"RogerD" > wrote in message
news:XysZg.27764$P7.9565@edtnps89...
> Hi;
> I have been able to aquire 300 lb of, 2 tons/acre,Yakima, Cab Franc.
> This is the first time I've been able to get this quality of fruit.
> Looks like it may be a bit more ripe than ideal as the TA is low.
> I need suggestions for the best method of adjusting ...
> Tartaric acid or some tart, Yakima, Syrah ???
> Ben ???
>
> SG 1.104
> pH 3.66
> TA 4.0 (freshy calibrated Hanna - juice adjusted to pH 8.2)
> At least they are balanced - low acid / hi pH (my frozen Syrah was hi
pH
> / hiTA)
>
> What would you suggest I adjust to:
> Adjust pH to 3.5 without concern for TA ?
> Adjust TA to 6.0 without concern for pH ?
> Other ?
> (My thought is to adjust TA to 6.0 - with pH ending somewhere below 3.5)
???
>
> Adjust with tartaric acid ?
> Adjust with tart wine ? I have 19 litres of tart Yakima Syrah from
> Spagnol's frozen grape sale:
> pH 3.56
> TA 8.0
>
> Thanks in advance
>
> Roger in the RAinForest
>

Roger,

Potassium bitartrate precipitation during fermentation and MLF reduce the TA
and change the pH. Succinic acid and acetic acid are produced by the yeast
during fermentation and both increase the TA. Sometimes one effect just
cancels the other effect. But, that doesn't happen very often so
calculated values for acid additions are seldom realized.

I would adjust TA and ignore pH. I would add 1.5 grams of tartaric acid per
liter of expected wine (85 liters) before starting the fermentation. A
second small acid addition might be needed after the fermentations are
finished. Adding a little more acid is easy, but reducing acid is much more
difficult.

Be sure to taste the wine after the fermentations are complete. Don't just
go by the numbers.

Good luck,
Lum
Del Mar, California, USA
www.geocities.com/lumeisenman