I don't have a SO2 tester but what is the typical SO2
level after adding a kit's potassium metabisulfite?

The kit had slowed right down to a bubble every minute
of two and when I check it a few weeks later it had
stopped. Being somewhat close to an bonehead I assumed
fermentation was done and added the potassium meta. Now
I realize it was stuck at 1.010. I've tried adding yeast
nutrient, using EC-1118 and a warming belt to heat it
up to 70F, and a splash racking. No luck. I forget the
exact numbers but Philip Jackisch book recommends adding
0.7 ml of 3% H2O2 to lower it (I think) 20 ppm. In any
case, I need to know the ballpark level right now.

It's a Pinot Gris Kendall Ridge kit. Is there another
possibility for the stuck fermentation?

Don

Don,

My two best sources on this question are Lum Eisenman and Ben Rotter.
You can find some good information on this question at Ben Rotter's
site: http://members.tripod.com/~BRotter/

Firstly to clarify, your comment on the dosage of H202 from Jackisch
that "0.7 ml of 3% H2O2 to lower it (I think) 20 ppm" should be
expressed with the quantity being treated in this case I believe it is 1
gal. Also, when I try to verify the calculation it appears he is
referring to 0.7 ml lowering 1 gal by only 10 ppm's. When using H202
you need to be very careful on the dosage. I believe he refers to 1 gal
that I assume is a U.S. gal (3.785 liters) and not an Imperial Gallon.

According to my calculations .18 ml (actually .17556 ml) of 3% H202
lowers 1 liter of wine by 10 ppm's free SO2. Again, I think you should
check through your own calculations but I am quite confident of these
numbers.

The bottom line is:
- Each .18 ml of 3% H2O2 will lower 1 liter by 10 mg/l free SO2.
- Testing the SO2 level before and after H2O2 addition is advised.
- H2O2 should be added slowly.
- There is a limit in the amount of SO2 that can be added as the
reaction at low levels produces insignificant amounts of H2SO4 (sulfuric
acid) but if too much is added a bitter taste will appear in the wine.

You can use the level I cited above to check the Jackisch dose although
I expect they are quite close.

Good luck,


Glen Duff
-----------

Don S wrote:

> I don't have a SO2 tester but what is the typical SO2
> level after adding a kit's potassium metabisulfite?
>
> The kit had slowed right down to a bubble every minute
> of two and when I check it a few weeks later it had
> stopped. Being somewhat close to an bonehead I assumed
> fermentation was done and added the potassium meta. Now
> I realize it was stuck at 1.010. I've tried adding yeast
> nutrient, using EC-1118 and a warming belt to heat it
> up to 70F, and a splash racking. No luck. I forget the
> exact numbers but Philip Jackisch book recommends adding
> 0.7 ml of 3% H2O2 to lower it (I think) 20 ppm. In any
> case, I need to know the ballpark level right now.
>
> It's a Pinot Gris Kendall Ridge kit. Is there another
> possibility for the stuck fermentation?
>
> Don
>

Glen,
Your right in that it was per gallon I forgot to put that
in although I was thinking it (half points). I will check the
20 ppm vs 10 ppm when I get home but your probably right I
was working from memory and should have stated that. It's
actually better to see your calculation in ml/l that cancels
out the need to figure out gallons. Anyway I will double
check everything but....

- do you know the general SO2 level in a kit, real ball park
because I don't think I need to bring it down too far. The
EC-1118 should have good SO2 tolerance. Maybe I'll just bring
it down 10 ppm at a time and give it a small EC-1118 dosage
after each.

- Does H2O2 degrade? I have some but it could be year old.
Actually I think I will buy new stock but it would be good
to know anyhow.

Don

> Firstly to clarify, your comment on the dosage of H202 from Jackisch
> that "0.7 ml of 3% H2O2 to lower it (I think) 20 ppm" should be
> expressed with the quantity being treated in this case I believe it is 1
> gal. Also, when I try to verify the calculation it appears he is
> referring to 0.7 ml lowering 1 gal by only 10 ppm's. When using H202
> you need to be very careful on the dosage. I believe he refers to 1 gal
> that I assume is a U.S. gal (3.785 liters) and not an Imperial Gallon.
>
> According to my calculations .18 ml (actually .17556 ml) of 3% H202
> lowers 1 liter of wine by 10 ppm's free SO2. Again, I think you should
> check through your own calculations but I am quite confident of these
> numbers.
>
> The bottom line is:
> - Each .18 ml of 3% H2O2 will lower 1 liter by 10 mg/l free SO2.
> - Testing the SO2 level before and after H2O2 addition is advised.
> - H2O2 should be added slowly.
> - There is a limit in the amount of SO2 that can be added as the
> reaction at low levels produces insignificant amounts of H2SO4 (sulfuric
> acid) but if too much is added a bitter taste will appear in the wine.
>
> You can use the level I cited above to check the Jackisch dose although
> I expect they are quite close.
>
> Good luck,
>
>
> Glen Duff
> -----------
>
> Don S wrote:
>
> > I don't have a SO2 tester but what is the typical SO2
> > level after adding a kit's potassium metabisulfite?
> >
> > The kit had slowed right down to a bubble every minute
> > of two and when I check it a few weeks later it had
> > stopped. Being somewhat close to an bonehead I assumed
> > fermentation was done and added the potassium meta. Now
> > I realize it was stuck at 1.010. I've tried adding yeast
> > nutrient, using EC-1118 and a warming belt to heat it
> > up to 70F, and a splash racking. No luck. I forget the
> > exact numbers but Philip Jackisch book recommends adding
> > 0.7 ml of 3% H2O2 to lower it (I think) 20 ppm. In any
> > case, I need to know the ballpark level right now.
> >
> > It's a Pinot Gris Kendall Ridge kit. Is there another
> > possibility for the stuck fermentation?
> >
> > Don
> >

Jackisch did list it as a 10 ppm decrease in SO2 by
adding 0.7 ml of 3% H2O2 per gallon of wine. Assuming
a US gallon I think.

Still wondering about the probable SO2 level in a
finished kit wine. If I remember correctly I've seen
the potassium meta package being listed as a 5 gm
package. From Jack Keller's page:

Potassium metabisulfite, 1 gram = 150 ppm in 1 gallon,
30 ppm in 5 gallons

That would make it 150 ppm since I split this kit out
into a 19l carboy and some 750/375 ml bottles for
topping up.

Don

Don,

If I were you I'd pick up a SO2 titrate kit (Ripper method). The cost
is not prohibitive although the vials are around 2.50 to 3.00 Canadian
per test. The test is simple to do and can be done in a few minutes. I
would highly recommend this.

Test the level and let us know. If you're at 150 ppm's you're probably
near the upper limit for treating with H2O2 but I think you have a
chance. However, a much better alternative is to half the SO2 level by
buying another kit and blending. If you need to treat with H2O2 it
would require less dosage. Personally I'd consider that possibility as
well - a little extra wine never hurt anyone.

Let us know of your next steps, I have empathy for you as I did the same
thing last year to two large batches of beautiful Gewurztraminer and
Riesling juice. I was in a hurry and did not double check my dosage. I
reduced the SO2 level by blending with additional juice, lowering with
H2O2 and waiting for the best part of a year as the SO2 decreased. I
did try a little splashing. The wine is okay but not nearly as good as
it should have been.

Cheers,

Glen Duff
------------

Don S wrote:

> Jackisch did list it as a 10 ppm decrease in SO2 by
> adding 0.7 ml of 3% H2O2 per gallon of wine. Assuming
> a US gallon I think.
>
> Still wondering about the probable SO2 level in a
> finished kit wine. If I remember correctly I've seen
> the potassium meta package being listed as a 5 gm
> package. From Jack Keller's page:
>
> Potassium metabisulfite, 1 gram = 150 ppm in 1 gallon,
> 30 ppm in 5 gallons
>
> That would make it 150 ppm since I split this kit out
> into a 19l carboy and some 750/375 ml bottles for
> topping up.
>
> Don
>

Glen,
Thanks for all of the information, I appreciate it. The SO2
tester is in the plans as well but no one seems to sell one
in Ottawa. Is this the item:

http://shop.piwine.com/shopsite/prwc/product578.html

As I mentioned before I tried splashing. I've already bought
the lowest end kit I could find to try doubling up but thought
I might do the H2O2 method prior to it. I think what I will
try over the holidays is another splash racking and a light
H2O2. If that does not work I will double up.

Did you switch to EC-1118 or a comparable yeast when you had
your problem?

Don

>
> If I were you I'd pick up a SO2 titrate kit (Ripper method). The cost
> is not prohibitive although the vials are around 2.50 to 3.00 Canadian
> per test. The test is simple to do and can be done in a few minutes. I
> would highly recommend this.
>
> Test the level and let us know. If you're at 150 ppm's you're probably
> near the upper limit for treating with H2O2 but I think you have a
> chance. However, a much better alternative is to half the SO2 level by
> buying another kit and blending. If you need to treat with H2O2 it
> would require less dosage. Personally I'd consider that possibility as
> well - a little extra wine never hurt anyone.
>
> Let us know of your next steps, I have empathy for you as I did the same
> thing last year to two large batches of beautiful Gewurztraminer and
> Riesling juice. I was in a hurry and did not double check my dosage. I
> reduced the SO2 level by blending with additional juice, lowering with
> H2O2 and waiting for the best part of a year as the SO2 decreased. I
> did try a little splashing. The wine is okay but not nearly as good as
> it should have been.
>
>