Interesting suggestion. I'll need to go back through my recent past
winemaking notes to determine if the primary assumption (that "all of the
free SO2 has blown off in fermentation") holds true in my own experience. To
my recollection there is usually some significant free SO2 remaining after
primary. Maybe not enough to invalidate your suggested recipe approach
though.

The problem, of course, with all these 'recipe' approaches is that the
underlying premise is that all wines are more or less equal and that all
winemaking situations more or less the same. I don't find that to be true.
To my mind the only way to control the winemaking process is to have
reasonably empirical information on which to base winemaking decisions.
Biggest improvement in my own winemaking life was this year when I moved
from Ripper to A-O for SO2 measurement. Once you get the hang of it, the A-O
methodology is pretty straightforward (certainly easier than Ripper) and
fun.

I guess for those making small lots on an infrequent basis the investment of
$ and time is not worth it and a more programmatic approach is the easiest
and most efficient. But if the goal is to make 'quality' wine on a
consistent basis then knowing SO2 levels and making informed decisions is
critical, MHO.




> Going with the Keep it Simple process, what about this for and approach
> for those without a chemistry background or a lot of hardware who want
> to use titrettes?
>
> *Ferment the wine and measure the SO2 at completion.
> *Assume whatever your are reading is a false positive value because all
> of the free SO2 should have been blown off in fermentation.
> * Subtract that value from any subsequent reading and maintain sulfite
> levels based on this extrapolated value.
>
> Example:
> Post fermentation reading = 22 PPM.
> Wine is racked and 50 PPM is added
> The next rack 42 PPM is measured.
> 42-22 =20 PPM remaining.
> Measure the pH and determine how much SO2 is needed to protect the
> wine.
>
> I'm not saying it's a precise process but I do think either Lum or Ben
> Rotter proposed that a while back and it's intriguing.
>
> As to the 0.8 molecular; it's a more precise way to discuss sulfite
> levels in wine. The general value of 50 PPM is based on maintaining
> 0.8 molecular at a pH of 3.6.
>
> I can post a chart of pH vs recommended PPM sulfite from Margalit but I
> think it's already in the FAQ.
>
> Joe
>
> Lum Eisenman wrote:
>> "Ric" > wrote in message
>> ...
>> > Lum - do you think .8 ppm molecular SO2 is necessarily required? Some
>> > literature suggests a range between .5 and .8; I've been tending
>> > towards
>> the
>> > lower end of that range in a desire to use as little KMS as possible.
>> Could
>> > be dumb luck, but thus far (only two seasons at those lower levels,
>> > admittedly) no issues.
>> >
>> > thoughts?
>> >
>> Ric,
>> I don't think 0.8 PPM is a magic number. Down here in the southwest, pH
>> levels tend to be high so many winemakers try and maintain 0.8 PPM for
>> white
>> wines and 0.5 PPM for red wines. After all, it is possible to make good
>> wine without using any SO2. But, the wine wont last very long and the
>> winemaker had better keep things very clean.
>> Lum
>> Del Mar, California, USA
>> www.geocities.com/lumeisenman
>