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
>
>