"Paul S. Remington" > wrote in message
om...
> "Ray" > wrote:
> <Snip!>
> > The calculation I use is that published by Duncan and Acton in
Progressive
> > Winemaking.
> > PA = (G begining - G ending) / F
> > Where
> > G = 1000 * (SG - 1) = gravity
> > and
> > F = 7.75 - 3*(G begining - 7) / 800
> <Snip!>
>
> Hello Ray, et al.,
>
> I ran my numbers for a Chardonnay in long-term aging to see what PA
> the formula above reports. I must be doing something wrong because
> the answer I'm getting is an impossible PA. Can someone run-through
> how they're determining the answer based on my SG? Either the formula
> is wrong or I'm wrong. Considering what I do for a living, I lean on
> the latter; I'm NOT a mathematician! Rather, I was a Liberal Arts
> major. :-)
>
> Beginning SG: 1.098
> Ending SG: .998
>
> The final alcohol rating I calculated with a hydrometer after
> fermentation completed was 13.75%.
>
> Much appreciated, gentleman!
>
> -Paul

Hi Paul

I'm not a mathematician either, so I will let those guys answer that part
of your post. Hydrometers and "standard" charts haven't changed in
my (long) life time, so I will continue to believe that they are the best
that "science" has been able to come up with (so far).

Here is how I would evaluate your wine:

Your ferment got stuck. You have about 2% residual sugar and your
alcohol is about 12.4%abv. I would not trust this wine to remain
stable in the bottle with this much remaining sugar in it.

I would taste it to confirm the presences of sugar and then test it with
clinitest to try to determine how much. If more than 0.5%RS, I would
stabilize by raising SO2 to not less than 0.83ppm molecular and add
enough sorbate to insure stability.

OTOH - You might decide you want to force it to go dry. To do this
with this much alcohol already present will be troublesome. Use a
very high alcohol tolerant yeast such as P. Cuvee (PdM) etc, and a
slow "doubling" procedure to let the yeast get used to the high
alcohol content. HTH

Frederick