 2000 08:32:13 -0400
From: Gravel Stephen E NPRI <GravelSE at Npt.NUWC.Navy.Mil>
Subject: Smooth Stout

Hi All,

I brewed a Foreign Extra Stout recently and it came out pretty good.  It
took second place in the SSBC Brewoff 2000.  However, I sampled the first
place winner and noticed a nice smooth almost creamy texture to the beer
that mine was lacking, it reminded me of the Young's Double Chocolate Stout
(although, not quite as good).  I have several questions:

1.  How do they get the smooth creamy flavor?

(I was told that an addition of Lactic Acid would do the trick.)

2.  If this is correct, how much Lactic Acid would be recommended for a 5
gallon batch?

3.  When should it be added during the brewing session?

4.  Is Lactic Acid the key ingredient, or is there another way to achieve
this smooth creamy texture/flavor? 

Thanks in advance for any advice/assistance I receive.

Steve

"Homebrew, it's not just a hobby, it's an adventure!" 


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Date: Sun, 23 Apr 2000 22:34:40 -0500
From: "Jack Schmidling" <arf at mc.net>
Subject: Apology... Must mess

From: Dan Listermann <72723.1707 at compuserve.com>


> He used 3 tsp of sodium bisulfite powder to sterlize the must.  Needless to
say, it won't ferment despite a prolonged peroid of venting.  Is there any
hope for the must?....

Tell him to hang in there.

Once upon a time, a friendly hb retailer told me to use 1 tsp (powder)  per
gallon of must.  I didn't bother double checking on this and used 5 tsp in a 5
gal batch.  It smelled ghastly and I looked it up in other refs and found the
number to be 1 tsp for 5 gals and was really upset.

I pitched a small sample of the yeast in a small sample of the must every day
until it started fermenting and then pitched the whole batch.  It was a special
yeast that I didn't want to lose either.

Don't recall for sure but it was at least 5 days.

js

PHOTO OF THE WEEK  http://user.mc.net/arf/weekly.htm
HOME: Beer, Cheese, Astronomy, Videos  http://user.mc.net/arf





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Date: Mon, 24 Apr 2000 09:41:44 -0400
From: Marc Sedam <marc_sedam at unc.edu>
Subject: cardamom

A-B hasn't been "sitting" on this since 1981...it's been a
publicly available document since 1983, tho'.  The patent is
designed to protect very light lagers from being sunstruck
in either the bottle or the glass.  Of course, if you let
Budweiser heat up in the sun it tastes nasty for reasons
other than skunked flavors.

You could always make up a "tincture" by soaking the
cardamom in grain alcohol, but it might change what you get
out of it.  Dunno.

The patent expires in a year.  To avoid infringing on a
useful AB patent, I'd skip the experiments until next June.
;-)

Cheers!
Marc



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Date: Mon, 24 Apr 2000 10:06:08 -0400
From: "Philip J Wilcox" <pjwilcox at cmsenergy.com>
Subject: NYC Trip

Digest,

Yes, I am still working on my notes from Germany...In a nutshell, Cruising for
Koelsh bars is my kind of drinking! Pilsner Urquell in Pilzn is the best beer
I've ever had anywhere. Its easier to drink than water! U Flecku in Prauge was
the coolest brewpub on the whole trip! Munich is too big to properly explore in
a month, and I only had a day and a half--Best Munich Beer was Andechts. Best
Helles, Spatan and the previous. Best Wheat, Frankenkaiser, Best Maibock (and
Brewpub)--Forschungsbrauerei, Biggest suprise-Salavator on tap (ligher in color,
body, and preceptable alcohol than the US Bottled counterpart) Biggest
disappointment, Brewpubs. In general they are no better than ours--Very Hit or
miss. If your on a limited time budget, skip them and stick to the Big Brewers
beergartens and Kellers. All of which were top notch.

My next trip is NYC this Saturday till Tuesday. My wife has a conference at the
Downtown Manhattan Hilton (1335 Avenue of the Americas).  I suspect that since
my father-in-law Bailed out, I being the lone male (9.5 mo old daughter, wife,
her Mother, Aunt and Sister) I will get (demand) more time to do some
beerexploration. So Where should I go? I have heard that Manhattan is not a
brewpub mecca, but being the largest import/export city in the world, has to
have some beer advantages somewhere. Quality Multi-taps???  Is there a place
like Sam's Wherehouse in Chicago??? All help, hints, and tips appreciated. and
if any of you NYC HBD'rs want to meet for a Pint somewhere, I am definatly up
for that. G DeP--We missed you  at  the MCAB, care to come to the bigtown for beer
cruising????

Phil WIlcox





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Date: Mon, 24 Apr 2000 11:31:23 -0400
From: "S. SNYDER" <SSNYDER at LBGHQ.com>
Subject: bottle storage

Greetings-

I just joined the list a few weeks ago.  I have been homebrewing for about 2
years now and have accumulated quite the repository of bottles, mainly 12
oz'ers but some Grolsch w/ceramic tops, etc.  All bottles are routinely
rinsed (all have been delabelled) free of all visible sediment etc.
However, my storage of bottles concerns me everytime I go to bottle because
I am afraid of contamination by bacteria.  The bottles may sit on the shelf
for 6 months or so before I sanitize them just prior to bottling.  Should I
cover the bottles over the long period, or, if they are clean and dry, can I
just sanitize, rinse, and fill?

Thanks in advance for the help.

Scott Snyder
ssnyder at lbghq.com

"The eye seldom sees what the mind does not anticipate."



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Date: Mon, 24 Apr 2000 11:51:16 -0400
From: Dave Burley <Dave_Burley at compuserve.com>
Subject: Hot water pump, Burrabadoo, Manhattan, Oversulfited must

Brewsters: 

No pump expert am I, but with very hot water the pump can cavitate as the
water boils in the low pressure IN side if the input is limited in flow far
below the delivery volume of the pump. Non? Is your input restricted? How
hot is the water?
- --------------------------------------------------------
Phil, you do know what "Burrabadoo" means in Abo, don't you?  
- --------------------------------------------------------
Jeff, I can only add one thing which will improve your Manhattan, IMHO. Add
a small amount of the maraschino cherry juice.
- --------------------------------------------------------
Dan, other than adding chlorine to your customer's oversulfited must ( Just
kidding), I can suggest this procedure:

Dilute a small portion such that the sulfite concentration is about 30 ppm.
Add fresh yeast and get this fermenting. Add the high sulfite batch a bit
at a time to keep the sulfite at 30 ppm ( which the yeast can stand) and
the CO2 formed in the fermentation will sweep out the excess sulfite as SO2
from the acidic wine. Each day add some more.  As this addition goes along,
more and more of the oversulfited batch can be added, so it will only take
a few stages of this addition. I do not recommend pouring it through the
air as others suggest. This wine will be as good as the original
concentrate allows.

An alternative is to start another fermentation with the same kind of
concentrate and add portions of the sulfited batch. This will be faster and
no dilution.
- -------------------------------------------------------
Keep on Brewin'

Dave Burley
 .


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Date: Mon, 24 Apr 2000 09:35:16 -0700
From: Robert Arguello <brewhawk at pacbell.net>
Subject: Re: DakBrews question on iodophor

ON: Sat, 22 Apr 2000 09:06:11 EDT
 DakBrew at aol.com 
Subject: RE: Roberts RE: Jeff's queation on Iodophor

==Robert is this a direct quote? 
==
==He said that the solution should be renewed when the amber color
fades, or 
==after 24 hours ... whichever comes first.<<

==If it is I would interpret the word Renewed to mean small amounts of
Iodophor 
==added to bring the solution back up to 12 of 25 PPM. Most homebrew
shops sell 
==test strips for testing iodophor solutions. 

==Dan K

No, it wasn't a direct quote.  I didn't have the exact wording he used
in front of me at the time, so I pretty much para-phrased. If it were a
direct quote, the word renewed would have actually been "replaced". 
 
However.....

We did discuss "refreshing" the iodophor solution with subsequent
additions of iodophor concentrate. While this is possible and is done to
some extent, we both concluded that the practice on the homebrewing
scale was problematic. You CAN refresh or renew the working solution by
adding more iodophor but I would suggest it only be employed when
refreshing a working solution that has NOT been subjected to any protein
loading. In other words, only to an unused working solution that has
lost its amber color or older than 24 hours. "Refreshing" the solution
might be the ticket to folks like Mr. Renner, who earlier wrote to
mention that he likes to keep a solution in a spray bottle.

As to the test strips. I did experiment with some a while back and found
them to be vague and difficult to interpret. YMMV as part of my problem
with them may have been related to my faulty color vision. 

Robert Arguello
brewhawk at pacbell.net  (Please note new email address, finally switched
to DSL)


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Date: Mon, 24 Apr 2000 15:51:07 -0500
From: "Rob Moline" <brewer at isunet.net>
Subject: Yeast Q's- Rick Olivo- Dr. Cone

Dear Sir:
In virtually every brewing text I have ever read, there are warnings
against reusing dry yeast. The rationale for this is perhaps best summed up
by Dave Miller:
"Do not repitch slurries from dry yeast. Because all dry yeasts contain
some degree of contamination, and because the contaminating organisms will
grow from one pitching to the next, the only safe course is to use dry
yeast on a one-shot basis."
However, since I have begun maintaining a yeast ranch for members of the
on-line brewing fraternity, the Brew-Rats, I have noticed that dry yeasts I
have examinined under the microscope have been at least as "clean" as yeast
cultures derived from liquid yeasts. In any event, wouldn't it be possible
to eliminate the entire question by use of the single-cell origin colony
harvesting method?
"Find a single colony on the original ager plate that is physically
isolated from all the other colonies on the same plate. This colony is
homogeneous in the sense that all the cells degenerate from the same
parent. Thus this can be considered as a pure culture" (Nam Sung Wang Dept.
of Chemical Engineering  University of Maryland)
The same instructions are given in the "Advanced Yeast Culturing for
Homebrewers:
"Using a plate you can also "cone" your yeast stocks so that they originate
from a single colony of yeast. This is a sure way of getting rid of
potential bacterial contaminants..."
The question is this; has this caution, as outlined by Miller, been
overblown, at least using the procedures outlined by Wang and in the
Advanced Yeast Culturing for Homebrewers document? I haven't been able to
note any contamination of yeast cultures derived from dried materials. Is
it possible that technical production improvements have made this advice
obsolete, at least for those of us who "yeast ranch" rather than merely
wash yeast for short-term storage?
Your comments on this subject will be most welcomed.
Rick Olivo


Rick,
Until a few years ago the quality of the Active Dry Yeast for beer making
was not up to the rigid standards required by the brewing industry.  The
beer yeast was marginally satisfactory for a one time use but not advisable
for repeated pitching as Miller noted.  That was satisfactory for many home
beer makers because there was no interest in repitching.  In recent years,
companies like Lallemand's Dan Star, have made dramatic improvements in the
quality of their beer strains. The wild yeast and bacteria levels now meet
the rigid standards of such well know brewing institutes as Weihenstephan,
Siebel, Herriot Watt and others.  You should feel very confident in being
able to repitch the Dan Star beer yeast as often as you repitch your liquid
yeast.  However,  we feel that it is prudent practice to limit the
repitching to two or three times at most.  Even the big breweries, with all
of their sanitary savvy,  limit their repitching to less than 6 times   The
cost of dry  beer yeast is such that  it is economical to maintain minimum
repitching practice.  Many brew pubs do not attempt to recover yeast for
repitching, they just rehydrate and pitch fresh each time.

I am pleased that you have noted the marked improvement under the
microscope.

I have never been an advocate of single cell cultures. I have always
isolated several (15 - 20) colonies and studied each separately in test
tube and under the microscope.  When I was satisfied that all were OK, I
would then blend  into one culture.  This would prevent the isolation of a
single strain that would be mutated or might have a weak gene.

Fermenting from a packet of ADY Beer Yeast is very simple.  Fermenting from
a single cell is rather involved. I realize that many of you like the
challenge of preparing isolates and liquid cultures. Go to it.  When the
excitement and joy wears off, remember; there is ADY beer yeast.

I hope that Dr. Nam Sung Wang did not really mean that "all cells
degenerate from the same parent." Also, I believe that "Using a plate you
would also "clone" not "cone" your yeast stock- - - - - - .

Originating from a single pure colony of yeast is the first step in getting
rid of potential bacterial contamination.  Good laboratory and sanitary
practices are equally important.  You would be surprised how many single
yeast colonies contain bacteria when you streak from an infected wort.

Miller's caution was well taken several years ago but is not as apropos for
all suppliers of ADY beer yeast today.

Clayton Cone


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Date: Mon, 24 Apr 2000 15:52:21 -0500
From: "Rob Moline" <brewer at isunet.net>
Subject: Yeast Q's- Ernie Baker- Dr. Cone



From: erniebaker at webtv.net
Subject: Dr Cone, Dry Yeast Amounts?
Dr Cone
My question is concerning the proper amount of dry yeast to pitch to a 5
gallon batch.
Years ago it was always 1 (5 gram packet) to 5 gallons. A couple years
ago it was two 5 gram packets. At present it has been recommended to
pitch 15 or 20 grams of dry yeast.
I believe its time to issue good firm advice on the real amount of dry
yeast to pitch.
(Ale & Lager)..
Thanks for sharing your knowledge..
ernie baker
29 Palms, CA


Ernie,
I am glad that you brought this to my attention.  It would be neat if there
could be a label with a single inoculating rate that would satisfy all beer
makers and all worts.  The initial instructions for inoculation rates came
from the Beer Kit makers 10 - 20+ years ago.  They were well aware of the
sensitivity of the home beer maker to cost, so they offered the minimum
amount of yeast possible to do the job.  A few pennies more to cover the
cost of adding more yeast would lose them many customers. Today the kit
makers and the beer yeast producers are aware that the home beer maker is
willing to pay for quality and increased amount of yeast for pitching if it
is needed to give improved control over the fermentation.  Both are
beginning to respond.  Some label changes have already been made in
response to the trend to increase the inoculating rates.  Others will be
made in the near future.

Built into the ADY Beer Yeast  is a large trehalose reserve that gets the
freshly rehydrated yeast off to a good start.  It does not require as high
a cell population for pitching as it does for the repitching.

For a 10 Plato wort, I would be comfortable with two packets / 5 gallons
wort.  If you are satisfied with the fermentation rate and the taste of the
finished product you should stick with the 2 packets / 5 gallons. This will
give you about eight million yeast cells per ml. of wort.  If you are not
happy with the fermentation rate and the attenuation of your particular
wort then you should experiment with 3 or more packets.

If you go to a higher gravity wort and or dark wort you will need to
experiment with  higher pitching rates.

Clayton Cone


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Date: Mon, 24 Apr 2000 15:56:44 -0500
From: "Rob Moline" <brewer at isunet.net>
Subject: Yeast Q's- Pete Czerpak- Dr. Cone

From: "Czerpak, Pete" <Pete.Czerpak at siigroup.com>
Subject: yeast questions on flavor profile
A few yeast questions that resulted from some competition comments:
1) Is the Wyeast Fullers strain, 1968, thought to throw off deacetyl type
compounds? Could use of about 10% flaked maize contribute to this taste?
2) What would low temperature conditions do to the flavor profile of the
Wyeast Weihestephen yeast in terms of phenol, clove, banana tastes?  Are
these sensitive greatly to a 62deg F ferment temperature?
Thanks for the help.
Its about time to be brewing again.
Pete Czerpak


Pete ,
I have no experience with Wyeast Fuller Strain 1968 so I cannot comment on
it.  I will make the comment that  Wyeast, White Labs and G.W.Kent Inc are
excellent sources of liquid yeast.

It is not uncommon for yeast to produce diacetyl.  Studies have shown that
there is a doubling of Diacetyl  production with the increase of cereal
adjuncts in the wort from 20 % to 40% and another doubling when the adjunct
is increased to 50%. So it is possible that a 10% addition of flaked  maize
would result in a slight increase in diacetyl.  It is interesting to note
that yeast produce diacetyl during the early part of the fermentation and
can in turn consume the diacetyl at the end of the fermentation if the
yeast are alive and healthy.

Because diacetyl is so commonly produced, at some level,  during the
brewing fermentation, most brewmasters  are prepared for it.  They include a
"diacetyl reduction stage" a secondary fermentation at the end of the
fermentation for every batch either in the same fermenter or in a separate
tank.  The more active the yeast, the higher the cell count, the warmer
the temperature, the faster will be the diacetyl reduction. Usually 1 - 3
days is scheduled to reduce the diacetyl and other procusors to a level
below 0.1ppm.

If you detect diacetyl at the end of fermentation, you should allow the
yeast  a day or two to remove it before filtering.  If you note the
diacetyl after filtering you should add fresh yeast to the beer and allow a
few days for the yeast to reduce it.  A trace amount of fresh wort would
assist the new yeast to do the job.

2. I have no experience with the Wyeast Weihenstephen strain so I cannot
comment on what it can do.  I am assuming that you are asking about cold
conditioning of the yeast at the end of the fermentation.  I can say  that
the phenols come from the mashing and will probably not be effected by cold
conditioning.  Cold temperature conditioning should have little effect on
the 'clove' or 'banana' character of the beer.

Clayton Cone



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Date: Mon, 24 Apr 2000 15:55:15 -0500
From: Lou.Heavner at frco.com
Subject: re: temps/more ...

     Oops!  You should always take the words "must always" with a grain of
     salt.  And actually, I was referring to temperature boosts, not
     dough-in, so heat of hydration would have already been released.  But
     it is a good point to consider.  I never really suspected it would be
     noticable.

     Cheers!

     Lou Heavner - barking like a dog in Austin, TX, but trying not to be
     dogmatic...

     ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

     >Date: Fri, 21 Apr 2000 16:14:09 -0400
     >From: "Stephen Alexander" <steve-alexander at worldnet.att.net>
     >Subject: temps/more ...
     >
     >Lou Heavner sez ...
     >>   you must always take into account the amount of heat your mash
     >tun
     >>   will absorb. Typically, this will only be 1 or 2 degrees
     >fahrenheit,
     >>    but will vary from system to system.
     >
     >Using the word "must" makes you dogmatic on this forum Lou.  I agree
     >tho',and add that the it's more like 5F if you are making 5g batches
     >in a
     >cellar cool sanke.  Of course as a resident librarian I should point
     >out
     >that heat of malt hydration is also a measurable factor at the HB
     >level.


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Date: 24 Apr 2000 16:58:02 -0400
From: RCAYOT at solutia.com
Subject: Pump Questions

     To all of those who recently wrote about their experience with pumps, 
     I thank you.  I am in the process of taking some or all of my current 
     brewery and building a rack to put it on so I don't have to lift hot 
     wort.
     
     I have decided that I do not necessarily want to be able to apply heat 
     directly to may mash tun, I will use my 10g Gott cooler.  What I do 
     want however is to be able to pump boiling water infusions from the 
     hot liquor tank to the mash tun for temp boosts.  Is there a good pump 
     for ~$125 or less that can actually pump boiling water/wort?  I know 
     that really boiling will be impossible, but close enough so that if I 
     boil water in my HLT can I really pump it quickly to the mash tun?  I 
     need to pump about 2-3g of boiling water in <5 minutes?
     
     For the last tempo boost, or mash out, I usually run 1-3g of sweet 
     wort from the mash tun into the kettle, boil it and return it to the 
     mash tun.  This has worked well many times before, but I suspect that 
     at times it has led to starch haze.  
     
     For those who have a problem with pumping hot wort, may I suggest 
     something I saw my brewing buddy do last time he brewed- He drew the 
     wort through his counter-flow wort chiller and into the fermenter, 
     thus only chilled wort went through the pump!  It would have quite a 
     restriction on the inlet rather than the outlet, but since the wort is 
     cool, and very well de-gassed, it did not appear to cavitate, and went 
     rather quickly.
     
     I am really looking forward to being able to brew 10-12.5g batches 
     without having to lift!
     
     Roger Ayotte



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