jim wrote:

Heh sorry to miss you out. Thanks for the info.

I understand that PA starts with the potential.
What I am getting at is that SG and PA are given
a common correlation as being discussed in
this thread. Yet, SG works on total movement
(from initial to final
SG). So, what is the difference between a wine
with PA of 15 that finishes at SG 1.000 and a
wine with a PA of 15 which finishes at 0.990?

That still *weirds me out* Many thanks and I
hope this isn't too off topic.

Ray Calvert had a discussion on this point about a
year ago with another poster. I don't think it
was ever resolved.

In my calculations I use formulae that were
developed by UC Davis. Of course, this does not
mean that they are bullet proof.

In order to resolve this, I think someone (who
actually cares enough - or is interested enough)
to actually do an experiment and ferment a wine
with a known initial SG and a final SG (both
corrected for temperature - preferably with a
high initial SG and a very low final SG) and send
the finished wine to a certified lab for results
of PA. The test is not all that expensive,
especially considering all the controversy about
the topic.




Jim

On Nov 27, 1:04 am, pp
wrote:
Why is everybody calling me Joe these days? :-p

As for the 0.990 vs 1.000 difference,
basically, you can think about it as the table
being designed so that instead of using the
difference between the starting and final sg
points, you're only using the starting point.
In other words, the table is built with the
assumption that your wine ferments completely
to dryness (because that's what PA means) and
gives you the PA values with that assumption.

Pp

On Nov 26, 1:37 pm, jim
wrote:

I use this

table:http://www.brsquared.org/wine/CalcInfo/HydSugAl.htm
which backs paul and joe's comments.

I have to admit though, I never quite
understood how this can be if 0PA is 1.000
and I usually ferment down to around 0.990

Jim

On Nov 26, 8:36 pm, pp
wrote:

On Nov 26, 11:46 am, "Paul E. Lehmann"
wrote:

Joe Sallustio wrote:

Hi. Is there a special starter I
should use to
re-start this? Room temperature
shouldn't be an issue - it's being
kept in my pantry so it is always warm
enough.

Steve's post already gave you great
advice and the correct value of
'potential alcohol' for 1.100SG. (My
tables came from NBS so I know
they are right.) The only thing I
would expand on is the amount of
time to give it to get going. Starters
need to get going really well
before you add them to the total
volume. I keep doubling the volume of
the starter and let it get back to
fermenting strongly.

13% ABV for an apple wine might be a
little heavy duty; if this died at
around 9 or 10 % I
might be happy with that. I show that
as 1.022 to 1.029 S.G.

bobdrob,
I show 1.115 as 19.3 % ABV; I have the
book at home that probably
takes them higher; I have spreadsheet I
made on
my work PC. I can email you the
spreadsheet.

Joe

Joe, are you sure of that? I quick check
on my program shows 1.115 SG to be
equivalent to 15.78 Brix and the PA to be
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Same here - don't have the tables on me but
last couple of years we got some Zin and
Petite Sirah grapes that were over 1.130. I
remember checking the PA on those and even
that was definitely under 20% - not that we
fermented them that way!

Pp- Hide quoted text -

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