In article
>,
shbailey > wrote:

> On Feb 26, 9:46*am, Wildbilly > wrote:
> > In article >,
> >
> > *BobF > wrote:
> > > Wildbilly wrote:
> >
> > > > How much of what did you add? Malic is more sour than tartaric, for
> > > > example (it drops the pH more than an equivalent amount of tartaric).
> >
> > > malic does NOT reduce pH more than tartaric. *malic will buffer the pH
> > > higher.
> >
> > Added to water, malic will result in a lower pH than tartaric. Any
> > buffered solution will resist a change in pH. Malic only results in a
> > higher pH when it is converted to lactic acid in a secondary
> > fermentation (malolactic).
> > --
> > "Fascism should more properly be called corporatism because it is the
> > merger of state and corporate power." - Benito Mussolini.
> >
> > http://news.yahoo.com/s/ap/20100119/...rrestin...http
> > ://www.democracynow.org/2010/1/19/headlines
>
>
> It is probably time for a review of wine acidity basics with Jack
> Keller
> http://winemaking.jackkeller.net/acid.asp
>
> Converting malic to lactic acid reduces sourness, but tartaric has the
> lowest pH. Any serious discussion about winemaking with the Norton
> grape will involve dealing with high pH at fairly high TA due to the
> high ratio of malic acid.
>
> Jack's article also gives a general answer to jim c's original
> question.
>
> Stephen

Brain FART!

Agreed, I was in error. I was thinking of an article that I read not
long ago, but numbers don't lie.

http://en.wikipedia.org/wiki/Acid_dissociation_constant
Acid dissociation constant
From Wikipedia, the free encyclopedia

Acetic acid, a weak acid, donates a proton (hydrogen ion, highlighted in
green) to water in an equilibrium reaction to give the acetate ion and
the hydronium ion. Red: oxygen, black: carbon, white: hydrogen.
An acid dissociation constant, Ka, (also known as acidity constant, or
acid-ionization constant) is a quantitative measure of the strength of
an acid in solution. It is the equilibrium constant for a chemical
reaction known as dissociation in the context of acid-base reactions.
Where HA is a generic acid that dissociates by splitting into A-, known
as the conjugate base of the acid, and the hydrogen ion or proton, H+,
which, in the case of aqueous solutions, exists as a solvated hydronium
ion. In the example shown in the figure, HA represents acetic acid, and
A? the acetate ion. The chemical species HA, A- and H+ are said to be in
equilibrium when their concentrations do not change with the passing of
time. The dissociation constant (Ka) is usually written as a quotient of
the equilibrium concentrations (in mol/L), denoted by [HA], [A-] and
[H+]:
Ka = [H+] [A-]/ [HA]

Due to the many orders of magnitude spanned by Ka values, a logarithmic
measure of the acid dissociation constant is more commonly used in
practice. pKa, which is equal to -log10*Ka, may also be referred to as
an acid dissociation constant:

The larger the value of pKa, the smaller the extent of dissociation. A
weak acid has a pKa value in the approximate range -2 to 12 in water.
Acids with a pKa value of less than about -2 are said to be strong
acids; a strong acid is almost completely dissociated in aqueous
solution, to the extent that the concentration of the undissociated acid
becomes undetectable. pKa values for strong acids can, however, be
estimated by theoretical means or by extrapolating from measurements in
non-aqueous solvents in which the dissociation constant is smaller, such
as acetonitrile and dimethylsulfoxide.

Malic pKa1 = 3.4, pKa2 = 5.13

Tartaric pKa1 = 3.2, pKa2 = 4.8
--
"Fascism should more properly be called corporatism because it is the
merger of state and corporate power." - Benito Mussolini.

http://news.yahoo.com/s/ap/20100119/...ting_activists
http://www.democracynow.org/2010/1/19/headlines