Hi Jack,
I follow your logic, but the last column on that table was actually
the difference between points of 5 C, not from maximum density. It's
way too coarse at 5C steps so I started to make one in 1 C steps,
then I decided I had better think this through.

I am actually wondering if any of this is valid since both the
container and must are changing with temperature. I know the general
coefficient of thermal expansion for glass, I may plug that in and run
a few numbers after thinking it through.

Joe



.... The
> CRC tables all begin with the density of water being 1.000 at 4
> degrees C (39.2 F), whereas we all constitute our must and the
> resulting wine at a much higher ambient temperature. Our mixtures
> have already expanded due to elevated temperature and so we begin with
> X liters of wine under airlock at, say, 68 degrees F and then the
> temperature rises. The volumetric expansion from 39.2 F, which your
> table predicts, is meaningless to us. We need the expansion from 68
> F. It turns out one can calculate this from your table, but it isn't
> all that straightforward.
>
> Any idea how to more easily work the problem we face in real life?
>
> Now, having said all of that and asked my question, I still say the
> solution is not to be surprised by a volume increase due to rising
> temperature. Simply look at your carboys daily and when the wine
> approaches the airlock remove the airlock and then some of the wine.
> That is another use of a wine thief.
>
> Jack Keller, The Winemaking Home Page
> http://winemaking.jackkeller.net/