If you have too many solids you probably should filter some juice with a
better filter than the straining bag. When you do your measurement you
should use something that really looks like juice rather than nectar. That
does not mean it is clear but you probably know what I mean. Even if you
get good clear juice there will still be solids that effect the reading.
You could use an approach that subtracts out the effect of these solids.
One such approach is given by Acton and Duncan in "Progressive Winemaking"
where they use SG or G. Another is advanced by UCLA where they use Brix. I
use the first of these two.

My equations derived form theirs are as follows:

% Alcohol = (Go - Gf) / F

Where Go is original gravity and Gf is final gravity and gravity is defined
as

G = (SG-1)*1000.

And F is a value that takes into account the non-fermentable solids in the
must and is defined

F = 7.75 - 3*(Go - 7) / 800

To get potential alcohol with this method you must guess the final G and
then when it is finished you can use the actual final G to determine the
true alcohol level. If you use Gf = 0, you will get the potential alcohol
that is given in most tables or on the hydrometer which is not what you will
really get as the result of fermentation. A good guess for final value is
SG = 0.995 or G = -5.

Ray

"Barry" > wrote in message
om...
> I'm a budding home winemaker.
>
> Getting a good S.G. reading that I can trust after the cap falls, and
> settling starts is pretty easy.
>
> I'd like to know what procedures people use to do the initial reading.
> There are so many solids in the fresh must, even using the juice I
> get through a straining bag (especially if some non-grape fruits are
> used)... my level of confidence in the readings I get at the beginning
> is pretty low.
>
> I did a Toka plum wine which started at like 1.130 when the must did
> not seem overly sweet to the taste. I don't believe the reading.
>
> How do you guys deal with this?