"Wayne Harris" > wrote in message
...
> In my continuing quest to kill this batch of wine, I have messed up
> the acid balance.
>
> Here is the story:
> I have a 5 gallon batch of Cabernet Sauvignon (from concentrate) that
> has finished primary.
> Prior to inoculating, I measured the reconstituted juice and found
> that the titrateable acid was very low, about .3%. I wanted to raise
> the acidity to between .6% and .7%.
> In order to do this, I used the following formula:
>
> 4.1g Tartaric Acid/1 gallon = .1% rise
>
> So in order to raise 5 gallons of wine to .65% (a .35% rise) I
> calculated the following:
>
> 5(4.1g)/5(1) gallon=.1% rise
> 3.5(20.5g/5gal)=3.5(.1%) rise
> 71.75g/5gal=.35% rise
>
> I added this acid to the juice and re-measured the TA. It was up to .
> 4%
> After a 20 min wait, I re-measured and it was still .4%
> I added another 20g.
>
> After a 20 min wait, I re-measured and it was still .45%
> I added another 20g.
>
> After a 20 min wait, I re-measured and it was still .45%
> I then added 40g.
>
> After a 20 min wait, I re-measured and it was still .7%
> good
>
> Now, almost 2 months later, I re-measured and the TA is .82
> Crap
> The taste is very tart. Go figure.
>
> So, what is the best way to add acid? Should I have waited longer
> before adding more? Does it take a while for the acid to fully
> dissolve?
>
> Where did I go wrong?
>
>


(Oct 2003)
Ed Goist once wrote:

«Throughout the fermentation of a grape-based wine, there is both an
increase in the Total Titratable Acidity resulting from fermentation,
and a decrease (precipitation) of some of the grape's natural fruit
acid (Tartaric).

The acids resulting from fermentation & the winemaking process account
for an increase in TA of approximately 2.0 - 2.5 g/l. This increase
is mostly the result of the formation of Succinic acid [0.5-1.25 g/l].
Succinic acid is the "acid of ethanol" & it is responsible for the
common sour taste shared by all alcoholic beverages. However, other
acids are formed as well during the fermentation, including: Lactic
[~0.3 g/l ], Phosphoric, Carbonic (from the formation of CO2),
Sulfurous (due to the pre-fermentation addition of SO2) & Acetic.

However, with a grape wine, this increase in "fermentation related"
acids is almost perfectly offset by an equal reduction in Tartaric
acid due to the precipitation of potassium bitartrate during & after
fermentation.

Note that this same increase in the TA during fermentation also occurs
with wines made from concentrate, as the process of concentration
removes almost all of the potassium bitartrate from the must prior to
fermentation».