Erroll Ozgencil wrote:
> We use hydrometers to gauge sugar content. Since hydrometers measure
> solubles solids and soluble solids are mostly sugar in wine grapes,
> that works pretty well. In researching raspberries, I found that sugar
> can make up a much smaller fraction in other fruit. A clear sample of
> raspberry juice might measure 9 Brix, but contain only 3 g/100g sugar.
> More detail he
>
> http://www.washingtonwinemaker.com/b...ur-hydrometer/
>
> If we're just talking about raspberries, that may not be a big deal.
> It's unusual to make wine from 100% raspberry juice - I've never done
> it with more than 25%. So, for the entire must, the error is a lot
> smaller. Might be a problem with other fruit though.
>
> Erroll
> http://www.washingtonwinemaker.com/

Well, this is why the big winemakers send their samples to a lab with
GC/MS and titration equipment. Of course, they have much more to lose if
they have an "off" batch.

I guess the big deal for us hydrometer users is that non-assimilable
solutes contribute to density in the same way as assimilable solutes,
and the hydrometer can't tell us what the ratio is. However, it can tell
us how much assimilable solute has been metabolized by the yeast, which
is still a useful piece of information.

Marshall