"Droopy" > wrote in message
oups.com...
>
> David C Breeden wrote:
> > William Frazier ) wrote:
> > >Thanks for the info. Dave. Do you know if the remaining fructose can
be
> > >fermented which would have an effect on the bottle pressure of a
sparkling
> > >wine? If fructose is the end of the line the Glucometer still might be
> > >worth using to test for residule fermentable sugar.
> >
> > >Bill Frazier
> > >Olathe, Kansas USA
> >
> > Hey Bill,
> >
> > My understanding is that yeast CAN metabolize fructose, but prefer
> > gluocse. My fermentation stuck at 1% fructose, and wouldn't go
> > again until I added glucose.
> >
> > But I don't know if you can count on that.
> >
> > Dave
> >
************************************************** **************************
> > Dave Breeden

>
>
> Fructose is fully metabolizable. The major metabolic pathway for sugar
> is called glycolysis. Normally an enzyme called glucokinase uses
> glucose into glucose 6 phosphate, which is then turned into fructose 6
> phosphate.. There is another less specific enzyme (hexokinase) that
> can utilize several 6 carbon sugars, including fructose and make
> fructose 6 phosphate.
>
>
> The problem with clintest I believe is that it tests for REDUCING
> sugars. That is it uses the reduction of copper to affect a color
> change. The problem with wine is that there are many things that can
> reduce the copper. Sulfite is a reducing agent for instance....so are
> the anthocyanins in red wine.

Very interesting post Droopy.
Thank you.
Could you provide a reference for "anthocyanins being a reducing agent for
copper?"
Lum
Del Mar, California, USA