"Lum" > wrote in message >...
>
> Hi Pp,
> You may not have a measurement error. Acid adjusted, grape fermentations
> often measure from 0.5 to 1.5 g/l higher after fermentation because yeast
> produces succinic acid during fermentation. If you chill the wine to 32
> degrees or so for a few days, potassium bitartrate will precipitate out of
> the wine and reduce the titratable acid. Sometimes, the drop in TA due to
> tartrate precipitation is about equal to the increase in from succinic acid,
> and the TA of the cold stabilized wine ends up being just about equal to the
> starting TA. See Margalit, Concepts in Wine Chemistry, page 17.
> lum

Hi Lum:

Thanks a lot for this interesting info. I've always thought the acid
level is supposed to drop after fermentation by about 0.5g/L on avg.
So, if I understand this correctly, after cold fermentation, the acid
can actually move in any direction w.r.t to the starting level,
depending on the levels of succinic acid generated and bitartrate
falling out? And, does this only apply to juice that has had tartaric
acid added to it or in general?

I'll definitely check out the Margalit reference, only have to hunt it
down, which will take some time.

Thx,

Pp