ACID %
 

Hi gang,
Been making my own wine for quite a few years, but I just got serious
about supplying all my beverage needs myself.
My question is this:
Books on the subject say the must should be ".60-.80% acid as expressed
in tartaric acid". What I'm wondering is if it is better to err on the high
side, as I've read that some acid is metabolized by the yeast so that as it
ferments you have less acid with a less effective/complete fermentation, OR
if running things on the low side is better?
Anyone want to chime in with what percentage of acid, expressed as
tartaric, you shoot for? I ask this because I've had a few batches turn out
with plenty of sugar left over. I go for 13% alcohol and wind up with 11%
and sweetness to boot.
Bob

I forgot to mention that =most= of the wines I make are =not= grape
wines. I do a lot with various fruits, and also meads. Sooooo, I am
adjusting pH with acid blend, malic, citric and ascorbic IIRC.

ACID %
 

Bob,

> Books on the subject say the must should be ".60-.80% acid as expressed
> in tartaric acid". What I'm wondering is if it is better to err on the high
> side, as I've read that some acid is metabolized by the yeast so that as it
> ferments you have less acid with a less effective/complete fermentation, OR
> if running things on the low side is better?

Actually, that depends on the yeast and the environment (e.g. pH,
nutrients). Yeasts also *produce* acids during fermentation. With
non-grape wines, the production of acid during fermentation usually
tends to be *higher* than the metabolism of acid by the yeast (except
in cases where the yeast is particularly efficient at metabolising
acids - e.g. strain 71B-1122) plus tartrate precipitation doesn't tend
to occur unless a significant amount of the acidity in the must was
tartaric (i.e. by using acid blend or tartaric to acidify the must).

It's highly unlikely that a stuck fermentation would be the result of
acid *production during fermentation*. However, musts with very low
pHs tend to assist in causing sticking. (On that, fermentation
temperature and yeast nutrients are more of an issue.)

Ray suggested the easiest method - to adjust acidity
post-fermentation. Some winemakers feel that by doing that the acidity
somehow doesn't "integrate" so well into the wine, others disagree.
The acidity of the must *can* be adjusted pre-fermentation, by knowing
roughly where it's at (measuring the TA) and where it will go
(estimates of acid production during fermentation), a reasonably
accurate estimate can be made. The TA of the must can then be adjusted
based on the final level.

> Anyone want to chime in with what percentage of acid, expressed as
> tartaric, you shoot for? I ask this because I've had a few batches turn out
> with plenty of sugar left over. I go for 13% alcohol and wind up with 11%
> and sweetness to boot.

Where the TA should be pre-fermentation really depends where you want
it to end up, and that depends on the style of wine. For example, a
non-tartaric must has TA of 6 g/l (0.6%) and a pH of 3.3. The final
wine will not go through MLF. It's desired to have a final level of 6
g/l. Estimated TA increase during fermentation is 2 g/l. Thus, the
must's TA will need to be dropped by 2 g/l (chemical deacidification).
Alternatively, a yeast strain like 71B-1122 or MLF could be used.

Ben

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

ACID %
 

WOW! Great answer!!! THANKS!!!
"Ben Rotter" > wrote in message
om...
> Bob,
>
> > Books on the subject say the must should be ".60-.80% acid as
expressed
> > in tartaric acid". What I'm wondering is if it is better to err on the
high
> > side, as I've read that some acid is metabolized by the yeast so that as
it
> > ferments you have less acid with a less effective/complete fermentation,
OR
> > if running things on the low side is better?
>
> Actually, that depends on the yeast and the environment (e.g. pH,
> nutrients). Yeasts also *produce* acids during fermentation. With
> non-grape wines, the production of acid during fermentation usually
> tends to be *higher* than the metabolism of acid by the yeast (except
> in cases where the yeast is particularly efficient at metabolising
> acids - e.g. strain 71B-1122) plus tartrate precipitation doesn't tend
> to occur unless a significant amount of the acidity in the must was
> tartaric (i.e. by using acid blend or tartaric to acidify the must).
>
> It's highly unlikely that a stuck fermentation would be the result of
> acid *production during fermentation*. However, musts with very low
> pHs tend to assist in causing sticking. (On that, fermentation
> temperature and yeast nutrients are more of an issue.)
>
> Ray suggested the easiest method - to adjust acidity
> post-fermentation. Some winemakers feel that by doing that the acidity
> somehow doesn't "integrate" so well into the wine, others disagree.
> The acidity of the must *can* be adjusted pre-fermentation, by knowing
> roughly where it's at (measuring the TA) and where it will go
> (estimates of acid production during fermentation), a reasonably
> accurate estimate can be made. The TA of the must can then be adjusted
> based on the final level.
>
> > Anyone want to chime in with what percentage of acid, expressed as
> > tartaric, you shoot for? I ask this because I've had a few batches turn
out
> > with plenty of sugar left over. I go for 13% alcohol and wind up with
11%
> > and sweetness to boot.
>
> Where the TA should be pre-fermentation really depends where you want
> it to end up, and that depends on the style of wine. For example, a
> non-tartaric must has TA of 6 g/l (0.6%) and a pH of 3.3. The final
> wine will not go through MLF. It's desired to have a final level of 6
> g/l. Estimated TA increase during fermentation is 2 g/l. Thus, the
> must's TA will need to be dropped by 2 g/l (chemical deacidification).
> Alternatively, a yeast strain like 71B-1122 or MLF could be used.
>
> Ben
>
> Improved Winemaking
> http://members.tripod.com/~BRotter/

ACID %
 

Ben, I agree that it is best to have the acid in the must up front so it
all integrates properly, but I don't feel that small adjustments are a
problem at the end and I hate trying to bring it down. I want to be close
but I would rather take it up a bit at the end. I will generally do what I
suggested. I aim low the first time I make a new wine. Keep records and
adjust the amount of acid I add when I make it again. Really, after making
a wine a couple of times, I rarely have to adjust it at the end. Or not
much anyway.

Ray

"Ben Rotter" > wrote in message
om...
> Bob,
>
> > Books on the subject say the must should be ".60-.80% acid as
expressed
> > in tartaric acid". What I'm wondering is if it is better to err on the
high
> > side, as I've read that some acid is metabolized by the yeast so that as
it
> > ferments you have less acid with a less effective/complete fermentation,
OR
> > if running things on the low side is better?
>
> Actually, that depends on the yeast and the environment (e.g. pH,
> nutrients). Yeasts also *produce* acids during fermentation. With
> non-grape wines, the production of acid during fermentation usually
> tends to be *higher* than the metabolism of acid by the yeast (except
> in cases where the yeast is particularly efficient at metabolising
> acids - e.g. strain 71B-1122) plus tartrate precipitation doesn't tend
> to occur unless a significant amount of the acidity in the must was
> tartaric (i.e. by using acid blend or tartaric to acidify the must).
>
> It's highly unlikely that a stuck fermentation would be the result of
> acid *production during fermentation*. However, musts with very low
> pHs tend to assist in causing sticking. (On that, fermentation
> temperature and yeast nutrients are more of an issue.)
>
> Ray suggested the easiest method - to adjust acidity
> post-fermentation. Some winemakers feel that by doing that the acidity
> somehow doesn't "integrate" so well into the wine, others disagree.
> The acidity of the must *can* be adjusted pre-fermentation, by knowing
> roughly where it's at (measuring the TA) and where it will go
> (estimates of acid production during fermentation), a reasonably
> accurate estimate can be made. The TA of the must can then be adjusted
> based on the final level.
>
> > Anyone want to chime in with what percentage of acid, expressed as
> > tartaric, you shoot for? I ask this because I've had a few batches turn
out
> > with plenty of sugar left over. I go for 13% alcohol and wind up with
11%
> > and sweetness to boot.
>
> Where the TA should be pre-fermentation really depends where you want
> it to end up, and that depends on the style of wine. For example, a
> non-tartaric must has TA of 6 g/l (0.6%) and a pH of 3.3. The final
> wine will not go through MLF. It's desired to have a final level of 6
> g/l. Estimated TA increase during fermentation is 2 g/l. Thus, the
> must's TA will need to be dropped by 2 g/l (chemical deacidification).
> Alternatively, a yeast strain like 71B-1122 or MLF could be used.
>
> Ben
>
> Improved Winemaking
> http://members.tripod.com/~BRotter/

ACID %
 

One comment on meads since Bob mentioned that; my acid always rises
and pH drops as it ferments. I usually add juice of half a dozen or a
dozen lemons to 6 gallons (US)and it seems to end up around 6 to 6.5
g/l with a pH of 2.8. That pH would lead you to think it's tart, but
I usually end up doing as Ray says, touching up the acid (upward) at
the end, at least on mead. All honey is different results vary.
Regards,
Joe


"Ray" > wrote in message m>...
> Ben, I agree that it is best to have the acid in the must up front so it
> all integrates properly, but I don't feel that small adjustments are a
> problem at the end and I hate trying to bring it down. I want to be close
> but I would rather take it up a bit at the end. I will generally do what I
> suggested. I aim low the first time I make a new wine. Keep records and
> adjust the amount of acid I add when I make it again. Really, after making
> a wine a couple of times, I rarely have to adjust it at the end. Or not
> much anyway.
>
> Ray

ACID %
 

"Joe Sallustio" > wrote in message
om...
> One comment on meads since Bob mentioned that; my acid always rises
> and pH drops as it ferments. I usually add juice of half a dozen or a
> dozen lemons to 6 gallons (US)and it seems to end up around 6 to 6.5
> g/l with a pH of 2.8. That pH would lead you to think it's tart, but
> I usually end up doing as Ray says, touching up the acid (upward) at
> the end, at least on mead. All honey is different results vary.
> Regards,
> Joe
Honey is =hugely= variable! Nothing about it is ever the same. Only a
brand name like Sue-Bee is even close to the same. Every batch of mead for
the last 25 years has been different.
What I do as it finishes fermenting, is drop in campden tabs to kill off
stuff, and add 5 whole =cloves= per gallon, let it settle to clarity, rack
it off the lees and put preservative into the fresh carboy and let it go
another year at least.
Not many other hobbies take so long to see results!
>
> "Ray" > wrote in message
m>...
> > Ben, I agree that it is best to have the acid in the must up front so
it
> > all integrates properly, but I don't feel that small adjustments are a
> > problem at the end and I hate trying to bring it down. I want to be
close
> > but I would rather take it up a bit at the end. I will generally do
what I
> > suggested. I aim low the first time I make a new wine. Keep records
and
> > adjust the amount of acid I add when I make it again. Really, after
making
> > a wine a couple of times, I rarely have to adjust it at the end. Or not
> > much anyway.
> >
> > Ray

ACID %
 

"Ray" > wrote:
> Ben, I agree that it is best to have the acid in the must up front so it
> all integrates properly, but I don't feel that small adjustments are a
> problem at the end and I hate trying to bring it down. I want to be close
> but I would rather take it up a bit at the end. I will generally do what I
> suggested. I aim low the first time I make a new wine. Keep records and
> adjust the amount of acid I add when I make it again. Really, after making
> a wine a couple of times, I rarely have to adjust it at the end. Or not
> much anyway.

Sure, it's the most convenient way. I totally agree that with a bit of
experience it's possible to get a feel of where the acidity will go
and thus aim for it. Of course, this is the normal approach when
dealing with meads or diluted fruit musts, use of more fruit is a
different story.

(Joe Sallustio) wrote:
> dozen lemons to 6 gallons (US)and it seems to end up around 6 to 6.5
> g/l with a pH of 2.8. That pH would lead you to think it's tart, but

Are you talking about dry mead here?

Ben

ACID %
 

I didn't say it wasn't variable, I would not argue that. Mine is not
that unpredictable since it comes from the same hives each time. Fall
flow and spring flow are different as you would expect. The point I
was getting at was that wine and mead behave differently during
fermentation. My mead pH drops an order of magnitude, it really
suprised me the first time.
Regards,
Joe


> Honey is =hugely= variable! Nothing about it is ever the same. Only a
> brand name like Sue-Bee is even close to the same. Every batch of mead for
> the last 25 years has been different.

ACID %
 

I recently read "The Complete Meadmaker" by Ken Schramm. In it he suggests
that for mead you should not try to adjust the pH and acidity before you
ferment. It seems that mead has natural buffers that will effect the way
the acid ends up in strange ways and that if you try to adjust acidity up
front you can end up in a place that you did not want to go and that you may
even cause the mead to stick. This is all from what I read. I know that in
my last batch of mead I thought I adjusted it up front and when if finished
I was way far away from what I expected and I had to add a lot of acid.

Ray

"Joe Sallustio" > wrote in message
om...
> I didn't say it wasn't variable, I would not argue that. Mine is not
> that unpredictable since it comes from the same hives each time. Fall
> flow and spring flow are different as you would expect. The point I
> was getting at was that wine and mead behave differently during
> fermentation. My mead pH drops an order of magnitude, it really
> suprised me the first time.
> Regards,
> Joe
>
>
> > Honey is =hugely= variable! Nothing about it is ever the same. Only
a
> > brand name like Sue-Bee is even close to the same. Every batch of mead
for
> > the last 25 years has been different.

ACID %
 

For the most part, it usually ends up around 12% ABV and 2% RS. It's
not really sweet. We use between 12 and 14 pounds of honey to 5
gallons (US) to make around 6 gallons preferment.
Regards,
Joe



> (Joe Sallustio) wrote:
> > dozen lemons to 6 gallons (US)and it seems to end up around 6 to 6.5
> > g/l with a pH of 2.8. That pH would lead you to think it's tart, but
>
> Are you talking about dry mead here?
>
> Ben