PA scale is an indication of where you might end up. You still have to
calculate where you actually ended up when the fermentation is over.

Ray

"frederick ploegman" > wrote in message
...
> What is the purpose and function of the PA scale on my hydrometer ??
>
>

"Ray" > wrote in message m>...
> PA scale is an indication of where you might end up. You still have to
> calculate where you actually ended up when the fermentation is over.
>
> Ray
>
>

PA is Potential Alcohol, an estimate of the alochol content if all of
the sugar is consumed. If any sugar is left in the must, you will not
reach this potential.

Andy

I am very serious about this question. I can site references that state
differently that what you say. Can you give me accepted, published
references that agree with your statement?

Ray

"JEP" > wrote in message
om...
> "Ray" > wrote in message
m>...
> > PA scale is an indication of where you might end up. You still have to
> > calculate where you actually ended up when the fermentation is over.
> >
> > Ray
> >
> >
>
> PA is Potential Alcohol, an estimate of the alochol content if all of
> the sugar is consumed. If any sugar is left in the must, you will not
> reach this potential.
>
> Andy

"Ray" > wrote in message
. ..
> I am very serious about this question. I can site references that state
> differently that what you say. Can you give me accepted, published
> references that agree with your statement?
>
> Ray
>
> "JEP" > wrote in message
> om...
> > "Ray" > wrote in message
> m>...
> > > PA scale is an indication of where you might end up. You still have
to
> > > calculate where you actually ended up when the fermentation is over.
> > >
> > > Ray
> > >
> > >
> >
> > PA is Potential Alcohol, an estimate of the alochol content if all of
> > the sugar is consumed. If any sugar is left in the must, you will not
> > reach this potential.
> >
> > Andy

Ray & Andy,

One mole of sugar produces 2 moles of alcohol. The molecular weight of
sugar is 180 and the molecular weight of ethanol is 46. So theoretically,
180 grams of sugar can produce 92 grams of alcohol. 92 divided by 180 is
..511 or 51.1 percent.

But in practical fermentations, only 90 - 92 percent of the sugar produces
ethanol. The rest of the sugar produces higher alcohols, acetaldehyde,
succinic acid, etc.

In addition, some alcohol is blown off by the escaping carbon dioxide gas.

See Margalit, "Concepts in Wine Chemistry," page 56.

Regards,
lum

Thanks Lum but that is not what I am looking for. I know all that. I can
calculate the theoretical, maximum yield but I want the practical yield.
What I really am looking for is published raw data on beginning and ending
SG (or equivalent) and actual measured alcohol in the finished wine using a
laboratory determination rather than charts. I am embroiled in a dispute
with certain parties as a result of the article on determining alcohol that
I published in WineMaker. I have good references to accepted publications
that that state what the tables that are but I have not found raw data that
really verifies their tables and how they should be used. I have tried to
get this type of information from a number of laboratories that should have
it but have not been successful. (I am not willing to pay for it, that is
why I want published numbers.) If anyone can come up the this type of
information I would be really grateful.

Ray


"Lum" > wrote in message
...
>
> "Ray" > wrote in message
> . ..
> > I am very serious about this question. I can site references that state
> > differently that what you say. Can you give me accepted, published
> > references that agree with your statement?
> >
> > Ray
> >
> > "JEP" > wrote in message
> > om...
> > > "Ray" > wrote in message
> > m>...
> > > > PA scale is an indication of where you might end up. You still have
> to
> > > > calculate where you actually ended up when the fermentation is over.
> > > >
> > > > Ray
> > > >
> > > >
> > >
> > > PA is Potential Alcohol, an estimate of the alochol content if all of
> > > the sugar is consumed. If any sugar is left in the must, you will not
> > > reach this potential.
> > >
> > > Andy
>
> Ray & Andy,
>
> One mole of sugar produces 2 moles of alcohol. The molecular weight of
> sugar is 180 and the molecular weight of ethanol is 46. So theoretically,
> 180 grams of sugar can produce 92 grams of alcohol. 92 divided by 180 is
> .511 or 51.1 percent.
>
> But in practical fermentations, only 90 - 92 percent of the sugar produces
> ethanol. The rest of the sugar produces higher alcohols, acetaldehyde,
> succinic acid, etc.
>
> In addition, some alcohol is blown off by the escaping carbon dioxide gas.
>
> See Margalit, "Concepts in Wine Chemistry," page 56.
>
> Regards,
> lum
>
>

"Ray" > wrote in message
m...
> Thanks Lum but that is not what I am looking for. I know all that. I can
> calculate the theoretical, maximum yield but I want the practical yield.
> What I really am looking for is published raw data on beginning and ending
> SG (or equivalent) and actual measured alcohol in the finished wine using
a
> laboratory determination rather than charts. I am embroiled in a dispute
> with certain parties as a result of the article on determining alcohol
that
> I published in WineMaker. I have good references to accepted publications
> that that state what the tables that are but I have not found raw data
that
> really verifies their tables and how they should be used. I have tried to
> get this type of information from a number of laboratories that should
have
> it but have not been successful. (I am not willing to pay for it, that is
> why I want published numbers.) If anyone can come up the this type of
> information I would be really grateful.
>
> Ray

Ray,

I have not followed this discussion, so please pardon my ignorance.

I hope the following data is of interest to you.

Starting Finished
Brix Brix Alc. 1 Alc. 2 Alc. 3
24.3 -1.6 13.0 13.2 12.6
24.1 -1.4 13.1 - 12.8
22.8 -1.7 12.4 - -
23.5 -1.5 12.4 12.7 -
25.1 -1.3 13.6 13.7 -
23.2 -1.5 12.3 12.4 12.2

These data from a few wines made in my garage over the past few years. All
are red fermentations done in !/2 ton fruit bins without temperature
control. The time from starting Brix to finished Brix is 7 to 10 days,
except for the 25.1 Brix fermentation. It was hot and fast and finished in
5 days.

The first column is the starting Brix.
The second column is finished Brix.
The third column is the alcohol measured by my home made ebulliometer.
The fourth column is the alcohol measured by a well calibrated commercial
ebulliometer.
The fifth column is the alcohol measured by a standard distillation method.

Regards,
Lum
Del Mar, California, USA

Ray
A good library will have Polarimetry, Saccarimetry and the Sugars by
Bates, NBS Circular C440. It's out of print, a 1942 publication.
NIST still uses it. It is a definitive text but it's pretty deep. If
your regular library does not have it, try a nearby college. (We have
several copies here in Pittsburgh, NIST recommended the book to me a
few years ago when I had similar questions and I had a hard time
finding it; once I found one copy a few other sources became obvious.)

I have a copy and can email you an excel spreadsheet with values taken
from the book, but the bottom line is outside influences make
prediction of alcohol content an approximation only. They used
standardzed sucrose solutions for the values, not juice. I corrected
the tables for the changes in our understanding of mass and volume;
they are miniscule, but I did it anyway.

Lum,
I have though about making my own ebulliometer since they are so
pricey. I have a good RTD somewhere, how hard was it to make the
boiling chamber? I was wondering if I could just use a boiling flask
and stopper. Could you share your setup and tables?
Regards,
Joe





"Lum" > wrote in message >...
> "Ray" > wrote in message
> m...
> > Thanks Lum but that is not what I am looking for. I know all that. I can
> > calculate the theoretical, maximum yield but I want the practical yield.
> > What I really am looking for is published raw data on beginning and ending
> > SG (or equivalent) and actual measured alcohol in the finished wine using
> a
> > laboratory determination rather than charts. I am embroiled in a dispute
> > with certain parties as a result of the article on determining alcohol
> that
> > I published in WineMaker. I have good references to accepted publications
> > that that state what the tables that are but I have not found raw data
> that
> > really verifies their tables and how they should be used. I have tried to
> > get this type of information from a number of laboratories that should
> have
> > it but have not been successful. (I am not willing to pay for it, that is
> > why I want published numbers.) If anyone can come up the this type of
> > information I would be really grateful.
> >
> > Ray
>
> Ray,
>
> I have not followed this discussion, so please pardon my ignorance.
>
> I hope the following data is of interest to you.
>
> Starting Finished
> Brix Brix Alc. 1 Alc. 2 Alc. 3
> 24.3 -1.6 13.0 13.2 12.6
> 24.1 -1.4 13.1 - 12.8
> 22.8 -1.7 12.4 - -
> 23.5 -1.5 12.4 12.7 -
> 25.1 -1.3 13.6 13.7 -
> 23.2 -1.5 12.3 12.4 12.2
>
> These data from a few wines made in my garage over the past few years. All
> are red fermentations done in !/2 ton fruit bins without temperature
> control. The time from starting Brix to finished Brix is 7 to 10 days,
> except for the 25.1 Brix fermentation. It was hot and fast and finished in
> 5 days.
>
> The first column is the starting Brix.
> The second column is finished Brix.
> The third column is the alcohol measured by my home made ebulliometer.
> The fourth column is the alcohol measured by a well calibrated commercial
> ebulliometer.
> The fifth column is the alcohol measured by a standard distillation method.
>
> Regards,
> Lum
> Del Mar, California, USA

"Lum" > wrote in message >...
> Ray & Andy,
>
> One mole of sugar produces 2 moles of alcohol. The molecular weight of
> sugar is 180 and the molecular weight of ethanol is 46. So theoretically,
> 180 grams of sugar can produce 92 grams of alcohol. 92 divided by 180 is
> .511 or 51.1 percent.
>
> But in practical fermentations, only 90 - 92 percent of the sugar produces
> ethanol. The rest of the sugar produces higher alcohols, acetaldehyde,
> succinic acid, etc.
>
> In addition, some alcohol is blown off by the escaping carbon dioxide gas.
>
> See Margalit, "Concepts in Wine Chemistry," page 56.
>
> Regards,
> lum

Ar a recent talk, a professional winemaker here from BC mentioned that
they were getting higher alcohol levels for the starting Brix than
they used to, often by 1% or even more. She said this was confirmed by
other winemakers from the area. Her hypothesis was that the yeast were
getting more efficient in alcohol production. This could have large
repercussions if that were indeed the case. I'm wondering if this is
happening in other, hotter areas, as well?

Pp
Vancouver, Canada

"pp" > wrote in message
om...
> "Lum" > wrote in message
>...
> > Ray & Andy,
> >
> > One mole of sugar produces 2 moles of alcohol. The molecular weight of
> > sugar is 180 and the molecular weight of ethanol is 46. So
theoretically,
> > 180 grams of sugar can produce 92 grams of alcohol. 92 divided by 180
is
> > .511 or 51.1 percent.
> >
> > But in practical fermentations, only 90 - 92 percent of the sugar
produces
> > ethanol. The rest of the sugar produces higher alcohols, acetaldehyde,
> > succinic acid, etc.
> >
> > In addition, some alcohol is blown off by the escaping carbon dioxide
gas.
> >
> > See Margalit, "Concepts in Wine Chemistry," page 56.
> >
> > Regards,
> > lum
>
> Ar a recent talk, a professional winemaker here from BC mentioned that
> they were getting higher alcohol levels for the starting Brix than
> they used to, often by 1% or even more. She said this was confirmed by
> other winemakers from the area. Her hypothesis was that the yeast were
> getting more efficient in alcohol production. This could have large
> repercussions if that were indeed the case. I'm wondering if this is
> happening in other, hotter areas, as well?
>
> Pp
> Vancouver, Canada

Some types of wine yeast produce more alcohol than others, so the above
situation certainly seems possible. But, I don't understand what the "large
repercussions" would be.
Lum
Del Mar, California, USA

"Lum" > wrote in message news:<uutAc.480> >
> > Ar a recent talk, a professional winemaker here from BC mentioned that
> > they were getting higher alcohol levels for the starting Brix than
> > they used to, often by 1% or even more. She said this was confirmed by
> > other winemakers from the area. Her hypothesis was that the yeast were
> > getting more efficient in alcohol production. This could have large
> > repercussions if that were indeed the case. I'm wondering if this is
> > happening in other, hotter areas, as well?
> >
> > Pp
> > Vancouver, Canada
>
> Some types of wine yeast produce more alcohol than others, so the above
> situation certainly seems possible. But, I don't understand what the "large
> repercussions" would be.
> Lum
> Del Mar, California, USA

Well, if the yeast got consistenly more efficient in producing
alcohol, then the winemaking practice would have to adjust to that
somehow, particularly in hot areas, otherwise we'd end up with hot,
unbalanced wines, no? 1% is a lot as an average change.

I believe she's been using the same yeast over the years, so it's not
a change in the type of yeast.

Pp
Vancouver, BC, Canada

Could you locate contact information, name, or whatever, for the person
giving the talk. If you can, you could pass it to me directly at my email
rather than putting it on the news group. (They may or may not appreciate
that.)

Ray

"pp" > wrote in message
om...
> "Lum" > wrote in message
>...
> > Ray & Andy,
> >
> > One mole of sugar produces 2 moles of alcohol. The molecular weight of
> > sugar is 180 and the molecular weight of ethanol is 46. So
theoretically,
> > 180 grams of sugar can produce 92 grams of alcohol. 92 divided by 180
is
> > .511 or 51.1 percent.
> >
> > But in practical fermentations, only 90 - 92 percent of the sugar
produces
> > ethanol. The rest of the sugar produces higher alcohols, acetaldehyde,
> > succinic acid, etc.
> >
> > In addition, some alcohol is blown off by the escaping carbon dioxide
gas.
> >
> > See Margalit, "Concepts in Wine Chemistry," page 56.
> >
> > Regards,
> > lum
>
> Ar a recent talk, a professional winemaker here from BC mentioned that
> they were getting higher alcohol levels for the starting Brix than
> they used to, often by 1% or even more. She said this was confirmed by
> other winemakers from the area. Her hypothesis was that the yeast were
> getting more efficient in alcohol production. This could have large
> repercussions if that were indeed the case. I'm wondering if this is
> happening in other, hotter areas, as well?
>
> Pp
> Vancouver, Canada