SO2, MLF, and Pinot Noir

SO2, MLF, and Pinot Noir

Post by Dan Emers » Wed, 12 Dec 2001 01:41:11



I have a Pinot Noir finishing MLF, cool at about 60 degrees.  I see a
bubble every couple of minutes.  Stirring the lees every week. The pH
was about 3.48 measured about a week ago.

I am wondering about SO2.  Should I measure the total SO2 and try to
keep the free SO2 to some minimum level?  I don't want to lose this
one, tastes pretty good so far.

Dan

 
 
 

SO2, MLF, and Pinot Noir

Post by Tom » Wed, 12 Dec 2001 01:46:48



Quote:
> I have a Pinot Noir finishing MLF, cool at about 60 degrees.  I see a
> bubble every couple of minutes.  Stirring the lees every week. The pH
> was about 3.48 measured about a week ago.

> I am wondering about SO2.  Should I measure the total SO2 and try to
> keep the free SO2 to some minimum level?  I don't want to lose this
> one, tastes pretty good so far.

You want to adjust the free SO2 to about 40ppm.  If you have not yet
sulfited the must/wine you will need to add in excess of that number because
some of it will immediately disappear into bound forms that are not
available to protect the wine.

Tom S

 
 
 

SO2, MLF, and Pinot Noir

Post by Dan Emers » Wed, 12 Dec 2001 06:38:50


Quote:



> > I have a Pinot Noir finishing MLF, cool at about 60 degrees.  I see a
> > bubble every couple of minutes.  Stirring the lees every week. The pH
> > was about 3.48 measured about a week ago.

> > I am wondering about SO2.  Should I measure the total SO2 and try to
> > keep the free SO2 to some minimum level?  I don't want to lose this
> > one, tastes pretty good so far.

> You want to adjust the free SO2 to about 40ppm.  If you have not yet
> sulfited the must/wine you will need to add in excess of that number because
> some of it will immediately disappear into bound forms that are not
> available to protect the wine.

> Tom S

Thanks Tom,

I sulfited at crush at 1/2 tsp per 100 pounds (I think that is right.
Whatever it is, I checked here first and got the right amount).  Do I
have to monitor it during MLF to maintain a small amount of SO2, or
wait until MLF is done and then rack and sulfite.

Dan

 
 
 

SO2, MLF, and Pinot Noir

Post by Tom » Wed, 12 Dec 2001 14:01:52



Quote:
> I sulfited at crush at 1/2 tsp per 100 pounds (I think that is right.
> Whatever it is, I checked here first and got the right amount).  Do I
> have to monitor it during MLF to maintain a small amount of SO2, or
> wait until MLF is done and then rack and sulfite.

The latter.  Remeasure again in a week or so and adjust if necessary.

Tom S

 
 
 

SO2, MLF, and Pinot Noir

Post by Bruce Matthew » Fri, 14 Dec 2001 13:57:07


I am confused.  I thought MLT was malolactic fermentation and I thought this
took place in ageing, long after racking off the lees.  And don't you
normally sulfite the must right after you crush to kill off the wild yeasts.
And is it necessary to add a malolactic starter and starter food?  I'm
getting this slowly - maybe time to hit the library.....
Thanks for any help here.......
Bruce

Quote:



>> I have a Pinot Noir finishing MLF, cool at about 60 degrees.  I see a
>> bubble every couple of minutes.  Stirring the lees every week. The pH
>> was about 3.48 measured about a week ago.

 
 
 

SO2, MLF, and Pinot Noir

Post by Dan Emers » Sat, 15 Dec 2001 01:11:25


Tom,

I measured the SO2 last night, about 20 - 25 ppm free SO2.  I used a
nice little kit from Chemectrics called Titrets, catalog number
K-9610W.  Works really well.  It apparently measures free SO2.  At
20-25 ppm I think I am probably OK for a while.  Just wait until MLF
is done, a month or so? and rack and sulfite.

Sure tastes good.  Could have waited a little longer for pressing.  I
pressed at a gravity of 1.009 or brix of about 2.  Next year I'll wait
a little longer.

I'm considering barreling but really concerned about over oaking in a
small barrel.  My volume is only 70 liters (18.5 us gallons) so I can
only use a 10 gallon barrel.  A new one would impart too much oak in
only a couple of months storage.  I suppose I could barrel 10 gallons,
then put in the remaining 8 gallons after a couple of months with 2
gallons of the first batch.  Then keep it filled with kit wine until
next years Pinot harvest.

Is it worth it for such small volumes?

Quote:



> > I sulfited at crush at 1/2 tsp per 100 pounds (I think that is right.
> > Whatever it is, I checked here first and got the right amount).  Do I
> > have to monitor it during MLF to maintain a small amount of SO2, or
> > wait until MLF is done and then rack and sulfite.

> The latter.  Remeasure again in a week or so and adjust if necessary.

> Tom S

 
 
 

SO2, MLF, and Pinot Noir

Post by Joe Sallust » Sat, 15 Dec 2001 07:28:51


MLF reduces titratable acid and can enhance mouthfeel, but you have to
let it go to competion if you want to take advantage of it.  It's very
sensitive to SO2 so if you want it to happen, you leave SO2 at a
minimum until it's done.  How do you know it's done?  What you are
doing is converting Malic acid to a weaker lactic acid, so you measure
the amounts of those acids with a paper chromatography setup.

Hope that helps
Regards
Joe

 
 
 

SO2, MLF, and Pinot Noir

Post by Tom » Sat, 15 Dec 2001 10:57:27



Quote:

> I am confused.  I thought MLT was malolactic fermentation and I thought
this
> took place in ageing, long after racking off the lees.

Spontaneous ML tends to occur later in a wine's development.  Modern
winemaking technique is inoculation with a cultured strain, often right at
the beginning of the sugar (yeast) fermentation so they run concurrently.

  And don't you

Quote:
> normally sulfite the must right after you crush to kill off the wild

yeasts.

Yes, but the gassing of the fermentation blows off most of the SO2, so the
ML goes pretty much unimpeded, if delayed a little.  A lot of winemakers add
no SO2 at crush if the grapes look clean and healthy so's to help the ML
along.

Quote:
> And is it necessary to add a malolactic starter and starter food?

Not necessary, but advisable.  Spontaneous bacterial fermentations can
sometimes produce some unpleasant flavors, aromas and excessive levels of VA
(volatile acidity).  Same goes for yeast.  It's cheap insurance.

Tom S

 
 
 

SO2, MLF, and Pinot Noir

Post by Bruce Matthew » Sun, 16 Dec 2001 10:33:10


Many thanks Tom.  I'm learning more from this forum than I ever would from a
text, although Lum Eisenman has a very detailed book on the internet that
you probably know of.  Looks like a good bit of chemistry in good
winemaking....  Haave a good Christmas holiday.

Quote:

>Spontaneous ML tends to occur later in a wine's development.  Modern
>winemaking technique is inoculation with a cultured strain, often right at

 
 
 

SO2, MLF, and Pinot Noir

Post by Tom » Fri, 21 Dec 2001 14:04:19



Quote:
> Tom,

> I measured the SO2 last night, about 20 - 25 ppm free SO2.  I used a
> nice little kit from Chemectrics called Titrets, catalog number
> K-9610W.  Works really well.  It apparently measures free SO2.  At
> 20-25 ppm I think I am probably OK for a while.  Just wait until MLF
> is done, a month or so? and rack and sulfite.

> Sure tastes good.  Could have waited a little longer for pressing.  I
> pressed at a gravity of 1.009 or brix of about 2.  Next year I'll wait
> a little longer.

> I'm considering barreling but really concerned about over oaking in a
> small barrel.  My volume is only 70 liters (18.5 us gallons) so I can
> only use a 10 gallon barrel.  A new one would impart too much oak in
> only a couple of months storage.  I suppose I could barrel 10 gallons,
> then put in the remaining 8 gallons after a couple of months with 2
> gallons of the first batch.  Then keep it filled with kit wine until
> next years Pinot harvest.

> Is it worth it for such small volumes?

AFAIC, _yes_.  I was surprised to learn that the aspect ratio of smaller
barrels isn't that different from standard 60 gallon barrels.  One thing I
might mention:  if you're talking about a new or newish American oak barrel,
I'd recommend that you not put Pinot Noir in it.  Pinot Noir and American
oak aren't a match made in heaven.  Use chips (French) or StaVin "beans"
instead.

If you have a French (or other European) barrel, you should be OK for an
entire year - or at least until next year's crush.

Tom S