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	FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
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Contents:
  Dr. Cone Responds - Al Korzonas - Yeast Density ("Rob Moline")
  Exploding CO2 Tanks, Really? ("Rob Moline")
  Dr. Cone, 2003 - Metabolism  (follow up) ("Fredrik")
  Dr. Cone, 2003 - Aerobic yeast starters (Fred Johnson)
  Practical starter setup? (Jeremy Bergsman)
  Dr. Cone - Attenuation ("Dave")
  Dr. Cone Respomds - Organic and Engineered Yeast - Alexandre Enkerli ("Rob Moline")
  Carbonation in the keg ("Jason Evans")
  Dr. Cone Responds - increasing cell density - Eric Dahlberg ("Rob Moline")
  Potatoes / Beet Sugar / Aneurysms (nlkanous)
  re: autolysis smells ("-S")
  Dr.C.Cone ("-S")
  re: Mash Step Time  and Mash pH & Aerobic yeast propagation ("-S")
  Malt Rice Beer ("Colton House")


* * * * * * * * * * * * * * * * * * * * * * * * * * * * *
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* * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* * * * * * * *       IN  PROGRESS!       * * * * * * * *
*          Dr. Clayton Cone Fortnight of Yeast          *
*      8/11/03 - 8/22/03 Yeast Questions Answered       *
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Date: Fri, 15 Aug 2003 22:42:42 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dr. Cone Responds - Al Korzonas - Yeast Density

			Dr. Cone Responds - Al Korzonas - Yeast Density

Dr. Cone--
   I've read somewhere (but cannot find it anymore) that yeast will
multiply until they reach a certain density (cells/ml) or exhaust
their supply of sterols, whichever comes first.
   But, then I've also read that sterol-deficient yeast (presumably from
underoxygenation at pitching time, right?) will have weak cell
membranes, ultimately resulting in low alcohol tolerance and high
Final Gravities.
   These two seem to be contradictory.  Which is correct?
   Thanks.
   (Can you tell I've been saving up these questions for quite some
time?  This is the last one for now, I think.  Thanks again!)
Al.

Al.
   Sterol, fatty acids, lipids can act as a growth factor. They keep the
cell
wall elastic and fluid allowing transport systems into and out of the cell
to operate. When there is a deficiency during the growth phase the yeast can
not bud, the cell wall is too leathery for the bud to form.  When there is a
deficiency later in the fermentation, the cell wall is no longer fluid and
the transport systems do not allow sugar into the cell and alcohol to move
out of the cell. Alcohol builds up to the point that it becomes toxic. The
cell eventually dies unless it receives oxygen to produce more lipids.
   Yeast will usually continue to multiply until they have exhausted their
nutrient supply: sugar, minerals, vitamins, nitrogen etc. or until they stop
because they have produced a high enough level of their waste product
(alcohol) that it becomes toxic. The toxic effect of the alcohol begins
almost as soon as the alcohol production begins.  The toxic effect is only
very slight in the beginning but becomes very noticeable as the it reaches
5%. There is limited growth after the fermentation reaches 5% alcohol. The
yeast still produce alcohol for cell maintenance.
   In the commercial production of yeast, cell density becomes a factor even
though the yeast is healthy.  The cell population becomes so great that no
know oxygenating equipment can supply enough oxygen to keep the cells
multiplying.

Clayton Cone
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Date: Sat, 16 Aug 2003 00:32:39 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Exploding CO2 Tanks, Really?

From: Michael Hartsock <xd_haze at yahoo.com>
Subject: RE: Exploding CO2 Tanks, Really?
   The CO2 tanks are not capable of exploding.  Explosion
is not the danger; propulsion is the danger.  If
damage is caused to the valve stem of the tank, you
risk having a 1000+ psi steel or aluminum rocket fired
in an unpredictable direction.  Those things can go
through cinder block walls.  This is not an urban
myth, it can and does happen.
   I add another warning: don't pick up or drag your tank
by the valve.
Michael
Columbia, MO


     I can add a further caveat...be sure your tanks are tested/inpected as
required....damage to valves is not the only area of concern.
     Doubters can be referred to Free State in Lawrence, KS., who suffered
through the negligence of their gas/tank supplier to maintain standards. A
steel tank had corroded through the bottom, and indeed became a hazard
through it's subsequent propulsion through several layers of
ceiling/flooring above the tank storage area.
     Happily, this occurred during off-hours, when no one was present.

Cheers!
Gump

"The More I Know About Beer, The More I Realize I Need To Know More About
Beer!"
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Date: Sat, 16 Aug 2003 09:55:52 +0200
From: "Fredrik" <carlsbergerensis at hotmail.com>
Subject: Dr. Cone, 2003 - Metabolism  (follow up)

Dear Dr.Cone and Tobias!

Thank you very very much for answering all the questions!! :) :) Your
answers gave me some very valuable ideas how I need to revise and extend my
thinking on these topics!

I sure hope I am not beeing rude by asking too many questions considering
the limited bandwidth!? But If there is still space left at the end of this
two week period , I do have a couple of follow up questions.

(Lage phase and glycogen)
1) If there is basically no matebolic activity during the lag phase - is the
glycogen level not an issue during the lag phase? I had the impression that
low glycogen levels (like in stored yeast?) would cause an extended lag due
to some "free energy limitation"? I thought that until yeast start to uptake
and metabolise sugars, glycogen (and some others) was the energy supply for
whatever activites that is going on at this time? It this wrong? Are all the
adaptations in the lag phase of passive nature, like equalizing gradients?
requiring no metabolic energy to be spent? I understand that choice of
strain may impact the lag time, but for any given strain, what would be the
most important factors and variables be that determines the length of the
lag?

(sugar utilization)
2) From your answer about sugar utilization, to make sure I got it right,
did I understand things correct if I think there is no regulation of sucrose
uptake and invertase activity due to external glucose? so they would both
start at the same time and go on in parallell? If, as like I would guess(?)
that glucose uptake is alot quicker than sucrose uptake, would it be
possible to observe a small dip in CO2 production activity at the point
where the external glucose is consumed or reached soem treshold? I did
observer such a dip in a test I did. It sure is possible that ambient
conditions cause this, but in this case for some reason I think not, and the
dip coincidently occured at about 6% depletion of fermentables. I would like
to ask you about your opinon if you think that detecting such a dip (about
1.5 hours long and the "dip" was lowering the CO2 rate by some 15%) is
possible? Or do you think I should rule this explanation out and start
looking for another explanation of the dip?

 /Fredrik


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Date: Sat, 16 Aug 2003 10:01:20 -0400
From: Fred Johnson <FLJohnson at portbridge.com>
Subject: Dr. Cone, 2003 - Aerobic yeast starters

Dr. Cone,

Some of us (or perhaps only I) are attempting to culture our yeast 
starters in a respiratory state (with high oxygen and low glucose 
concentrations). In my experience, I cannot deliver very much air to 
the spinner culture using an aeration stone without creating too much 
foam. I have made several beers with poor head retention when I've 
included FermCap in the starter in sufficient quantity to prevent 
foaming in the aerated starter, so I've tried another method that does 
not require FermCap. I have been pumping filtered air at 2 
liters/minute into the head space of a spinner culture with vigorous 
stirring.

Questions:
1. Can pumping air into the head space with vigorous stirring provide 
sufficient oxygen to the yeast to maintain them in a respiratory state 
during incremental infusion feeding?
2. Can FermCap be used in aerated starters without detrimental effects 
on the beer?

Fred L Johnson
Apex, North Carolina, USA



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Date: Sat, 16 Aug 2003 10:02:19 -0400
From: Jeremy Bergsman <jeremy at bergsman.org>
Subject: Practical starter setup?

Martin Brungard posts the following ideas about yeast starters:

> for a starter, you want continuous aeration.  My simple
> oxygen regulator doesn't allow me to meter out really low continuous flows,
> so my oxygen system is no good for continuous use. 
 
> But it appears that incremental feeding is a
> little more important with a malt wort since the glucose level is higher.
> That means I've got to come up with some sort of sterile drip system to
> continuously feed

I have built a (nonbrewing-related) device for other applications which
might serve both purposes.  Given a certain total volume of wort that you
would like to feed to your starter, take a sealable container with several
times this volume, place the wort in it and fill it with O2 at, say, 15
PSI*.  Give it a good shake.  This is now a pressurized resevoir which can
supply oxygenated wort on demand.  You could control the output with a pinch
valve on "rubber" tubing or with an electronically controlled solenoid
valve.

The main question is whether this is enough oxygen.  Wort saturated with
this much O2 is considered more than sufficient for brewing, but I'm not
sure if it would be ideal for starters.

An easy way to build such a device is with PVC plumbing parts.  The Lid
should be a ball valve, for filling with solution.  The Body is some pipe,
maybe 1", held vertically.  The Bottom should adapt down to a hose barb for
taking off the solution during use.  And somewhere on the side you need a
gas inlet.  This could actually be done through the tube on the Bottom, but
you would need to think about how to seal it (the pinch valve might be
sufficient).  You can use a T or tap a hole inthe Side, depending on how you
want to hook up your O2.

If you are making an extra larger starter it would be easy to refill during
the process.

* Rule of thumb (not totally accurate): to get a full dispense the pressure
must be >15PSI/(container volume/wort volume).  PVC is good to much higher
than 15PSI, but I would probably try to limit the pressure to something in
this range for safety issues since a gas-pressurized pipe explosion is more
dangerous than a liquid-pressurized pipe explosion.  As long as the wort is
less than half the volume it should dispense at 15 PSI.
- -- 
Jeremy Bergsman
jeremy at bergsman.org
http://www.bergsman.org/jeremy


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Date: Sat, 16 Aug 2003 14:23:41 -0700
From: "Dave" <brewingisloving at hotmail.com>
Subject: Dr. Cone - Attenuation

Dr. Cone,

I have a situation where I switched from bottled spring water to tap water
filtered through the 10" carbon filter, found at http://www.morebeer.com/
(FIL32), and my beer's attenuation has suffered, seemingly, because of the
change.  My attenuation levels for identical recipes went from 1.013 -
1.015 to 1.018-1.019.

Increasing the amount of aeration and/or oxygenation at the start has no
effect on the FG.  Is there maybe a third cause I am overlooking, or can
filtering water through a carbon filter change the water chemistry enough
to alter the amount yeast attenuates the wort.

Thanks for any information you can provide,

Dave


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Date: Sat, 16 Aug 2003 19:26:50 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dr. Cone Respomds - Organic and Engineered Yeast - Alexandre Enkerli

			Dr. Cone 2003 - Organic and Engineered Yeast - Alexandre

Dr. Cone,
   [Don't want to ask too many questions, and this one is really a matter
of curiosity...]
   Noticed on the label for Wolaver's brown ale that 98% of the yeast was
organic while 2% wasn't. Thinking about your comment on ADN markup, I
was wondering if genetic engineering of brewer's yeast might be a
significant field of yeast development.
   Again, thank you.
Alex, in Montreal


Alex,
   First, I am curious what the 2% non organic would be.
   A significant amount of genetic engineering is being done on all
industrial
yeast: pharmaceutical, distilling, wine, beer etc. At the moment it remains
mostly an academic endeavor (except for the pharmaceutical industry)
because a significant amount of the public is against it. Some fusion work
is been done. This is a type of breeding that is acceptable to the public.

Clayton Cone

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Date: Sat, 16 Aug 2003 21:07:09 -0400
From: "Jason Evans" <brew4me at charter.net>
Subject: Carbonation in the keg

I just gathered all the nessecary components to start 
kegging my lovely homebrew, but I am unsure how to 
carbonate it. Am I able to use the CO2 and pressureize it, 
or must I use DME? Any help in this area would be 
appreciated.
   Jason
   brew4me at charter.net


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Date: Sat, 16 Aug 2003 23:08:19 -0500
From: "Rob Moline" <jethrogump at mchsi.com>
Subject: Dr. Cone Responds - increasing cell density - Eric Dahlberg

			Dr. Cone Responds - increasing cell density - Eric Dahlberg

Dr. Cone, Thank you for your valuable assistance to our homebrewing
community.
   I was hoping you could recommend ways of rapidly increasing cell density
in slow growing yeasts like Brettanomyces. What little I have read about
them mentions that they exhibit a negative Pasteur effect. How should I
alter typical starter procedures for this unique species?
Eric Dahlberg
Rochester, NY


Eric,
   I have very little experience with the non spore-forming Brettanomyces or
the spore forming Dekkera except for the laboratory technique of
identification a Brett infection in beer and wine.  I know that
Brettanomyces requires glucose and lots of oxygen. A regular wort with 3%
glycerol and a magnet stirrer for aeration should be satisfactory.  Brett
produces acetic acid.  This could become a growth limited factor, so it
would be worth while 2% calcium carbonate in the media to neutralize the
acid as it is being produced.
   We have ten or more strains of Brett in our culture collection.  There is
a
vast difference in the growth rate of each. Some grow a 100 fold faster that
others. You may be interested in contacting Dr. Ken Fugelsang, professor in
the Enology department, Cal. State University, Fresno, Ca.  559 209 278
2791.  Ken has done a lot of research on growth rate of Brett, primarily
regarding the wine industry.
   I am curious why are you interested in a procedure for rapidly increasing
the cell density of Brett?  Lambic beer?

Clayton Cone
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Date: Sun, 17 Aug 2003 09:28:42 -0400
From: nlkanous at netscape.net
Subject: Potatoes / Beet Sugar / Aneurysms

Morning,
Dan Morey posts his results of making potato beer and Jeff Renner wasn't 
terribly impressed with the potato beer he tried.  Dan goes on to post
recipes and suggests that his potato beer was much "silkier" in mouthfeel,
as I recall.

One thing to keep in mind about potatoes is that some are waxy and some 
are starchy.  I'll bet Jeff knows this.  Dan reported good results with 
red potatoes.  If I recall correctly, these are waxy potatoes and I would
expect them to add a "silkiness" to the beer as they have a sort of silky
texture themselves.  He also mentions his Yukon Gold that didn't do as 
well in competition.  I don't recall whether this is waxy or starchy but
I'd guess starchy.  The old Idaho Russett potato would be a classic starchy
potato.  Anyhow....not all potatoes are the same.

As for beet sugar processing.....clean or dirty in the end I can tell you 
that Bay City Michigan simply stinks when they're refining sugar beets.  

Regarding aneurysms and beer / lifestyle, keep in mind that this is not a
medical forum.  The information you get here will not always be medically
sound (although some of us have strong medical backgrounds).  The answers
you seek are far more complicated than anyone can easily provide and are
not simply the result of one or the other factor.

My condolences on the loss of a family member for whatever reason.

nathan in madison, wi...home of the Great Taste of the Midwest



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Date: Sun, 17 Aug 2003 18:08:28 -0400
From: "-S" <-s at adelphia.net>
Subject: re: autolysis smells

Wyeast's Dave Logsdon via the Gumpster posts ...

>Regarding other possible sources you inquired about, autolysis
>typically can be better described as sulphery, and dirty diaper.
>[not burnt rubber or scorched plastic.] 

Jethro - would you pass on my special thanks to Dave
Logsdon.

I've been knocking heads on this forum for several years stating
that autolysis NO WAY NO HOW smells like burnt rubber.
That description is an error from some old HB books and like
a pernicious infection it's tough to stamp out this silly
mis-information.

DaveL's insight that phenolics may be the culprit with this type
smell is an inspired thought.  Medicinal, burnt circuit board and
solventy-plastic  are all in line with certain phenolics. Sulphery
& dirty diaper and  brothy, sometimes rancidity are autolysis
signs.  Quite different.

The first SURE sign of autolysis is a not-so-great background
bitterness flavor.  Not a prominent flaw - but a clear one.

 -S(teve Alexander)




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Date: Sun, 17 Aug 2003 20:21:42 -0400
From: "-S" <-s at adelphia.net>
Subject: Dr.C.Cone

Great thanks for considering my questions Dr.Cone.

Many HBDers like to store yeast slurries.  Storage under finished beer or
deionized water at refrigeration temperatures is common.   Some homebrewers
reuse these stored slurries after as much as 60 days of refrigeration !   I
have very grave concerns about the vitality and viability after such long
storage and think that 30 days storage is pushing the envelope.

1 - What is an acceptable  figure for pitched yeast viability (say by a
haemocytometer + MethylViolet stain count).   Is the commercial target of
90% viability too stringent  for the homebrewing  environment ?

2 - What is the viability of properly rehydrated dried yeast like
Lallemand's ?

3 - Please comment on  the expected vitality and viability of a wet homebrew
slurry stored at refrigeration temperatures for various periods.  Obvious
there is no definite answer to such a general question, but perhaps you can
suggest how long is 'probably OK' ?  How long is 'likely too long' ?

4 - Some yeast vendors package wet yeast in refrigerated 'pitchable' tubes.
Is there any means that they could employ to improve the yeast storage
properties beyond that of a homebrewer's refrigerated slurry?  For example,
does anaerobic handling or phosphate buffers, etc improve 'fridge shelf life
of a wet slurry by a great amount ?.

5 - Does the iodine test (iodine into slurry sample to detect glycogen) have
any comparative value to homebrewers as a quick and dirty test of slurry
vitality ?   [Some sources state brief exposure to O2 will  rapidly deplete
yeast glycogen .]

6 - What are the consequences of pitching low viability slurries given that
sufficient viable cells are pitched ?  If I pitched one unit of 100% viable
slurry versus 3 units of 33% viable slurry what would be the expected
difference in the beer ?   Autolyse of non-viable cells ?  Other ?   Does
racking the beer off trub to a secondary prevent this harm ?

- --
On a different topic ...

Many HBers build up large yeast starters, but they do not wish to dilute
their 5 gallon batch of XYZ-style wort with several quarts of pedestrian
starter wort.    They wish to separate the yeast from the starter wort
before pitching.  Many will allow the starter fermentation to nearly
complete then refrigerate it and allow the yeast to sediment before
decanting and pitching .

7 - Does the <attenuation, refrigeration, sedimentation, separation> process
hold potential harm for the yeast ?  For example is the yeast likely to be
less vital than if pitched directly from a high kreusen starter ?

- --
Yet another direction ...

8 - Is there any significant advantage to *very* short 'lag times' (time
between pitching to first sign of  fermentation - usually CO2 outgassing) ?
Many HBers seem obsessed in reducing lag times from 8 hours to 5.
Personally I doubt it makes much difference so long as the lag period is
reasonably brief.

I know that 8 koans in Cone's fountain is a bit, but hopefully some admit
concise answers.

thanks again,
 -Steve Alexander




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Date: Sun, 17 Aug 2003 21:58:00 -0400
From: "-S" <-s at adelphia.net>
Subject: re: Mash Step Time  and Mash pH & Aerobic yeast propagation

Martin G writes ...

>They only hold a mash step for 10
>minutes before either stepping up or going to the mash out temp.

>He indicated they use a steam heated tun and they could do temperature
>increases of about 1C per minute.  He did report that they still have a
long
>runoff time of about 90 minutes.  The surprising thing was that they report
>88 percent efficiency with their mashing process.

I'm not shocked but this efficiency sound a little on the high side.  I'd
expect more like 80% than 88%.

Remember that *if* they do a simple single infusion rest or 10min  at  55C then
a full 1C/min step to mashout at 77C they already have  a 32 minute mash
period plus the MO rest.  You really have to count that slow 1C/minute slide
time as part of the mash period.  The mashout rest will vent about as much
extract from the grist as is possible given the hydration period and the
amylase will happily reduce it at MO temps.    They obviously use a very
well modified malt for this to get 88%.

==========

>Fred's source indicates that molasses is a better
>feed stock for the yeast in that it keeps the glucose level low.

I think that's a misreading.   Any simple sugar can induce Crabtree but the
levels where this happens are quite different for different sugars.
Molasses is cane sugar residue and contains primarily sucrose, quickly
inverted to equal amount of fructose and glucose - each of which can induce
Crabtree effect.  Wort OTOH has only a modest amount of glucose (~6%) and
fructose and sucrose with a majority of the carbs as maltose and lesser amts
of maltotriose.  The maltose & -triose have higher Crabtree thresholds.
Molasses is not superior by reason of preventing Crabtree at given level I
think.  Fred ?

The difficult w/ wort as an aerobic  growth medium is that the yeast have to
shift gears from glucose to maltose to maltotriose and then back again when
the next dosing comes.  That's a lot of metabolic, 'permease' shifting and
schedule of doses is critical to performance.  Mannose and ethanol are other
perfectly acceptable aerobic media - but you need nutrients and amino acids
etc.

>Low glucose
>keeps the yeast from making alcohol, creating cell mass instead.

Not exactly.   Low levels of all the various simple sugars ALLOWS, but does
not require the yeast to respire rather than ferment.   Too much sugar
forces yeast to ferment despite the presence of oxygen.  Yeast build yeast
mass on either energy diet.  They steal a little of the carbon for their
organics chemistry and they oxidize the rest for energy.   The huge
difference is that aerobic oxidation yields something like 18 times the
energy of fermentation.


>All of this information really firms up some changes that I need to
>implement.  I think they may be useful for others to ponder.
>
>1.  Oxygen definitely has its place in my brewing procedures.  [...]
>  But for a starter, you want continuous aeration.

That's not necessarily so.   Yeast will use oxygen when it's available
during growth for UFAs and after squalene precursors are formed in the case
of sterols.   You could probably hit yeast starters with O2 once a day and
get the same sterol and UFA content as for continuous oxygenation or
aeration.    What Fred is doing (and I've toyed with it) is radically
different - he is causing the yeast to respire rather than ferment.   That
does require continuous O2 supply, and low concentrations of glucose *and*
other simple sugars.  The amount of energy available this way is vast *BUT*
the amount of nutrients per unit of wort or molasses is still the same.
You'll run out of amino acids and biotin and niacinimide and a hundred
others before you run out of respirable carbon energy.    Basically
respiration  makes the energy cheap but the relative nutrient:energy ratio
very low - which is a problem.

>2.  I prefer dry malt extract for my starters since it stores well.  I know
>it has the proper nutrients.  But it appears that incremental feeding is a
>little more important with a malt wort since the glucose level is higher.
>That means I've got to come up with some sort of sterile drip system to
>continuously feed

Well really you need to change the drip rate to match the exponential yeast
growth rate without missing the mark by too much or else you'll starve them
or induce crabtree.   By the time your done exploring this in detail you'll
need a lab fermenter which can monitor CO2 and ethanol levels automatically
and dose sugar accordingly.   You might (and Fred probably has) read up on
what they do for yeast growth and harvesting on molasses media (common
practice for bread yeast).   My hunch is that they grow the yeast in aerated
molasses till some nutrient growth limit kicks-in, then the separate the
yeast despite the fact that there is sugar but insufficient nutrient
remaining.

I think what Fred is playing with is great and terribly interesting stuff
but I'm not sure where this takes us in practice.   If you use W amount of
malt extract you have the energy via fermentation to produce X amount of
yeast.   By inducing respiration you have the energy to produce 18X amount
of yeast *but* you only have amino acids for maybe 2X amount of yeast and
*maybe* some of the other  nutrients are even at lower levels.   It's
impractical to buy and add the full set of yeast nutrients - cheaper to buy
malt extract or molasses.

So maybe you get 2X the amount of yeast (well aerated and sterol-full and
ready for pitching) for the trouble of forcing respiration and carefully
dose feeding the batch.

Does that sound about right Fred ?

 -S(teve Alexander)







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Date: Sun, 17 Aug 2003 17:55:57 -0600
From: "Colton House" <coltonhse at btl.net>
Subject: Malt Rice Beer

I was searching the HBD and internet for a recipe using Pearl Barley and
found this recipe for Malt Rice Beer from Vision Brewing.

2 kilos of pearl barley
400 grams of Malt Rice [Koji Rice]
4 grams 9% alpha hop pellets
1 pkt ale yeast
10 litres water

The recipe goes on to explain how to cook the barley and convert it with the
malt rice. Not having access to Koji rice and wanting to experiment with
pearl barley I brewed the following 1 gallon brew last week.

1 lb pearl barley
1 lb medium grain rice
1 lb 2 row malted barley
1/2 oz northern brewer hop pellets  at  7.7%
1 tsp amylase enzyme
1/4 tsp irish moss
1/2 pkt muntons ale yeast

1.    Crushed barley and rice and boiled in 1 gall water for half hour.
2.    Added cold water to cool to 138 degrees added 1 tsp amylase enzyme and
let stand overnight.
3.    Iodine check for conversion then added 1 lb crushed malt and had to
add 2 tsp calcium carbonate to bring to 5.2PH. Then raised temp to 158
degrees for 30 min.
4.    Mashed out at 168 degrees and sparged.
5.    Boiled for 90 min with one hop addition at 30 min and irish moss at 75
min.
6.    Strained and chilled 1 gall beer with O.G. of 1.060.
7.     Presently fermenting in fridge at 65 degrees.

My question is - has anybody tried mashing with amylase enzymes. My
understanding is that it makes a very dry beer and that is why I added some
malted barley to give a bit of body. My second question is - has anybody got
a recipe using pearl barley.

Alan Colton
Swamp Water Brewery of Belize



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