Does anyone know the maximum amount of H2O2 that can
be added to wine in order to reduce SO2? I know I need
an SO2 meter but at this point I don't have one and
haven't gotten around to ordering one over the net.

I have 5 gal of a Pinot Gris kit and I accidently added
the potassium meta packet before it was dry. I've splashed
racked 3 times and added 0.7 ml/gal 3% H2O2 on one
occaision and have now added another 1.4 ml/gal with
an addition of EC-1118. No joy. If I'm going to toss
it I might as well go to the limit first. The SO2 has
been lowered by 30 ppm with the above additions and
perhaps another 20 by the splash racking. Another 1.4
ml/gal perhaps?

Don

Anyone?

> Does anyone know the maximum amount of H2O2 that can
> be added to wine in order to reduce SO2? I know I need
> an SO2 meter but at this point I don't have one and
> haven't gotten around to ordering one over the net.
>
> I have 5 gal of a Pinot Gris kit and I accidently added
> the potassium meta packet before it was dry. I've splashed
> racked 3 times and added 0.7 ml/gal 3% H2O2 on one
> occaision and have now added another 1.4 ml/gal with
> an addition of EC-1118. No joy. If I'm going to toss
> it I might as well go to the limit first. The SO2 has
> been lowered by 30 ppm with the above additions and
> perhaps another 20 by the splash racking. Another 1.4
> ml/gal perhaps?
>
> Don

"Don S" > wrote in message
om...
> Anyone?
>
> > Does anyone know the maximum amount of H2O2 that can
> > be added to wine in order to reduce SO2? I know I need
> > an SO2 meter but at this point I don't have one and
> > haven't gotten around to ordering one over the net.
> >
> > I have 5 gal of a Pinot Gris kit and I accidently added
> > the potassium meta packet before it was dry. I've splashed
> > racked 3 times and added 0.7 ml/gal 3% H2O2 on one
> > occaision and have now added another 1.4 ml/gal with
> > an addition of EC-1118. No joy. If I'm going to toss
> > it I might as well go to the limit first. The SO2 has
> > been lowered by 30 ppm with the above additions and
> > perhaps another 20 by the splash racking. Another 1.4
> > ml/gal perhaps?
> >
> > Don

I'm not sure just how to answer your question Don.

In general, H2O2 reacts with SO2 and produces sulfuric acid. Excessive wine
oxidation will occur if more H2O2 is added after all the SO2 is gone.

So, one answer might be.....measure the free SO2 and add enough H2O2 to
oxidize the excess SO2. But, significant amounts of sulfuric acid will be
produced if your wine contains large amounts of SO2, and you may not like
the taste of sulfuric acid.

lum
Del Mar, CA, USA

> I'm not sure just how to answer your question Don.
>
> In general, H2O2 reacts with SO2 and produces sulfuric acid. Excessive wine
> oxidation will occur if more H2O2 is added after all the SO2 is gone.
>
> So, one answer might be.....measure the free SO2 and add enough H2O2 to
> oxidize the excess SO2. But, significant amounts of sulfuric acid will be
> produced if your wine contains large amounts of SO2, and you may not like
> the taste of sulfuric acid.


Lum,
It sounds then like splash racking ispreferable to using H2O2
then. How does SO2 break down in the presence of oxygen?
I think one more dose of 1.7 ml/gal and a splash rack then...
hmmmm, I always end up on that "why toss it" path.

I gotta buy that tester, I gotta buy that tester...

Don

"Don S" > wrote in message
om...
> > I'm not sure just how to answer your question Don.
> >
> > In general, H2O2 reacts with SO2 and produces sulfuric acid. Excessive
wine
> > oxidation will occur if more H2O2 is added after all the SO2 is gone.
> >
> > So, one answer might be.....measure the free SO2 and add enough H2O2 to
> > oxidize the excess SO2. But, significant amounts of sulfuric acid will
be
> > produced if your wine contains large amounts of SO2, and you may not
like
> > the taste of sulfuric acid.
>
>
> Lum,
> It sounds then like splash racking ispreferable to using H2O2
> then. How does SO2 break down in the presence of oxygen?
> I think one more dose of 1.7 ml/gal and a splash rack then...
> hmmmm, I always end up on that "why toss it" path.
>
> I gotta buy that tester, I gotta buy that tester...
>
> Don

Don,

In wine, free SO2 is in three forms: as a dissolved gas (SO2), as bisulfite
(HSO3-) and as sulfite (SO3--). At wine pH, most of the free SO2 is in the
bisulfite form. Splash racking removes SO2 from the wine several ways. (1)
Some of the dissolved SO2 gas comes out of solution and drifts away in the
air. (2) Oxygen is introduced into the wine, and some of the alcohol is
oxidized into acetaldehyde. Bisulfite then reacts with the acetaldehyde and
becomes bound SO2. (3) Some of the sulfite reacts with oxygen and produces
sulfate (sulfuric acid).

I would try (1) another dose of H2O2 plus lots of splashing. (2) Build a
large starter using Prise de Mousse yeast. (3) Add very small quantities of
wine to the starter (1/4 wine, 3/4 starter) until all of the wine is
fermenting.

The renewed fermentation will blow off more SO2 gas and will
reduce much of the acetaldehyde back into alcohol. But, much of the sulfate
will remain in the wine.

Good luck,
lum
Del Mar, CA, USA

Lum,
Last questions (I think), is Prise de Mousse equivilent to
EC-1118? I'm guessing it is or at least a close enough relative
to use here. Doing kits I have alot of 1118 packets around.

Is the idea with the starter to slowly introduce the yeast to
higher and higher quantities of SO2 and I take it if yes then
that is preferable to rehydrating the yeast and adding it the
entire 5 gals.

What can I make the starter out of - would sugar and water,
perhaps inverted sugar be OK?

Don


>
> In wine, free SO2 is in three forms: as a dissolved gas (SO2), as bisulfite
> (HSO3-) and as sulfite (SO3--). At wine pH, most of the free SO2 is in the
> bisulfite form. Splash racking removes SO2 from the wine several ways. (1)
> Some of the dissolved SO2 gas comes out of solution and drifts away in the
> air. (2) Oxygen is introduced into the wine, and some of the alcohol is
> oxidized into acetaldehyde. Bisulfite then reacts with the acetaldehyde and
> becomes bound SO2. (3) Some of the sulfite reacts with oxygen and produces
> sulfate (sulfuric acid).
>
> I would try (1) another dose of H2O2 plus lots of splashing. (2) Build a
> large starter using Prise de Mousse yeast. (3) Add very small quantities of
> wine to the starter (1/4 wine, 3/4 starter) until all of the wine is
> fermenting.
>
> The renewed fermentation will blow off more SO2 gas and will
> reduce much of the acetaldehyde back into alcohol. But, much of the sulfate
> will remain in the wine.
>
> Good luck,
> lum
> Del Mar, CA, USA