The final SG of a wine fermented to dryness has to account for the fact
that the alcohol in the wine is less dense than water. That's why the
dry wine has an SG less than 1.000. A wine at SG 1.000 is not quite dry.

Gene

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.
>
> 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 -
>