I remember as a kid 25 or 30 years ago, my brother Wayne or his
father-in-law Bob had a device that was able to measure alcohol content
after fermemtation. You put the liquid into it and blew air into it. I
remember seeing them test it using rye or vodka or something.

Dan



"FTAforever" > wrote in message
news
>I have just started brewing my own beer and wine. I have made so rather
>odd concoctions the process. Some of the wine tastes good, some bad, and
>some like there is no alcohol at all. I want to know how I can figure the
>alcohol content of a drink. Does anyone know a home method of measuring
>alcohol content?
>
>

"Daniel_B" > wrote in message
. ..
> I remember as a kid 25 or 30 years ago, my brother Wayne or his
> father-in-law Bob had a device that was able to measure alcohol content
> after fermemtation. You put the liquid into it and blew air into it. I
> remember seeing them test it using rye or vodka or something.
>
> Dan
>
I don't know about testing something =that= high in alcohol, but a
Vinometer is a glass funnel with a long tube on the bottom; you pour in DRY
wine and wait for it to drip out of the bottom, then invert it and wait to
see how far back down the tube the wine goes. You read it just like a
thermometer.
>
> "FTAforever" > wrote in message
> news
> >I have just started brewing my own beer and wine. I have made so rather
> >odd concoctions the process. Some of the wine tastes good, some bad, and
> >some like there is no alcohol at all. I want to know how I can figure
the
> >alcohol content of a drink. Does anyone know a home method of measuring
> >alcohol content?
> >
> >
>
>
>

"Daniel_B" > wrote in message
. ..
> I remember as a kid 25 or 30 years ago, my brother Wayne or his
> father-in-law Bob had a device that was able to measure alcohol content
> after fermemtation. You put the liquid into it and blew air into it. I
> remember seeing them test it using rye or vodka or something.
>
> Dan
>
I don't know about testing something =that= high in alcohol, but a
Vinometer is a glass funnel with a long tube on the bottom; you pour in DRY
wine and wait for it to drip out of the bottom, then invert it and wait to
see how far back down the tube the wine goes. You read it just like a
thermometer.
>
> "FTAforever" > wrote in message
> news
> >I have just started brewing my own beer and wine. I have made so rather
> >odd concoctions the process. Some of the wine tastes good, some bad, and
> >some like there is no alcohol at all. I want to know how I can figure
the
> >alcohol content of a drink. Does anyone know a home method of measuring
> >alcohol content?
> >
> >
>
>
>

"STEPHEN PEEK" > wrote in message link.net>...
> Seems both formulas work out quite closely. Using your formula on one of my
> typical mead fermentations: OG 1.120-FG 1.000= .120 x 105=12.6 x 1.25=15.75%
> ABV. My formula: gravity drop of 120 points divided by 7.49 (believe I had
> the wrong number above)= 16.02% ABV. Both are essentially correct & both are
> incorrect given that the lower density of alcohol screws up the hydrometer
> reading. I've never seen your formula before. It's interesting that 2 such
> different formulas come up with almost the same answer.
> Steve

They're not really different - 105 x 1.25 = 131.25, you're multiplying
by that. The other is gravity divided by 7.49 and gravity is 1000 x
specific gravity, so in specific gravity, you first multiply by 1000
and then divide by 7.49: 1000/7.49 = 133.5. So the first formula
multiplies sg by 131.25, second by 133.5.

These all seem to be variations on the formula/approach from Duncan
and Ainslie's Progressive Winemaking.

Pp

"STEPHEN PEEK" > wrote in message link.net>...
> Seems both formulas work out quite closely. Using your formula on one of my
> typical mead fermentations: OG 1.120-FG 1.000= .120 x 105=12.6 x 1.25=15.75%
> ABV. My formula: gravity drop of 120 points divided by 7.49 (believe I had
> the wrong number above)= 16.02% ABV. Both are essentially correct & both are
> incorrect given that the lower density of alcohol screws up the hydrometer
> reading. I've never seen your formula before. It's interesting that 2 such
> different formulas come up with almost the same answer.
> Steve

They're not really different - 105 x 1.25 = 131.25, you're multiplying
by that. The other is gravity divided by 7.49 and gravity is 1000 x
specific gravity, so in specific gravity, you first multiply by 1000
and then divide by 7.49: 1000/7.49 = 133.5. So the first formula
multiplies sg by 131.25, second by 133.5.

These all seem to be variations on the formula/approach from Duncan
and Ainslie's Progressive Winemaking.

Pp

"Jack Keller" > wrote in message
om...

<snip>

> Use a hydrometer. Measure specific gravity before pitching the yeast
> and again before bottling. The difference represents the change in
> density caused by the fermentation of sugar (now gone) into alcohol
> (still in the wine) and CO2 (hopefully, gone). Take the difference,
> add to 1.000, and use a look-up table to correlate that number with an
> alcohol level.
>
> Jack Keller, The Winemaking Home Page
> http://winemaking.jackkeller.net/

Hi Jack

Where can I find such a table ??

Frederick

"Jack Keller" > wrote in message
om...

<snip>

> Use a hydrometer. Measure specific gravity before pitching the yeast
> and again before bottling. The difference represents the change in
> density caused by the fermentation of sugar (now gone) into alcohol
> (still in the wine) and CO2 (hopefully, gone). Take the difference,
> add to 1.000, and use a look-up table to correlate that number with an
> alcohol level.
>
> Jack Keller, The Winemaking Home Page
> http://winemaking.jackkeller.net/

Hi Jack

Where can I find such a table ??

Frederick

"Jack Keller" > wrote in message
om...

<snip>

> Use a hydrometer. Measure specific gravity before pitching the yeast
> and again before bottling. The difference represents the change in
> density caused by the fermentation of sugar (now gone) into alcohol
> (still in the wine) and CO2 (hopefully, gone). Take the difference,
> add to 1.000, and use a look-up table to correlate that number with an
> alcohol level.
>
> Jack Keller, The Winemaking Home Page
> http://winemaking.jackkeller.net/

Hi Jack

Where can I find such a table ??

Frederick

"frederick ploegman" > wrote in message >...
> "Jack Keller" > wrote in message
> om...
>
> <snip>
>
> > Use a hydrometer. Measure specific gravity before pitching the yeast
> > and again before bottling. The difference represents the change in
> > density caused by the fermentation of sugar (now gone) into alcohol
> > (still in the wine) and CO2 (hopefully, gone). Take the difference,
> > add to 1.000, and use a look-up table to correlate that number with an
> > alcohol level.
> >
> > Jack Keller, The Winemaking Home Page
> > http://winemaking.jackkeller.net/
>
> Hi Jack
>
> Where can I find such a table ??
>
> Frederick

Frederick:

There is one on Jack's site, or Ben Rotter's site, or I think
Pambianchi's and other good winemaking books have one too.

Pp

"frederick ploegman" > wrote in message >...
> "Jack Keller" > wrote in message
> om...
>
> <snip>
>
> > Use a hydrometer. Measure specific gravity before pitching the yeast
> > and again before bottling. The difference represents the change in
> > density caused by the fermentation of sugar (now gone) into alcohol
> > (still in the wine) and CO2 (hopefully, gone). Take the difference,
> > add to 1.000, and use a look-up table to correlate that number with an
> > alcohol level.
> >
> > Jack Keller, The Winemaking Home Page
> > http://winemaking.jackkeller.net/
>
> Hi Jack
>
> Where can I find such a table ??
>
> Frederick

Frederick:

There is one on Jack's site, or Ben Rotter's site, or I think
Pambianchi's and other good winemaking books have one too.

Pp

"frederick ploegman" > wrote in message >...
> "Jack Keller" > wrote in message
> om...
>
> <snip>
>
> > Use a hydrometer. Measure specific gravity before pitching the yeast
> > and again before bottling. The difference represents the change in
> > density caused by the fermentation of sugar (now gone) into alcohol
> > (still in the wine) and CO2 (hopefully, gone). Take the difference,
> > add to 1.000, and use a look-up table to correlate that number with an
> > alcohol level.
> >
> > Jack Keller, The Winemaking Home Page
> > http://winemaking.jackkeller.net/
>
> Hi Jack
>
> Where can I find such a table ??
>
> Frederick

Frederick:

There is one on Jack's site, or Ben Rotter's site, or I think
Pambianchi's and other good winemaking books have one too.

Pp

"pp" > wrote in message
om...
> "frederick ploegman" > wrote in message
> >...
>> "Jack Keller" > wrote in message
>> om...
>>
>> <snip>
>>
>> > Use a hydrometer. Measure specific gravity before pitching the yeast
>> > and again before bottling. The difference represents the change in
>> > density caused by the fermentation of sugar (now gone) into alcohol
>> > (still in the wine) and CO2 (hopefully, gone). Take the difference,
>> > add to 1.000, and use a look-up table to correlate that number with an
>> > alcohol level.
>> >
>> > Jack Keller, The Winemaking Home Page
>> > http://winemaking.jackkeller.net/
>>
>> Hi Jack
>>
>> Where can I find such a table ??
>>
>> Frederick
>
> Frederick:
>
> There is one on Jack's site, or Ben Rotter's site, or I think
> Pambianchi's and other good winemaking books have one too.
>
> Pp

The only thing I find are "pre-pitch" (original gravity) tables. These
cannot be used in the manner stated above because it fails to consider
the effect that alcohol has on the "post ferment" reading. So far, I have
not seen a single answer in this thread that considers this, so the answers
thus obtained are wrong.

I am hoping that Jack or someone else here has a "post ferment/end
alcohol" table that they could share with us. Tables, after all, are
nothing more than a simple listing of all of the answers that a formula
can provide. They have the advantage that folks that can't even
_spell_the word algebra can look up the answers they need without
having to understand the math. So - if someone has a suitable formula,
it should be no problem converting it to a table.

Frederick

.. So - if someone has a suitable formula,
> it should be no problem converting it to a table.
>
> Frederick

Of course. No such table exists. And those who attempted to make
one soon discovered that their formula/method doesn't work. Let me
try (yet again) to explain this.

Example: Start a wine at 1.090. It finishes dry at 0.990. This is 100
points of SG drop. 90 of those points are due to the consumption and
conversion of sugar, and the other 10 points are attributable to the fact
that alcohol is less dense than water and therefore has an effect on our
*post ferment* reading (that was not present when we took our original
gravity reading). This 10 point drop contributed *nothing* toward the
amount of alcohol in the wine !!

Anyone who owns a triple scale hydrometer can do the following to
prove this to themselves:

Assemble the following materials:
1. Distilled water
2. Table sugar (pure cane)
3. Pure alcohol (Everclear will do)

Mix up the following solutions, measure and record the SG for each:
1. Plain water.
2. A 12% solution of alcohol and water.
3. A 22% solution of sugar and water.
4. A solution which contains BOTH 22% sugar AND 12% alcohol
with the remainder being water.

The first solution (plain water) is the reference point when we take our
original gravity readings.

The second solution is the reference point when we take our post ferment
(end gravity) readings.

The third solution is what we get when NO alcohol is influencing our
SG readings.

The fourth solution is what we_would_get if alcohol was influencing our
original gravity readings.

It will be seen that even though the 3rd and 4th solutions contain the
same amount of sugar, we get *very* different SG readings. The only
way to determine how much sugar is in solution 4 is to subtract the
influence that alcohol is having on that reading.

It should then be easy enough to understand that trying to compare one
reading that contains *no* alcohol to a second reading that *does* contain
alcohol is like comparing apples and oranges !! HTMS

Frederick

.. So - if someone has a suitable formula,
> it should be no problem converting it to a table.
>
> Frederick

Of course. No such table exists. And those who attempted to make
one soon discovered that their formula/method doesn't work. Let me
try (yet again) to explain this.

Example: Start a wine at 1.090. It finishes dry at 0.990. This is 100
points of SG drop. 90 of those points are due to the consumption and
conversion of sugar, and the other 10 points are attributable to the fact
that alcohol is less dense than water and therefore has an effect on our
*post ferment* reading (that was not present when we took our original
gravity reading). This 10 point drop contributed *nothing* toward the
amount of alcohol in the wine !!

Anyone who owns a triple scale hydrometer can do the following to
prove this to themselves:

Assemble the following materials:
1. Distilled water
2. Table sugar (pure cane)
3. Pure alcohol (Everclear will do)

Mix up the following solutions, measure and record the SG for each:
1. Plain water.
2. A 12% solution of alcohol and water.
3. A 22% solution of sugar and water.
4. A solution which contains BOTH 22% sugar AND 12% alcohol
with the remainder being water.

The first solution (plain water) is the reference point when we take our
original gravity readings.

The second solution is the reference point when we take our post ferment
(end gravity) readings.

The third solution is what we get when NO alcohol is influencing our
SG readings.

The fourth solution is what we_would_get if alcohol was influencing our
original gravity readings.

It will be seen that even though the 3rd and 4th solutions contain the
same amount of sugar, we get *very* different SG readings. The only
way to determine how much sugar is in solution 4 is to subtract the
influence that alcohol is having on that reading.

It should then be easy enough to understand that trying to compare one
reading that contains *no* alcohol to a second reading that *does* contain
alcohol is like comparing apples and oranges !! HTMS

Frederick

Frederick,

It seems to me that there is always an anomoly between final SG and
what you might predict anyway. This may due to SS and/or dissolved
substances in wine, which may vary from wine to wine.

To illustrate my point:
Assume you have a bone dry wine of 12% abv. The density of ethanol is
789 kg/m^3, that of water is 1000. Thus, the SG of this solution
should be:

SG = (0.12*789 + 0.88*1000)/1000 = 0.975

That's a far cry from the 0.990 we often see.

Agree?

Ben

"Ben Rotter" > wrote in message
om...
> Frederick,
>
> It seems to me that there is always an anomoly between final SG and
> what you might predict anyway. This may due to SS and/or dissolved
> substances in wine, which may vary from wine to wine.
>
> To illustrate my point:
> Assume you have a bone dry wine of 12% abv. The density of ethanol is
> 789 kg/m^3, that of water is 1000. Thus, the SG of this solution
> should be:
>
> SG = (0.12*789 + 0.88*1000)/1000 = 0.975
>
> That's a far cry from the 0.990 we often see.
>
> Agree?
>
> Ben

Ben,
Perhaps some of the difference is due to the 6 to 8 milligrams per litter of
titratable acid?
Lum
Del Mar, California, USA

"Ben Rotter" > wrote in message
om...
> Frederick,
>
> It seems to me that there is always an anomoly between final SG and
> what you might predict anyway. This may due to SS and/or dissolved
> substances in wine, which may vary from wine to wine.
>
> To illustrate my point:
> Assume you have a bone dry wine of 12% abv. The density of ethanol is
> 789 kg/m^3, that of water is 1000. Thus, the SG of this solution
> should be:
>
> SG = (0.12*789 + 0.88*1000)/1000 = 0.975
>
> That's a far cry from the 0.990 we often see.
>
> Agree?
>
> Ben

Ben,
Perhaps some of the difference is due to the 6 to 8 milligrams per litter of
titratable acid?
Lum
Del Mar, California, USA

"Ben Rotter" > wrote in message
om...
> Frederick,
>
> It seems to me that there is always an anomoly between final SG and
> what you might predict anyway. This may due to SS and/or dissolved
> substances in wine, which may vary from wine to wine.
>
> To illustrate my point:
> Assume you have a bone dry wine of 12% abv. The density of ethanol is
> 789 kg/m^3, that of water is 1000. Thus, the SG of this solution
> should be:
>
> SG = (0.12*789 + 0.88*1000)/1000 = 0.975
>
> That's a far cry from the 0.990 we often see.
>
> Agree?
>
> Ben

No, I don't agree. Just to be on the safe side, I actually made up a 12%
alcohol solution using Everclear and water from the tap. I am sitting
here now, watching my hydrometer float in that solution. It reads
0.990 !! Yup - I just checked it again and it is_still_reading 0.990.

Do the exercise that I outlined above. It will be_very_ revealing !!

Frederick

PS - what is "SS" ??

"Ben Rotter" > wrote in message
om...
> Frederick,
>
> It seems to me that there is always an anomoly between final SG and
> what you might predict anyway. This may due to SS and/or dissolved
> substances in wine, which may vary from wine to wine.
>
> To illustrate my point:
> Assume you have a bone dry wine of 12% abv. The density of ethanol is
> 789 kg/m^3, that of water is 1000. Thus, the SG of this solution
> should be:
>
> SG = (0.12*789 + 0.88*1000)/1000 = 0.975
>
> That's a far cry from the 0.990 we often see.
>
> Agree?
>
> Ben

No, I don't agree. Just to be on the safe side, I actually made up a 12%
alcohol solution using Everclear and water from the tap. I am sitting
here now, watching my hydrometer float in that solution. It reads
0.990 !! Yup - I just checked it again and it is_still_reading 0.990.

Do the exercise that I outlined above. It will be_very_ revealing !!

Frederick

PS - what is "SS" ??

Lum wrote:
> Perhaps some of the difference is due to the 6 to 8 milligrams per litter of
> titratable acid?

That was essentially the point I was originally making - thus my
comment "This may due to SS and/or dissolved substances in wine," e.g.
acids.

Frederick wrote:
> No, I don't agree. Just to be on the safe side, I actually made up a 12%
> alcohol solution using Everclear and water from the tap. I am sitting
> here now, watching my hydrometer float in that solution. It reads
> 0.990

I just did it (not Everclear, but similar product) and got pretty
close to 0.990. Perhaps the Everclear (or equivalent product) has
dissolved substances that contribute just like those in wine might?
Otherwise it simply doesn't make sense.

> PS - what is "SS" ??

Suspended solids.

Ben

Lum wrote:
> Perhaps some of the difference is due to the 6 to 8 milligrams per litter of
> titratable acid?

That was essentially the point I was originally making - thus my
comment "This may due to SS and/or dissolved substances in wine," e.g.
acids.

Frederick wrote:
> No, I don't agree. Just to be on the safe side, I actually made up a 12%
> alcohol solution using Everclear and water from the tap. I am sitting
> here now, watching my hydrometer float in that solution. It reads
> 0.990

I just did it (not Everclear, but similar product) and got pretty
close to 0.990. Perhaps the Everclear (or equivalent product) has
dissolved substances that contribute just like those in wine might?
Otherwise it simply doesn't make sense.

> PS - what is "SS" ??

Suspended solids.

Ben

"Ben Rotter" > wrote in message
om...
> Lum wrote:
> > Perhaps some of the difference is due to the 6 to 8 milligrams per
litter of
> > titratable acid?
>
> That was essentially the point I was originally making - thus my
> comment "This may due to SS and/or dissolved substances in wine," e.g.
> acids.
>
> Frederick wrote:
> > No, I don't agree. Just to be on the safe side, I actually made up a
12%
> > alcohol solution using Everclear and water from the tap. I am sitting
> > here now, watching my hydrometer float in that solution. It reads
> > 0.990
>
> I just did it (not Everclear, but similar product) and got pretty
> close to 0.990. Perhaps the Everclear (or equivalent product) has
> dissolved substances that contribute just like those in wine might?
> Otherwise it simply doesn't make sense.
>
> > PS - what is "SS" ??
>
> Suspended solids.
>
> Ben

I just looked up Table B-3, page 394 of "Commercial Winemaking" by Richard
Vine.
For a solution of 12 % by volume, the table gives a specific gravity of
0.98238.
For a solution of 12.09 % by weight, the table gives a specific gravity of
0.97897.
Now I'm even more confused.
--
Lum
Del Mar, California, USA

"Ben Rotter" > wrote in message
om...
> Lum wrote:
> > Perhaps some of the difference is due to the 6 to 8 milligrams per
litter of
> > titratable acid?
>
> That was essentially the point I was originally making - thus my
> comment "This may due to SS and/or dissolved substances in wine," e.g.
> acids.
>
> Frederick wrote:
> > No, I don't agree. Just to be on the safe side, I actually made up a
12%
> > alcohol solution using Everclear and water from the tap. I am sitting
> > here now, watching my hydrometer float in that solution. It reads
> > 0.990
>
> I just did it (not Everclear, but similar product) and got pretty
> close to 0.990. Perhaps the Everclear (or equivalent product) has
> dissolved substances that contribute just like those in wine might?
> Otherwise it simply doesn't make sense.
>
> > PS - what is "SS" ??
>
> Suspended solids.
>
> Ben

I just looked up Table B-3, page 394 of "Commercial Winemaking" by Richard
Vine.
For a solution of 12 % by volume, the table gives a specific gravity of
0.98238.
For a solution of 12.09 % by weight, the table gives a specific gravity of
0.97897.
Now I'm even more confused.
--
Lum
Del Mar, California, USA

Lum,
I am reluctant to chime in when you guys get going on the Chemistry,
but aren't most spirits such as Everclear distilled? Wouldn't that
esentially mean that it is alcohol only going into the bottle due to the
process thereby eliminating any solids? Just pondering I guess....
John Dixon


"Lum" > wrote in message
...
>
> "Ben Rotter" > wrote in message
> om...
> > Lum wrote:
> > > Perhaps some of the difference is due to the 6 to 8 milligrams per
> litter of
> > > titratable acid?
> >
> > That was essentially the point I was originally making - thus my
> > comment "This may due to SS and/or dissolved substances in wine," e.g.
> > acids.
> >
> > Frederick wrote:
> > > No, I don't agree. Just to be on the safe side, I actually made up a
> 12%
> > > alcohol solution using Everclear and water from the tap. I am sitting
> > > here now, watching my hydrometer float in that solution. It reads
> > > 0.990
> >
> > I just did it (not Everclear, but similar product) and got pretty
> > close to 0.990. Perhaps the Everclear (or equivalent product) has
> > dissolved substances that contribute just like those in wine might?
> > Otherwise it simply doesn't make sense.
> >
> > > PS - what is "SS" ??
> >
> > Suspended solids.
> >
> > Ben
>
> I just looked up Table B-3, page 394 of "Commercial Winemaking" by Richard
> Vine.
> For a solution of 12 % by volume, the table gives a specific gravity of
> 0.98238.
> For a solution of 12.09 % by weight, the table gives a specific gravity of
> 0.97897.
> Now I'm even more confused.
> --
> Lum
> Del Mar, California, USA
>
>

"J Dixon" > wrote in message
...
> Lum,
> I am reluctant to chime in when you guys get going on the Chemistry,
> but aren't most spirits such as Everclear distilled? Wouldn't that
> esentially mean that it is alcohol only going into the bottle due to the
> process thereby eliminating any solids? Just pondering I guess....
> John Dixon
>

John,
My only experience with Everclear was many, many years ago when I was in
college. I really don't know what Everclear puts in the bottles, but as I
remember, a good time was had by all.
--
Lum
Del Mar, California, USA

John,

> Wouldn't that esentially mean that it is alcohol only going into the
bottle due to the
> process thereby eliminating any solids?

That was my impression. In which case, it really doesn't seem to make
sense.

Ben

Ben wrote "Assume you have a bone dry wine of 12% abv. The density of
ethanol is
789 kg/m^3, that of water is 1000. Thus, the SG of this solution should be:
SG = (0.12*789 + 0.88*1000)/1000 = 0.975.

This would be true if the water and alcohol mixed without (for lack of a
better term this early in the morning) dissolving into each other. The two
liquids would have to remain separate at the molecular level even tho. mixed
together.

However, water and alcohol do form a solution where molecules of each liquid
intermingle and thus the specific gravity is different from the 0.975 value.
The rest of the differences seen are due to different hydrometers, different
temperatures at which measurements are made and other constituents in wine.

Lum's Commercial Winemaker reference gives the SG for 12% v/v alcohol as
0.98238. My Handbook of Chemistry and Physics gives the SG for this
solution as 0.98435 [at 15.56C]. This reference also says the SG at 4C is
0.98344. I'm sure both of these references took great care in their
measurements, yet there are differences.

Going back to the original question about how to calculate alcohol in dry
wine. I totally agree with Frederick (Nov.30 post) that you can only
consider the starting SG and a finished SG of 1.000 when you calculate
alcohol. Beyond this simple calculation you will need a Ebulliometer ($663
at piwine) for more accurate alcohol determinations.

BTW Lum, my college fraternity held Purple Passion parties and sold tickets.
Ten gallon crocks, grain alcohol (perhaps Everclear) and Welch's grape
juice with a large block of ice. Those were interesting evenings because
the mixture tasted just like grape juice. Creeped up on the guests real
fast.

Bill Frazier (DX)
Olathe, Kansas USA

"frederick ploegman" > wrote in message >...
>
> The only thing I find are "pre-pitch" (original gravity) tables. These
> cannot be used in the manner stated above because it fails to consider
> the effect that alcohol has on the "post ferment" reading. So far, I have
> not seen a single answer in this thread that considers this, so the answers
> thus obtained are wrong.
>
> I am hoping that Jack or someone else here has a "post ferment/end
> alcohol" table that they could share with us. Tables, after all, are
> nothing more than a simple listing of all of the answers that a formula
> can provide. They have the advantage that folks that can't even
> _spell_the word algebra can look up the answers they need without
> having to understand the math. So - if someone has a suitable formula,
> it should be no problem converting it to a table.
>
> Frederick

Frederick:

I certainly agree with you that alcohol will affect the final sg
reading, but I disagree with your conclusions in this thread. As you
say, a table just reflects an underlying formula. There are formulas
out there that use final sg reading to calculate the PA, so tables
based on these formulas then reflect both the starting and final sg.

To take one example, Duncan and Acton's Progressive Winemaking
mentions a simple formula PA = (Gs - Gf)/7.4, where G is the gravity,
defined as SG*1000. The constant 7.4 is actually an approximation -
they also give a more complicated formula, where the constant depends
on the starting gravity, but for simplicity, we can stick with the one
value 7.4 here.

The point is that this does not falsely increase the amount of sugar
in the must. Instead, the formula describes PA in terms of the total
drop in gravity during fermentation (which directly depends on the
sugar content of the must). As such, it's not better or worse by
itself than formulas that describe the PA only in terms of the initial
sg (sugar content). Which formula is better is an empirical question -
any formula gives only a rough estimate of the final alcohol, so the
quality of any formula would have to be measured against decent amount
of real data.

To continue with the above formula - since it's linear in terms of the
total gravity drop, we can use the method that Jack described and
shift the final gravity to 1000 (sg to 1.000) if we shift the initial
gravity by the same amount. And then a table that is based on this
formula will show the PA reading for the adjusted Gs - the adjustment
is needed because it allows us to start tabulating from sg 1.000.

One advantage of this approach is that it works equally well for all
wines - dry or sweet. Only the Gf reading is needed for all cases.
Formulas that work only with initial sg assume fermentation to
dryness. If there is significant residual sugar left, the PA has to be
adjusted, in which case one has to find out the RS amount and
manipulate the table accordingly. So in this case, the final sg value
becomes significant again.

The simple formula above also automatically corrects for presence of
solids because of the subtraction. In terms of precision, the book
claims the estimated PA is within +-0.5% of the actual value measured
by an ebullioscope, for the alcohol range 10-14%. That's about as good
as one could expect from any PA formula. The sample size is not
mentioned.

I personally don't use this formula, but I can see the value of this
approach. Mainly, I am hoping to make it clear here that approaches
like this don't really compare apples with oranges, as there is
nothing methodologically wrong in calculating PA in terms of total
gravity drop vs in terms of initial gravity only. What matters is
which formula makes a better prediction. In the absence of a decent
comparative study, the choice is up to individual winemakers'
preferences.

Pp

"frederick ploegman" > wrote in message >...
>
> The only thing I find are "pre-pitch" (original gravity) tables. These
> cannot be used in the manner stated above because it fails to consider
> the effect that alcohol has on the "post ferment" reading. So far, I have
> not seen a single answer in this thread that considers this, so the answers
> thus obtained are wrong.
>
> I am hoping that Jack or someone else here has a "post ferment/end
> alcohol" table that they could share with us. Tables, after all, are
> nothing more than a simple listing of all of the answers that a formula
> can provide. They have the advantage that folks that can't even
> _spell_the word algebra can look up the answers they need without
> having to understand the math. So - if someone has a suitable formula,
> it should be no problem converting it to a table.
>
> Frederick

Frederick:

I certainly agree with you that alcohol will affect the final sg
reading, but I disagree with your conclusions in this thread. As you
say, a table just reflects an underlying formula. There are formulas
out there that use final sg reading to calculate the PA, so tables
based on these formulas then reflect both the starting and final sg.

To take one example, Duncan and Acton's Progressive Winemaking
mentions a simple formula PA = (Gs - Gf)/7.4, where G is the gravity,
defined as SG*1000. The constant 7.4 is actually an approximation -
they also give a more complicated formula, where the constant depends
on the starting gravity, but for simplicity, we can stick with the one
value 7.4 here.

The point is that this does not falsely increase the amount of sugar
in the must. Instead, the formula describes PA in terms of the total
drop in gravity during fermentation (which directly depends on the
sugar content of the must). As such, it's not better or worse by
itself than formulas that describe the PA only in terms of the initial
sg (sugar content). Which formula is better is an empirical question -
any formula gives only a rough estimate of the final alcohol, so the
quality of any formula would have to be measured against decent amount
of real data.

To continue with the above formula - since it's linear in terms of the
total gravity drop, we can use the method that Jack described and
shift the final gravity to 1000 (sg to 1.000) if we shift the initial
gravity by the same amount. And then a table that is based on this
formula will show the PA reading for the adjusted Gs - the adjustment
is needed because it allows us to start tabulating from sg 1.000.

One advantage of this approach is that it works equally well for all
wines - dry or sweet. Only the Gf reading is needed for all cases.
Formulas that work only with initial sg assume fermentation to
dryness. If there is significant residual sugar left, the PA has to be
adjusted, in which case one has to find out the RS amount and
manipulate the table accordingly. So in this case, the final sg value
becomes significant again.

The simple formula above also automatically corrects for presence of
solids because of the subtraction. In terms of precision, the book
claims the estimated PA is within +-0.5% of the actual value measured
by an ebullioscope, for the alcohol range 10-14%. That's about as good
as one could expect from any PA formula. The sample size is not
mentioned.

I personally don't use this formula, but I can see the value of this
approach. Mainly, I am hoping to make it clear here that approaches
like this don't really compare apples with oranges, as there is
nothing methodologically wrong in calculating PA in terms of total
gravity drop vs in terms of initial gravity only. What matters is
which formula makes a better prediction. In the absence of a decent
comparative study, the choice is up to individual winemakers'
preferences.

Pp

"Lum" > wrote in message
news
>
> "Ben Rotter" > wrote in message
> om...
> > Frederick,
> >
> > It seems to me that there is always an anomoly between final SG and
> > what you might predict anyway. This may due to SS and/or dissolved
> > substances in wine, which may vary from wine to wine.
> >
> > To illustrate my point:
> > Assume you have a bone dry wine of 12% abv. The density of ethanol is
> > 789 kg/m^3, that of water is 1000. Thus, the SG of this solution
> > should be:
> >
> > SG = (0.12*789 + 0.88*1000)/1000 = 0.975
> >
> > That's a far cry from the 0.990 we often see.
> >
> > Agree?
> >
> > Ben
>
> Ben,
> Perhaps some of the difference is due to the 6 to 8 milligrams per litter
of
> titratable acid?

That little acid would have zero effect on sg. It's just not enough
mass.


> Lum
> Del Mar, California, USA
>
>

"J Dixon" > wrote in message
...
> Lum,
> I am reluctant to chime in when you guys get going on the Chemistry,
> but aren't most spirits such as Everclear distilled? Wouldn't that
> esentially mean that it is alcohol only going into the bottle due to the
> process thereby eliminating any solids? Just pondering I guess....
> John Dixon

Everclear is not 100% ethanol; it's about 95-97.5%. Pure ethanol is
hygroscopic, it rapidly absorbs water from the air.
>
> "Lum" > wrote in message
> ...
> >
> > "Ben Rotter" > wrote in message
> > om...
> > > Lum wrote:
> > > > Perhaps some of the difference is due to the 6 to 8 milligrams per
> > litter of
> > > > titratable acid?
> > >
> > > That was essentially the point I was originally making - thus my
> > > comment "This may due to SS and/or dissolved substances in wine," e.g.
> > > acids.
> > >
> > > Frederick wrote:
> > > > No, I don't agree. Just to be on the safe side, I actually made up
a
> > 12%
> > > > alcohol solution using Everclear and water from the tap. I am
sitting
> > > > here now, watching my hydrometer float in that solution. It reads
> > > > 0.990
> > >
> > > I just did it (not Everclear, but similar product) and got pretty
> > > close to 0.990. Perhaps the Everclear (or equivalent product) has
> > > dissolved substances that contribute just like those in wine might?
> > > Otherwise it simply doesn't make sense.
> > >
> > > > PS - what is "SS" ??
> > >
> > > Suspended solids.
> > >
> > > Ben
> >
> > I just looked up Table B-3, page 394 of "Commercial Winemaking" by
Richard
> > Vine.
> > For a solution of 12 % by volume, the table gives a specific gravity of
> > 0.98238.
> > For a solution of 12.09 % by weight, the table gives a specific gravity
of
> > 0.97897.
> > Now I'm even more confused.
> > --
> > Lum
> > Del Mar, California, USA
> >
> >
>
>

"J Dixon" > wrote in message
...
> Lum,
> I am reluctant to chime in when you guys get going on the Chemistry,
> but aren't most spirits such as Everclear distilled? Wouldn't that
> esentially mean that it is alcohol only going into the bottle due to the
> process thereby eliminating any solids? Just pondering I guess....
> John Dixon

Everclear is not 100% ethanol; it's about 95-97.5%. Pure ethanol is
hygroscopic, it rapidly absorbs water from the air.
>
> "Lum" > wrote in message
> ...
> >
> > "Ben Rotter" > wrote in message
> > om...
> > > Lum wrote:
> > > > Perhaps some of the difference is due to the 6 to 8 milligrams per
> > litter of
> > > > titratable acid?
> > >
> > > That was essentially the point I was originally making - thus my
> > > comment "This may due to SS and/or dissolved substances in wine," e.g.
> > > acids.
> > >
> > > Frederick wrote:
> > > > No, I don't agree. Just to be on the safe side, I actually made up
a
> > 12%
> > > > alcohol solution using Everclear and water from the tap. I am
sitting
> > > > here now, watching my hydrometer float in that solution. It reads
> > > > 0.990
> > >
> > > I just did it (not Everclear, but similar product) and got pretty
> > > close to 0.990. Perhaps the Everclear (or equivalent product) has
> > > dissolved substances that contribute just like those in wine might?
> > > Otherwise it simply doesn't make sense.
> > >
> > > > PS - what is "SS" ??
> > >
> > > Suspended solids.
> > >
> > > Ben
> >
> > I just looked up Table B-3, page 394 of "Commercial Winemaking" by
Richard
> > Vine.
> > For a solution of 12 % by volume, the table gives a specific gravity of
> > 0.98238.
> > For a solution of 12.09 % by weight, the table gives a specific gravity
of
> > 0.97897.
> > Now I'm even more confused.
> > --
> > Lum
> > Del Mar, California, USA
> >
> >
>
>

"B0B" > wrote in message
...
>
> "Lum" > wrote in message
> news
> >
> > "Ben Rotter" > wrote in message
> > om...
> > > Frederick,
> > >
> > > It seems to me that there is always an anomoly between final SG and
> > > what you might predict anyway. This may due to SS and/or dissolved
> > > substances in wine, which may vary from wine to wine.
> > >
> > > To illustrate my point:
> > > Assume you have a bone dry wine of 12% abv. The density of ethanol is
> > > 789 kg/m^3, that of water is 1000. Thus, the SG of this solution
> > > should be:
> > >
> > > SG = (0.12*789 + 0.88*1000)/1000 = 0.975
> > >
> > > That's a far cry from the 0.990 we often see.
> > >
> > > Agree?
> > >
> > > Ben
> >
> > Ben,
> > Perhaps some of the difference is due to the 6 to 8 milligrams per
litter
> of
> > titratable acid?
>
> That little acid would have zero effect on sg. It's just not enough
> mass.
>
>

Hi Bob,

Sorry about the milligrams per liter typo. Factors of 1000 are usually
significant, so thanks for pointing out my error.

Here is what I meant to say.

About 1.7 Brix of sugar has the potential for producing 1% (v/v) of alcohol
(see "Concepts in Wine Chemistry," page 57).
1 gram of sugar in 99 grams of water = 1 percent by weight = 1 Brix.
10 grams of dissolved solids in 990 grams of water = 1 percent by weight = 1
Brix.
Six to eight grams of dissolved solids (acids) per liter is equivalent to
0.6 to
0.8 Brix..
If 1.7 Brix = about 1% alcohol, then 0.8 percent of dissolved solids would
be roughly equivalent to 0.47% alcohol (0.8/1.7 x 1% alcohol).

Regards,
Lum
Del Mar, California, USA

I don't know where I'm jumping into this thread, but something tells
me to trust my cheap old $5 hydrometer only down to about 1.000.

Not knowing the specifications behind hydrometer design, I would
venture to guess that the design to measure brix and granualarity down
to 1.000 is lost when you try to design one to measure below 1.000.

I consider my stuff dry below when I get to .990, based on the lowest
level on my hydrometer and the converstaions in this group. The
interesting thing is that I have never had a reading below .990, even
if the stuff is still fermenting.

Something tells me that a longer tube filled with less air would do
the trick for <1.000 SG, but then wouldn't a cheap alternative be on
the market for us to use instead of the vinometer?
Greg



On Sat, 4 Dec 2004 13:51:47 -0500, "B0B" > wrote:

>
>"Lum" > wrote in message
>news
>>
>> "Ben Rotter" > wrote in message
>> om...
>> > Frederick,
>> >
>> > It seems to me that there is always an anomoly between final SG and
>> > what you might predict anyway. This may due to SS and/or dissolved
>> > substances in wine, which may vary from wine to wine.
>> >
>> > To illustrate my point:
>> > Assume you have a bone dry wine of 12% abv. The density of ethanol is
>> > 789 kg/m^3, that of water is 1000. Thus, the SG of this solution
>> > should be:
>> >
>> > SG = (0.12*789 + 0.88*1000)/1000 = 0.975
>> >
>> > That's a far cry from the 0.990 we often see.
>> >
>> > Agree?
>> >
>> > Ben
>>
>> Ben,
>> Perhaps some of the difference is due to the 6 to 8 milligrams per litter
>of
>> titratable acid?
>
> That little acid would have zero effect on sg. It's just not enough
>mass.
>
>
>> Lum
>> Del Mar, California, USA
>>
>>
>

Hoss > wrote in message >. ..
> I don't know where I'm jumping into this thread, but something tells
> me to trust my cheap old $5 hydrometer only down to about 1.000.
>
> Not knowing the specifications behind hydrometer design, I would
> venture to guess that the design to measure brix and granualarity down
> to 1.000 is lost when you try to design one to measure below 1.000.
>
> I consider my stuff dry below when I get to .990, based on the lowest
> level on my hydrometer and the converstaions in this group. The
> interesting thing is that I have never had a reading below .990, even
> if the stuff is still fermenting.
>
> Something tells me that a longer tube filled with less air would do
> the trick for <1.000 SG, but then wouldn't a cheap alternative be on
> the market for us to use instead of the vinometer?
> Greg
>
>

You're correct about the regular hydrometer, byt you can get narrow
range hydrometers for about $20 that have scales for example between
1.000 and 0.980 sg, so these are specifically designed to measure the
final sg correctly. I would assume that was the hydrometer used for
these experiments.

Pp

"William Frazier" > wrote in message
...
>
> Going back to the original question about how to calculate alcohol in dry
> wine. I totally agree with Frederick (Nov.30 post) that you can only
> consider the starting SG and a finished SG of 1.000 when you calculate
> alcohol. Beyond this simple calculation you will need a Ebulliometer
> ($663 at piwine) for more accurate alcohol determinations.
>
>
> Bill Frazier (DX)

Hi Bill

Thank you. I know that you understand this, but the way you framed your
statement leaves it wide open to be misinterpreted by others here.
CJJ Berry understood it this way and_still_managed to get messed up.
What folks need to understand here is that the influence of alcohol
changes the reference point (if you will) and that this has to be
compensated for to restore the reference point _back_ to SG 1.000
so that such a calculation _can_ be made. IOW - so we are
comparing an apple to an apple and _not_ an apple to an orange.
Clear as mud, right?? Maybe you can come up with some IOWs to
help explain this. TIA

Frederick

"Ben Rotter" > wrote in message
om...
> Lum wrote:
>> Perhaps some of the difference is due to the 6 to 8 milligrams per litter
>> of
>> titratable acid?
>
> That was essentially the point I was originally making - thus my
> comment "This may due to SS and/or dissolved substances in wine," e.g.
> acids.
>
> Frederick wrote:
>> No, I don't agree. Just to be on the safe side, I actually made up a 12%
>> alcohol solution using Everclear and water from the tap. I am sitting
>> here now, watching my hydrometer float in that solution. It reads
>> 0.990
>
> I just did it (not Everclear, but similar product) and got pretty
> close to 0.990. Perhaps the Everclear (or equivalent product) has
> dissolved substances that contribute just like those in wine might?
> Otherwise it simply doesn't make sense.
>
>> PS - what is "SS" ??
>
> Suspended solids.
>
> Ben

Hi all

Gone for a while hunting (got a nice 7 point). Now that I am back, I find
so many posts that I hardly know where to begin. I_would_like to answer
a few of the posts in this thread however, in the hope that someone
besides Bill will arrive at an understanding of this topic.

Everyone should understand that the numbers I am using here are_very_
generously rounded off in an effort to keep this simple. After all, the
only point I am trying to make is that there is NO _fixed_ relationship
between SG and PA. Sg measures _total_ solutes (both fermentable
AND non-fermentable), while alcohol is calculated using _only_ the
fermentable portion of that total. The exercise outlined above is just
the simplest way I could think of to demonstrate this in a way that
everyone here could do, even if they are "theory" challenged. ;o)
(nothing better than something you can see with your own eyes)

Ben

If your theories are so compelling that you can doubt the evidence of
your own eyes, there is little I can do to help you understand what is
going on with this stuff. My approach to winemaking is strictly
pragmatic and I use my own empirical data to make these kinds of
estimates. My own understanding of theory is imperfect so I can't
address the subject that way. Might I refer you to the UC Davis site
where, in the second to the last para on page 10, you will find an example
of the formula they use to calculate the PA numbers that are used on
our hydrometers. The pages leading up to that example contain a _very_
good explanation of how they arrive at those numbers. Hopefully this
will also explain why I have been saying that you can"t get more alcohol
in the wine than the original PA perdicts. HTH

Frederick

PP

I have been over the material in this book a number of times with
several people (I thought you were one of them). But - let me try to
plod through it again. Comments interspersed:

"pp" > wrote in message
om...
> "frederick ploegman" > wrote in message
> >...
>>
>> The only thing I find are "pre-pitch" (original gravity) tables. These
>> cannot be used in the manner stated above because it fails to consider
>> the effect that alcohol has on the "post ferment" reading. So far, I
>> have
>> not seen a single answer in this thread that considers this, so the
>> answers
>> thus obtained are wrong.
>>
>> I am hoping that Jack or someone else here has a "post ferment/end
>> alcohol" table that they could share with us. Tables, after all, are
>> nothing more than a simple listing of all of the answers that a formula
>> can provide. They have the advantage that folks that can't even
>> _spell_the word algebra can look up the answers they need without
>> having to understand the math. So - if someone has a suitable formula,
>> it should be no problem converting it to a table.
>>
>> Frederick
>
> Frederick:
>
> I certainly agree with you that alcohol will affect the final sg
> reading, but I disagree with your conclusions in this thread. As you
> say, a table just reflects an underlying formula. There are formulas
> out there that use final sg reading to calculate the PA, so tables
> based on these formulas then reflect both the starting and final sg.
>

Such formulas use an ADJUSTED final gravity and_not_the ACTUAL
final gravity !!

> To take one example, Duncan and Acton's Progressive Winemaking
> mentions a simple formula PA = (Gs - Gf)/7.4, where G is the gravity,
> defined as SG*1000. The constant 7.4 is actually an approximation -

Read this again_veeeery_carefully. G is defined as having a reference of
1.000. This means BOTH Gs AND Gf !! So long as they both share the
same reference point, then yes, this formula will work. BUT (big but),
folks don't understand this and they _try_ to use their ACTUAL end SG
reading when using this formula. If Gf is NOT restored to a reference
point of 1.000 by compensating for the effect of alcohol on the final
gravity reading, this formula does NOT work !! Gee whiz. This is what
I have been_trying_ to explain all along !! From the rest of what you
say here, I suspect that you are still making this same mistake yourself.

> they also give a more complicated formula, where the constant depends
> on the starting gravity, but for simplicity, we can stick with the one
> value 7.4 here.

Not what I use, but "good enough", IF Gf is adjusted.

>
> The point is that this does not falsely increase the amount of sugar
> in the must.

It _does_have this effect when Gf is _not_ adjusted.

>Instead, the formula describes PA in terms of the total
> drop in gravity during fermentation (which directly depends on the
> sugar content of the must).

I would view this statement as wrong in this particular context. Only
_part_ of the total drop is caused by the consumption of fermentable
sugars. The _rest_of the drop is due to the effect of alcohol on our
end SG reading. However, (to avoid another nit) if this statement is
taken to mean that the amount of drop is dependent on the amount of
fermentable sugars available to the yeast, then yes I can buy that.

>As such, it's not better or worse by
> itself than formulas that describe the PA only in terms of the initial
> sg (sugar content).

Wrong. PA is based _solely_ on the amount of fermentable sugars
available to the yeast. Let me say once more - there is NO FIXED
RELATIONSHIP BETWEEN SG AND PA !! SG is a measure of
_total_solutes (not just the sugar).

>Which formula is better is an empirical question -

Nope.

> any formula gives only a rough estimate of the final alcohol,

Estimate yes, rough no.

>so the
> quality of any formula would have to be measured against decent amount
> of real data.

Every country and every state that has any interest at all in having a
winemaking industry has government funded labs which lack for
nothing by way of facilities and the best and most modern equipment.
These are staffed by people who spend entire_life_ times dedicated to
winemaking research. This being the case, how can you even_imagine_
such data does not already exist and has not already been incorporated
into the things we use ?? (eg the PA scale on our hydrometers, etc..)

>
> To continue with the above formula - since it's linear in terms of the
> total gravity drop, we can use the method that Jack described and
> shift the final gravity to 1000 (sg to 1.000) if we shift the initial
> gravity by the same amount.

Wrong, wrong, wrong !! The final gravity_does_ need to be shifted,
but the original gravity is_not_effected by the presence of alcohol so it
does_not_have to be shifted. (It_already_has a reference point of
1.000) Which of course is my whole point here.
BOTH readings have to share the SAME reference point !!

>And then a table that is based on this
> formula will show the PA reading for the adjusted Gs - the adjustment
> is needed because it allows us to start tabulating from sg 1.000.

Nope - see above. In view of my previous answers here, I won't go
on with this at this time. HTH and HTMS

Frederick

>
> Pp

Ben Rotter wrote:


>
> It seems to me that there is always an anomoly between final SG and
> what you might predict anyway. ,

<Snip>

Ben,

I think I know partly why (although I haven't checked the exact
mathematics). I seem to recall from my High School Chemistry class that
water molecules and alcohol molecules fit into each other in such a way
that the total volume of the mixture is less than the volumes of the two
liquids unmixed. That is, if you add 20 ml ethanol to 80 ml water,
you'll get noticeably less than 100 ml as a result. It's a difference of
a few percent, IIRC. That means that the mixture has all of the mass of
the two liquids, but less than their additive volumes. It seems to me
that this would increase the mixture's density by about that same few
percent, maybe accounting for the difference between the predicted
density of .975 and the observed density of .990 . It's only a
difference of about 1.5% that we're talking about.

Supporting data can be seen in the chart at the end of this link,
http://www.miracosta.edu/home/dlr/210exp5.htm , but they don't quite
seem to match the exact difference, either.

It looks like this is another case of Reality thumbing its nose at our
neat predictions.

--


Mike MTM, Cokesbury, New Jersey, USA

Took me a while to figure out I had to switch to Google beta to be able
to post... and now I don't seem to be able to quote the previous
message to respond to explicit points. Hmm, hopefully that'll get
ironed out soon.

Frederick, can you supply a better reference than "the UC Davis site" -
I can't find any reference to PA articles there, nor anything
resembling page 10. I'd really like to read this article as it seems to
be the primary source of your PA stance.

Thx,

Pp