two questions about MLF
 

For the first season, I've been able to conduct really successful MLFs. I
found that the "trick" was to use the powdered Chris Hansen ML bacteria, use a
healthy dose of ML nutrient, and do it at a 78-80 degree temperature. Now,
after about 6-8 weeks, a ML chromatogram shows no malic acid spots, but there
are still occasional tiny bubbles in the carboy. The wines haven't been
sulfited yet.

Should I expect the bubbles to COMPLETELY stop? I suspect that this won't
happen, and I'm anxious to do a final racking and add some sulfite. So that's
my first question: Do I have to wait for the MLF to COMPLETELY stop? Or will
the sulfite do the job, or should I resort to lysozyme?

Secondly, I have a couple other batches of wine in various stages of their
primary fermentations or completely finished which were never innoculated with
ML and which were sulfited from the beginning. Just for the heck of it, I ran
a chromatogram on those as well and while they have very obvious malic acid
spots, they also have pretty prominent lactic acid spots. Does this mean that
I have incomplete ML fermentations on those, or does lactic acid occur
naturally?

Thanks, as always.

Lee

"LG1111" > wrote in message
...
> For the first season, I've been able to conduct really successful MLFs. I
> found that the "trick" was to use the powdered Chris Hansen ML bacteria,
> use a
> healthy dose of ML nutrient, and do it at a 78-80 degree temperature.
> Now,
> after about 6-8 weeks, a ML chromatogram shows no malic acid spots, but
> there
> are still occasional tiny bubbles in the carboy. The wines haven't been
> sulfited yet.
>
> Should I expect the bubbles to COMPLETELY stop? I suspect that this won't
> happen, and I'm anxious to do a final racking and add some sulfite. So
> that's
> my first question: Do I have to wait for the MLF to COMPLETELY stop?

When my wines get to that point, I hit it with SO2, top up and bung tight.
If your wine is in a carboy, be careful about that last part though. Bung
it too tight and a temperature shift can blow the bottom out of the carboy.

> Secondly, I have a couple other batches of wine in various stages of their
> primary fermentations or completely finished which were never innoculated
> with
> ML and which were sulfited from the beginning. Just for the heck of it, I
> ran
> a chromatogram on those as well and while they have very obvious malic
> acid
> spots, they also have pretty prominent lactic acid spots. Does this mean
> that
> I have incomplete ML fermentations on those, or does lactic acid occur
> naturally?

That's a very good question that I can partially answer. I suspect that you
have spontaneous ML going on in that wine - especially if the pH is above
3.5.

Tom S

"LG1111" > wrote in message
...
> For the first season, I've been able to conduct really successful MLFs. I
> found that the "trick" was to use the powdered Chris Hansen ML bacteria,
> use a
> healthy dose of ML nutrient, and do it at a 78-80 degree temperature.
> Now,
> after about 6-8 weeks, a ML chromatogram shows no malic acid spots, but
> there
> are still occasional tiny bubbles in the carboy. The wines haven't been
> sulfited yet.
>
> Should I expect the bubbles to COMPLETELY stop? I suspect that this won't
> happen, and I'm anxious to do a final racking and add some sulfite. So
> that's
> my first question: Do I have to wait for the MLF to COMPLETELY stop?

When my wines get to that point, I hit it with SO2, top up and bung tight.
If your wine is in a carboy, be careful about that last part though. Bung
it too tight and a temperature shift can blow the bottom out of the carboy.

> Secondly, I have a couple other batches of wine in various stages of their
> primary fermentations or completely finished which were never innoculated
> with
> ML and which were sulfited from the beginning. Just for the heck of it, I
> ran
> a chromatogram on those as well and while they have very obvious malic
> acid
> spots, they also have pretty prominent lactic acid spots. Does this mean
> that
> I have incomplete ML fermentations on those, or does lactic acid occur
> naturally?

That's a very good question that I can partially answer. I suspect that you
have spontaneous ML going on in that wine - especially if the pH is above
3.5.

Tom S

(pp) wrote:
> I was at a talk once by a guy who's a chemist and owns a store that
> sells all the fancy lab equipment to wineries. He said that the
> chromatography paper can only show malic spot when it's above certain,
> still significant concentration - don't remember the exact number. The
> rule of thumb he recommended was to wait for a couple of weeks after
> the spot first disappeared from the paper and then rack and sulfite.

That's true. Paper chromatography indicates malic acid concentrations
above about 100 mg/l. Wines may continue to undergo MLF over 30 mg/l
without showing any malic spot on the paper. Paper chromatography
should not be considered a quantitative test, only a qualitative test.
I agree with this chemists recommendations: wait a little before
sulphiting.

Ben

Improved Winemaking
http://members.tripod.com/~BRotter/MLF.htm

(pp) wrote:
> I was at a talk once by a guy who's a chemist and owns a store that
> sells all the fancy lab equipment to wineries. He said that the
> chromatography paper can only show malic spot when it's above certain,
> still significant concentration - don't remember the exact number. The
> rule of thumb he recommended was to wait for a couple of weeks after
> the spot first disappeared from the paper and then rack and sulfite.

That's true. Paper chromatography indicates malic acid concentrations
above about 100 mg/l. Wines may continue to undergo MLF over 30 mg/l
without showing any malic spot on the paper. Paper chromatography
should not be considered a quantitative test, only a qualitative test.
I agree with this chemists recommendations: wait a little before
sulphiting.

Ben

Improved Winemaking
http://members.tripod.com/~BRotter/MLF.htm

"LG1111" > wrote in message
...
> For the first season, I've been able to conduct really successful MLFs. I
> found that the "trick" was to use the powdered Chris Hansen ML bacteria,
use a
> healthy dose of ML nutrient, and do it at a 78-80 degree temperature.
Now,
> after about 6-8 weeks, a ML chromatogram shows no malic acid spots, but
there
> are still occasional tiny bubbles in the carboy. The wines haven't been
> sulfited yet.
>
> Should I expect the bubbles to COMPLETELY stop? I suspect that this won't
> happen, and I'm anxious to do a final racking and add some sulfite. So
that's
> my first question: Do I have to wait for the MLF to COMPLETELY stop? Or
will
> the sulfite do the job, or should I resort to lysozyme?
>
> Secondly, I have a couple other batches of wine in various stages of their
> primary fermentations or completely finished which were never innoculated
with
> ML and which were sulfited from the beginning. Just for the heck of it, I
ran
> a chromatogram on those as well and while they have very obvious malic
acid
> spots, they also have pretty prominent lactic acid spots. Does this mean
that
> I have incomplete ML fermentations on those, or does lactic acid occur
> naturally?
>
> Thanks, as always.
>
> Lee

Lee,
Wine contains little lactic acid before MLF. But, the yeast produces small
amounts of succinic acid during fermentation. On a chromatogram, the
succinic acid spots and the lactic acid spots are superimposed, so all wines
show a lactic/succinic acid spot before MLF.
Lum
Del Mar, California, USA

"LG1111" > wrote in message
...
> For the first season, I've been able to conduct really successful MLFs. I
> found that the "trick" was to use the powdered Chris Hansen ML bacteria,
use a
> healthy dose of ML nutrient, and do it at a 78-80 degree temperature.
Now,
> after about 6-8 weeks, a ML chromatogram shows no malic acid spots, but
there
> are still occasional tiny bubbles in the carboy. The wines haven't been
> sulfited yet.
>
> Should I expect the bubbles to COMPLETELY stop? I suspect that this won't
> happen, and I'm anxious to do a final racking and add some sulfite. So
that's
> my first question: Do I have to wait for the MLF to COMPLETELY stop? Or
will
> the sulfite do the job, or should I resort to lysozyme?
>
> Secondly, I have a couple other batches of wine in various stages of their
> primary fermentations or completely finished which were never innoculated
with
> ML and which were sulfited from the beginning. Just for the heck of it, I
ran
> a chromatogram on those as well and while they have very obvious malic
acid
> spots, they also have pretty prominent lactic acid spots. Does this mean
that
> I have incomplete ML fermentations on those, or does lactic acid occur
> naturally?
>
> Thanks, as always.
>
> Lee

Lee,
Wine contains little lactic acid before MLF. But, the yeast produces small
amounts of succinic acid during fermentation. On a chromatogram, the
succinic acid spots and the lactic acid spots are superimposed, so all wines
show a lactic/succinic acid spot before MLF.
Lum
Del Mar, California, USA