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Contents:
  Re: Responses to my Stainless Steel parts question ("Rob Dewhirst")
  re. Galv pipe and flocculation value ("zuvaruvi")
  March fitting (Bjoern.Thegeby)
  Electric Brewery ("richard")
  Wyeast #2278 (HOMEBRE973)
  Hops for Irish Red ("Christian Rausch")
  Lagering Schedule ("Paul Niebergall")
  South Africa (Jeff Renner)
  Re: Electric Brewery ("Paul Clarke")
  Galvanized pipe and gas ("Mike Sharp")
  Re: Attempt#2 Explianing idea on "Energy balance" / sugar residuals ("Fredrik")
  Short overview over model lineout ("Fredrik")
  Re: Electric Brewery ("Doug Moyer")


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Date: Mon, 18 Oct 2004 21:44:29 -0500
From: "Rob Dewhirst" <rob at hairydogbrewery.com>
Subject: Re: Responses to my Stainless Steel parts question


> However, it appears that nobody McMaster-Carr included) sells the part
> I was looking for: a stainless steel fitting with a 1/2" female NPT
> end for attaching to the input or output of a March pump, and a hose
> barb (either 1/2" or 3/8") on the other end.
>
> My thought now is to get a 1/2" male NPT x 3/8" hose barb fitting, and
> adapt it to the pump using a stainless coupling that's female 1/2" NPT
> on each end.  Anyone else done this, or have any other
> thoughts/suggestions?

The "fitting" you are looking for is indeed two parts.

You want two 1/2" SS NPT couplers, and two nylon or polysulfone($) 1/2" 
NPT->barb adapters, one for each threaded side of the pump housing.

Lots of people have done this. 



Return to table of contents


Date: Mon, 18 Oct 2004 21:11:27 -0700
From: "zuvaruvi" <zuvaruvi at cox.net>
Subject: re. Galv pipe and flocculation value

Kent says:

>and the building inspector will make you do it all
>over again in black pipe.

Galv, black, green...it's all that heavy steel stuff (insert Tim Allen 
grunting ape noises).  Yes, black pipe, of course; thank you for saving me 
from a fate worse than permit payment.

Steve asks:

>Now if someone would explain the survival value of yeast flocculation to 
>me,
>please. Where's the sense in non-sexual cells calling a 'huddle' at the
>start of dormancy? Brewer & vintner's appreciate this property but
>couldn't have influenced it (much).

Just talking out my wazoo here..  First, we're looking at the wrong media, 
wort, must....  Show me wort in nature; you're not going to find it. 
Secondly, weather yeast colonize and sink (sacch), or colonize and float 
(brett), is largely a function of cell density (specific gravity) and 
(incidental) ability to entrain co2 (ale vs. lager) and the number of buds 
in a chain....  (And I realize flocculation and colonization are two 
different mechanisms but bear with me here).  Flocculation merely describes 
what we observe occurring in an artificial medium, wort.  But, regardless of 
weather it floats or sinks, "sticking together" provides obvious natural 
benefits with regard to survival: trapped intercellular nutrient, residual 
moisture, co-existing with non-predatory partners..  And when you take into 
account these mechanisms are occurring in drops of sap, in grapes that have 
been penetrated by insects, in apricots that have fallen to the ground and 
ruptured.colonization is a perfectly sensible strategy.  I think 
flocculation in wort is merely incidental to natural colonization 
mechanisms; an assertion I can make as long as yeast philosophy seams to be 
prevailing over yeast physiology....

Now you can argue that after 5000 years of brewing, wort has affected 
natural selection of yeast sp.  I won't argue one way or the other.  But 
having five gallons of 18-22% nutrient/ 7% alcohol wort floating overhead 
seems a far more hospitable environment than a 0% nutrient/ 8.4% alcohol 
environment.

Is yeast at the bottom of a vat of beer truly dormant?  Were they truly 
dormant, autolysis wouldn't occur.  Allowing a certain percentage of slowly 
metabolized nutrient to remain in solution makes perfect sense with regard 
to longevity if yeast are never completely dormant while in liquid.  I'm a 
yeast rancher; I've kept about 20 different strains viable under beer for a 
year or more at a time.  True dormancy may only occur in dry environments.

Being in the company of true yeast greatness for the next fortnight, I'm 
sure to be corrected swiftly and surely if my wazoo is too far askew.

FWIW,

Chad Stevens
QUAFF
San Diego 



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Date: Tue, 19 Oct 2004 08:45:18 +0200
From: Bjoern.Thegeby at cec.eu.int
Subject: March fitting

Benjy asked:

"However, it appears that nobody McMaster-Carr included) sells the part 
I was looking for: a stainless steel fitting with a 1/2" female NPT end 
for attaching to the input or output of a March pump, and a hose barb 
(either 1/2" or 3/8") on the other end"

How about this at www.morebeer.com

"H618B: Stainless- 1/2'' FPT x 1/2'' Barb" 

Cheers
Bjorn Thegeby
Rennerian, schmennerian, five miles from Lembeek.



Return to table of contents


Date: Tue, 19 Oct 2004 21:34:20 +1000
From: "richard" <richard_beattie at optusnet.com.au>
Subject: Electric Brewery

Many thanks for the posts and personal emails. It has given me a fair bit
of information to think about.

	I've installed a 2200W (240V) kettle element, (pulled out of a cheap kettle
bought at a department store for under $10), in a plastic bucket for the
HLT. No problems here with scorching as you can't scorch water - so this is
fine and working well. I'll post some pics on the web at some stage. Kettle
elements are very easy to mount in the plastic buckets as they come ready
with a good "bulkhead" fitting. For those in OZ I bought them from Big W.
"Belle" brand. (link to the actual element tech info - this is an
interesting web site. I never realised that there are counterfeit kettle
elements !!???:  http://www.strix.com/product/t72_data.htm )

	(bucket was polypropylene, rather than HDPE - any thoughts on the use of
polypropylene - anyone?? It was a cheap bucket at the local hardware store -
but did say "Food Contact Approved" on the label. It was also a bit thin at
about 1.9mm - so I bought two and am using one inside the other to beef up
the strength. I may take the opportunity of adding a layer of aluminium foil
between the two buckets to give a bit of insulation)

	Now onto the kettle..

	The posts and emails sent in were fairly mixed. Some people are using 2200W
or 2400W elements with no issues. Some have had dramas and suggest going
straight to gas. Reading back through the early posts on this subject, the
critical factor seems to be power per surface area of the element - with a
"safe" zone proposed to be about 50 - 83 watts / square inch, (refer to Ken
Schartz and C.D Pritchard's excellent posts in the archives plus their web
sites - many thanks !!). My element is about 5/16 inch diameter and about 20
inches long - so surface area (I think) is 5/16 x 3.1416 (PI) x 20 = say 19
square inches, (maths aint my strong point). At 2200W the power per square
inch is 115, which is well over the safety zone. (my maths maybe wrong. I
reviewed a few similar equations on the web and could not understand the
maths for this. Am I missing something or it this logic correct.??)

	However - there seems to be a lot of people using similar kettle elements
with no issue. Most look pretty similar in terms of surface area. One
example is Dave Pickett:

	http://www.users.zetnet.co.uk/dpickett/docs/brewery/boiler.htm

	who actually has two in his kettle. So is it really an issue?? My options
at this point:

	1/  Install one element in the kettle and run at the full 2200W and see
what happens. Maybe I can do a trial run by dissolving some sugar in water
and boiling it up. Any scorching or scorched taste should be evident after
an hour boil. (????)
	2/  Use a diode to bring the voltage back to about 170V - which will
roughly halve the wattage of the elements and run them at 1100W. I can then
install 2 elements for a total of 2200W. I'm not that good at "electricity"
so am not too keen on this sort of tinkering.
	3/  Install two elements in series - but this means each element will only
run at 550W so I'm halving the power in the kettle. (another quick thought -
at only A$10 an element it maybe an idea to install 4 elements (2 x 2 in
series) and run each at only 550W - but with 4 you still get 2200W in the
kettle. Also has the advantage of being able to switch off one of the
circuits thus having an easy way to half power for some control. 4 elements
maybe a little crowded - but it also has the advantage of spreading the heat
out nicely as well.
	4/  See if I can find a cheap kettle with a 1200W element (or thereabouts)
and install two of these.
	5/  Forget about an element approach for the kettle and buy a couple of SS
pots and do a split boil on the stove. When I bought the cheap kettles I
noticed that the same department store was selling19 litre thin walled SS
pots with a glass lid for A$19. So this maybe an option to get going.

Thanks again all for assistance. I'll send through a link when I post some
pics.

Cheers- Richard.





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Date: Tue, 19 Oct 2004 08:59:47 -0400
From: HOMEBRE973 at aol.com
Subject: Wyeast #2278

I have just made a Pilsener with Wyeast#2278.  It
is now finishing its ferment at 50 F. before lagering.
I was wondering if anyone has tried to use this
yeast in an ale fermented around 60 to 70 degrees
F.?  While the Pilsener is lagering, I was hoping
to make a quicker style British ALe--is using this
yeast feasible for the task?
Thanks
Andy from Hillsborough, NC


Return to table of contents


Date: Tue, 19 Oct 2004 09:30:54 -0400
From: "Christian Rausch" <brewmaster at rauschbiercompany.com>
Subject: Hops for Irish Red

Hello everyone.

I am planning on brewing this weekend. I want to make an Irish red ale.
Thing is I am out of Fuggles. I was going to use Willemette, but was not
sure if this hop is the right substitute. Does anyone have any experience
with this?  I am out of Kent Goldings as well. Maybe I should just say the
heck with it and brew a Bock. Ideas welcome.

Cheers,

Christian Rausch
www.rauschbiercompany.com





Return to table of contents


Date: Tue, 19 Oct 2004 08:51:09 -0500
From: "Paul Niebergall" <pnieb at burnsmcd.com>
Subject: Lagering Schedule

Hello, 

I bought a temperature controller for my extra fridge and am planning
my first lager (Oktoberfest) this weekend.  (Figured I would finally
take the plunge after 18 years of brewing ales.).

Anyway I have been searching the web for a good lagering
time/temperature schedule, but everything I have found seems pretty
vague.  Can anyone out there recommend or point me in the direction of a
decent lagering schedule??

BTW - I am using an Oktoberfest Yeast.  I cant remember right now if it
was Wyeast or White Labs, but it came in a sodapop blank (test tube) and
was labeled "Oktoberfest".  The manufacture date was July 2004, the
starter has been in the fridge for 2 days at 47 to 52 degrees F, and I
am seeing some pretty decent activity in the airlock.  Roused and fed it
some fresh wort this morning.

Also I think I got the 47 to 52 degree F range from Noonan (BLB - 1986)
, but the label says to brew at like 55 to 60 degrees.  Isnt that kind
of warm?  Should I bump up the starter temp to increase activity?  It
seems to being doing well were it is at.

TIA, 

Paul Niebergall
Stilwell Kansas



Return to table of contents


Date: Tue, 19 Oct 2004 10:47:00 -0400
From: Jeff Renner <jeffrenner at comcast.net>
Subject: South Africa

Brewers

Did you all feel the giant lurch in the Homebrewing Universe 
coordinates?  [0,0] Rennerian shifted precisely 8486 miles to the SE 
from 4 to 15 Oct.  It was a wonderful trip, and the brewers in 
Johannesburg took me at my word when I asked to be sent home tired. 
They showed me a wonderful time in their beautiful country.

Since arriving home Friday I've been trying to catch up on sleep and 
email, with little avail.  We leave Thursday for a week in California 
for our daughter's college graduation (Hooray!!!), so it will only 
get worse, so a complete report will have to wait.

Until then, a big thanks to the Wort Hog Brewers of Johannesburg, and 
especially Ant Hayes and Llew van Rensburg, for their wonderful 
hospitality.  And congratulations to the nine brewers who sat the 
first BJCP exam to be given outside North America.  I'm sure they did 
their club proud.

Cheers

Jeff
- -- 
Jeff Renner in Ann Arbor, Michigan USA, JeffRenner at comcast.net
"One never knows, do one?"  Fats Waller, American Musician, 1904-1943


Return to table of contents


Date: Tue, 19 Oct 2004 11:12:44 -0400
From: "Paul Clarke" <ptclarke at sympatico.ca>
Subject: Re: Electric Brewery

Pete Calinski - I can't take credit for that web page.  The owner's name is
Alan McKay ( www.bodensatz.com ).  Alan is kind enough to supply space
and tools to allow his registered members to post pictures and albums on his
site.

As for my pilot lamps, if I had been smart enough to originally purchase
GFCI units with the lamps built in, I wouldn't have had to buy these little
things.  I was actually looking for a couple of night lights when I stumbled
across them.

Jody  - While these heating elements are rated at wattages above 1250, you
will find that most household dimmer switches are rated at less than half
that
number. So right off the top, I would say no, don't use one for this job.

Dimmer switches are designed to dissipate heat when under load.  If you have
one in the house, touch it's cover plate after it has been on for several
minutes.
You may be surprised at how warm it is.  I'm afraid that a load of 1250+
watts would cause so much heat to be generated, you would risk at least a
melt down if not a fire.

It's possible that there are industrial models that can handle much higher
loads, but I haven't looked around for any and can't imagine what the price
might be.  I think you would be better off trying Pete's stove top burner
idea, but you may have to do some "mcgyvering" to make it fit the electical
box.  I'm sure Pete can help you out with that.

As I said in my earlier post, I haven't found a need to do this yet.  You
only
really need to hover over it and cycle the switch until after the first boil
over
threat has passed.  After that everything settles down to a nice rolling
boil
and you don't have to be so dilligent.

Paul




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Date: Tue, 19 Oct 2004 08:49:51 -0700
From: "Mike Sharp" <rdcpro at hotmail.com>
Subject: Galvanized pipe and gas

Kent Fletcher correctly points out that galvanized pipe can't be used
for natural gas.   

A very good point--good catch!  And I'm sure that's true where Chad
lives.  

In the past I've used PVC coated black pipe for gas installations where
corrosion might be a problem.  It's rated for gas (uncoated on the
inside)  and there is a black PVC tape that can be used at the joints
and where a pipe wrench messes up the coating.  

Regards,
Mike Sharp


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Date: Tue, 19 Oct 2004 18:42:29 +0200
From: "Fredrik" <carlsbergerensis at hotmail.com>
Subject: Re: Attempt#2 Explianing idea on "Energy balance" / sugar residuals

> Hmmm. You were the one who was trying to explain this 
> fermentation model based  on "energy". I just commented
> that your energy approach was not valid from a 

There is alot more to it too. I had the impression that you 
suggested I start out by listing the kinetics for every single 
molecule in a cell. Perhaps it's a misunderstanding again. 
Anyway, I've received some of the initial comments I wanted 
on this particular part.Thanks Dave.

> You need to take floccuation into account in any model of 
> fermentation.  The flocculated yeast are still alive just not in 
> the field of action where the fermentable wort is.  Stirring 
> flocculated yeast  does allow them to come into contact with
> wort with residual  fermentable sugars by moving this solution 
> past the yeast and the attentuation % rises over the non-stirred 
> one.

I agree with the effect. 
My preferred theory is that removing CO2 and gradients reduces
the stress, making the cells come *back out of dormancy*. Ate
end of fermentation I think there may be some slight circulation
here. High flocculation may favour the dormancy in this circulation

I had planned to account at least partly for flocculation, I like to 
think of it as a defence mechanism (sticking together and decrease
the surface area to a hostile and toxic environment). 
It's just the way I like to think of it 
until I know better, this may be wrong. "Facts" are annoying to 
me :) I rather have some crazy working hypothesis that I at least 
can prove wrong. Just makes me feel better than live with a fact
and have not explanation. The question is exactly what triggers it, 
I am leaning toward the same triggering as dormancy?? One way 
I can realize flocculation as "cause rather than an effect" is that a 
cell can go dormant, and then go back online later, if conditions
fluctuate, due to oscillation in pressure or inhomogen mixtures.
At that point it is the rate of transitions from dormancy to active 
state may be slower if the cells already flocculated alot. So the 
point where the cells are borderline to favaouring dormancy, 
maybe a high flocculation tendency may 
turn this balancing into a quicker ending, by pulling it over the 
edge. This is what I would expect in a simulation of this. I 
haven't found much other info on this so far. 

I am currently assuming that only dormant cell flocculate. Does 
anyone think this is an incorrect assumption? Any good 
explanations why an active cell would flocculate? I might see
some less compelling, but I wonder?
 
> Basically, I would look at it as though the  forces which separate 
> the yeast  bodies are no longer effective at keeping them apart.

Sounds like think modelling surface molecule states for triggering
will be difficult. Perhaps initiation of dormancy will provide more 
managable triggering giving the similar output? If one can find
the "reason" for the flocculation, that might be easier to model than
the acual molecular mechanism that executes it. I realized already
that I can not attempt to model everything from the molecular 
mechanism level. I have to try and model the mechanism that
relate to flavour compounds though. That would be complex 
and probably fairly chaotic. I am trying to make the model as 
general as possible, but I have to keep the complexity down as 
much as possible or it will not be practical.

 /Fredrik





Return to table of contents


Date: Tue, 19 Oct 2004 18:44:42 +0200
From: "Fredrik" <carlsbergerensis at hotmail.com>
Subject: Short overview over model lineout

(2nd try, do I have email problems?)
After discussing details, fwiw, to put it into context 
here is a short overview of the model (so far) I am 
working on...

I divided the variables, and parameters into 
three parts (that interact). The point is 
that I want the parametrization of the wort,
yeast strain, and fermentor to be independent.
For example, the specific growth rate 
obviously depends on the wort composition 
and alot of other things, therefore the 
growth rate would not be a parameter intrisic 
to the yeast strain, and a bad chose of
parametrization. Most model I have see so 
far (I've seen a few at least) fail in two ways.
First the model only a subset of all interesting
variables. Second they are often parametrized
in a way that makes little sense. Parameters
that depend both on sugar composition, and
on the yeast strain, and on ambient conditions.

I am using a complete *functional approach*. 
(I am not considering linking any dynamics to 
a specific gene, because I am not modelling
the actual DNA and transcription stuff 
anyway, that's just way out of scope.
That said these insights can still be useful 
and provide hints during the process.) I 
try to model how the fermentation dynamics 
works, and find a suitable decomposed 
parametrization. 

The model is intended for realistic batch 
fermentations as used by homebrewers like
myself and should be able to handle 
variations in ambient conditions like air 
pressure and temperature.

1) Yeast
  This further decomposes the cells into 
  three states
  - Active
  - Dormant
  - Dead

  I am modelling this as 3 variables. 
  # of active cells
  # of dormant cells
  # of dead cells

  Assumptions
  - Only Active cells reproduce
  - Only active cells significantly consume 
    external sugars
  - Only dormant cells flocculate
 
  The transitions between all the states are 
  treated on a statistical basis. This is 
  where some of the energy analogies apply. 
  
  active <-> dormant
  active -> dead
  dormant -> dead

  All cells are not in the sames state all 
  the time, at some point 5% may be dead, 
  80% active, 15% dormant etc. Therefor not 
  only wort sugar concentrations is of 
  importance, the health and age of the 
  individuals matter too. And I attempt to
  solve this my considering transition 
  probabilites which hopefully will account
  for the distribution. Unhealthy and damaged 
  individuals will go dormant first, while
  the more healthy ones stay active longer.
  Therefore I will have to model some yeast 
  variables like UFA, sterols in all 3 states
  also by carrying over these values during
  transitions. This is a simplification that 
  I hope will be roughly ok.

  Furthermore I have assigned variables that 
  may be recognized as these *health related* 
  yeast variables
  - UFA
  - Sterols 
  - Glycogen
  - Trehalose
  - Cell energy balance ("ATP levels") 
  - Also perhaps Cell redox balance 
    (I've implemented it, but it remains to see 
     what use I will have for it)

  About the carobhydrate pathways I am still 
  expanding it, but as a starter it would look 
  something like this:

http://hem.bredband.net/frerad/beer/modelling/pictures/pathways.jpg

  (many parts are missing above, but to come)

  I fear the nitrogen pathways will be a real pain 
  in  the butt :-| so I decided to leave that for 
  a little later. In the "first round" I just 
  consider then basic nitrogen demand, as a single 
  variable "FAN" but this will not do for a final 
  version.

  I've learnt alot of the basic pathways from the
  http://www.yeastgenome.org/ which is an excellent 
  site.

2) Wort/Beer
   - Wort composition, sugars, nutritions (eventually 
     amino acids), O2 and CO2 levels
   - EtOH, esters, diacetyl, etc

   The sugar profile and maybe amino acid profile 
   would require a mashing modell. Which would be 
   another project. I started making some lineouts 
   on that I it doesn't look too hairy, at least 
   not worse than the fermentation model. I think 
   some of the hardest parts may be distribution 
   phenomena in the liquification process. Acconting 
   for stirring and crush, rehydration etc, is 
   probably a significant part of modeling the mash. 
   The only existing model I've found relates to 
   simulating starch breakdown some stuff relating 
   to rice. There was a quite interesting algoritm 
   that takes care of the recursive probability 
   evaluations for enzyme targets at various bonds 
   in the starch molecule. If someone wants it 
   perhaps I can looks for the reference. 

3) Fermentor/Ambient conditions
   - This deals with stirring, heat exchange 
     dynamics through the fermentor walls and 
     an ambient temperature (that can vary), 
     headspace pressures vs ambient athmospheric
     pressure that can also vary. Dyanmics of the 
     CO2 supersaturation, production, and gas 
     flow out of fermentor. Fermentor geometry.

   One of the things I will be able to measure is CO2 
   flow. I will correlate the model with actual CO2 
   flows eventually.

So to explain what I aim at. As this is quite 
complex, and considering I am no biologist nor 
biochemist I must remember that I do not intend 
to come up with a full blown model that 
can model the cell purvate levels to within 1%
or the actual ATP levels at any time. Neither 
do I intend to model the internal cell organells
and machinery itself. That is a much harder 
task, that I leave for someone else to do. 
All I want is, using this functional appraoch 
to model the beer fermentation, and the basic 
yeast responses as relevant for brewing. Using 
some reasonable simplifications based on insights 
how yeast are likely to work. Once the model is 
in place, it will need alot of training the model
against data, to tune all parameters, also 
some of the regulation function might be changed 
as a result of training.

The reason I invent a variable that I relate 
to ATP for example, is that it "symbolises" the 
energy state of the cell, kind of like the 
ATP-ADP-AMP balance. But of course it makes 
little sense for me to pinpoint these things to 
an absolute level as I will never measure the
ATP level in a cell. For me, it's basically a 
mathematical exploit, that does have a real
counterpart, but the linking is soft, and not
hard.

The first step is to organize all this into parts
of the equations and leave place for future 
changes. The typical "constants" are implemented 
as state functions, where the case of an actual 
constant would be the most trivial case.

There are many details yet to work out. But
I don't want to start hardcoding details until 
I've got the right structure in place, and I'm 
still working on the structure. This is why I 
haven't posted any equations yet. The math
is only a tool and I don't want to post 
formulas to obscure the discussions of interesting
concepts. Once the concept and principles are
clear the equations will pop out themselves. 
But I will be back with more details when I 
have had time to do more work.

 /Fredrik



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Date: Tue, 19 Oct 2004 20:31:18 -0400
From: "Doug Moyer" <shyzaboy at yahoo.com>
Subject: Re: Electric Brewery

Jodie asks about using a dimmer switch to control a water heater element.

Be careful with this option, as the dimmer switches go up dramatically
(exponentially!) in price as you increase power. You'd be better off having
two elements operating at less than 10 amps, each with its own dimmer vs.
going for a 15 amp or 20 amp dimmer. Of course, then you have more assembly
work, but you're using a cheap resistive dimmer vs. an expensive SCR
dimmer...

Brew on!



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