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
>> > > > 15.78- Hide quoted text -
>>
>> > > > - Show quoted text -
>>
>> > > 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 -
>>
>> > - Show quoted text -