I'm a home beer brewer and was just starting to
read up on winemaking and have a question. I have
'a into to winemaking' pamphlet and it explains
the process on how to do a acid test. Where the
acidity is expressed in terms of P.P T or Percent
as Tartaric. It goes on to say that a wine made
from White grape should be between 6.5 - 7.5
P.P.T. Tartaric and Red grape wine 6.0 - 6.5 P.P.T
Tartaric. Are these numbers Ph? If not What is the
difference. The pamphlet does not express anything
about Ph anywhere. Is it important?

Dan
Mt. Clemens, MI

"Dan Rock" > wrote in message
news:msOdnZvrUrvF4JvZnZ2dnUVZ_sCdnZ2d@wideopenwest .com...
> I'm a home beer brewer and was just starting to
> read up on winemaking and have a question. I have
> 'a into to winemaking' pamphlet and it explains
> the process on how to do a acid test. Where the
> acidity is expressed in terms of P.P T or Percent
> as Tartaric. It goes on to say that a wine made
> from White grape should be between 6.5 - 7.5
> P.P.T. Tartaric and Red grape wine 6.0 - 6.5 P.P.T
> Tartaric. Are these numbers Ph? If not What is the
> difference. The pamphlet does not express anything
> about Ph anywhere. Is it important?
>
> Dan
> Mt. Clemens, MI


Dan,

In the United States, titratable acid in wine is expressed in grams of acid
per 100 milliliters of wine, and titratable acid is calculated as if all of
the different acids in the wine were tartaric acid. Please note that 1 gram
of acid in 100 grams of wine is equivelent to 1%. The acid content of most
finished table wine ranges from 0.55 to 0.85 percent. The desirable acid
content depends on style and how much residual sugar is left in the wine.
Grapes grown in cool climates often contain too much acid, and fruit grown
in warm climates may contain to little acid. Adjusting the starting acid
content of the grapes before starting fermentation is one of the more
important winemaking tasks. The goal is to have just enough acid to produce
a balanced wine.

Lum
Del Mar, California, USA

To (briefly) answer your question about pH:

The acid content of wine is expressed as grams per litre or a
percentage--this is what you are talking about with the numbers above.

pH indicates the strength of the acid, not it's concentration/amount.
pH can certainly be important, since higher pH (i.e. less acidic)
results in a greater chance of microbial spoilage--the weaker the acid,
the more likely organisms are going to be able to live in your wine.
It also affects how much sulphite gets bound up and how much is left to
protect your wine.

I suspect that most home winemakers don't measure pH.

I think a simple search of this newsgroup will deliver several threads
about pH if you want to know more.

do yourself a favor and don't even add acid, your wine will come out
smoother and better tasting......that is a French trait.......They don't
even know how to make beer much less wine.....I stopped using acid years ago
and have won many an event and people never tasted any diffenence......it
was just smoother......winner. donny
"Dan Rock" > wrote in message
news:msOdnZvrUrvF4JvZnZ2dnUVZ_sCdnZ2d@wideopenwest .com...
> I'm a home beer brewer and was just starting to
> read up on winemaking and have a question. I have
> 'a into to winemaking' pamphlet and it explains
> the process on how to do a acid test. Where the
> acidity is expressed in terms of P.P T or Percent
> as Tartaric. It goes on to say that a wine made
> from White grape should be between 6.5 - 7.5
> P.P.T. Tartaric and Red grape wine 6.0 - 6.5 P.P.T
> Tartaric. Are these numbers Ph? If not What is the
> difference. The pamphlet does not express anything
> about Ph anywhere. Is it important?
>
> Dan
> Mt. Clemens, MI
>
>

Thanks all for the responses, I know that after I
do some more research I'll have more questions.