"JG" > wrote in message
news
> Lum Eisenman wrote:
> > "JG" > wrote in message
> > . net...
> >> Lum Eisenman wrote:
> >>> "Ric" > wrote in message
> >>> ...
> >>>> Are you real sure of the numbers, Lum? I don't have my chem texts
with
> >>>> me right now - will check tomorrow - but 3 ppm of copper sulfate
sounds
> >>>> pretty high --- anyone know the 'safe' limits of CuSO4? I thought it
> > was
> >>>> in the neighborhood of something less than 1 ppm.
> >>>>
> >>>> Personally, I wouldn't want to drink wine with anything like 'too
much'
> >>>> CuSO4 in it.
> >>>>
> >>>> At the very least - JG might want to consider bentonite fining the
> > wine
> >>>> in the hope of dropping some copper ions?
> >>>>
> >>>>
> >>>>> Don't dump that wine yet Joe.
> >>>>> The label on my jar of vitamins says........"each tablet contains 3
> >>>>> milligrams of copper (150% of the minimum daily requirement)." If
> > your
> >>> wine
> >>>>> contains 3 milligrams of copper per liter, one 750 liter bottle of
> > wine
> >>>>> would contain 2.25 milligrams of copper or just about the MDR of
> > copper.
> >>>>> I would drink the wine. But, I would make sure I didn't drink more
> > than
> >>> 3
> >>>>> or 4 bottles per day.
> >>>>> Lum
> >>>>> Del Mar, California, USA
> >>>>> www.geocities.com/lumeisenman
> >>> I am NOT real sure of the numbers Rick.
> >>> I am sure of the quote from the label on my vitamin bottle.
> >>> I am also sure that Bentonite will not remove any significant amount
of
> >>> copper from wine. But, fining with dry yeast can reduce the copper
> > content
> >>> of wine considerably.
> >>> Lum
> >>>
> >>>
> >> Lum,
> >> Can you outline the procedure for removing copper with dry yeast?
> >>
> >> Thanks,
> >> Joe
> >
> > The procedure is very simple Joe.
> >
> > Add dry yeast to the wine, stir, rack the wine off the yeast lees after
a
> > week or two.
> >
> > Apparently, the metal ions adhere to the yeast sell membrane and are
removed
> > when the wine is racked off the yeast lees. Old (dead) yeast seems to
be as
> > good as fresh yeast, so I always save any old yeast just in case I need
it
> > to remove metal ion. I have used as much as 50 grams of dry yeast per
> > 5-gallons of wine.
> >
> > Lum
> > Del Mar, California, USA
> > www.geocities.com/lumeisenman
> >
> >
> Lum,
> So about 10 grams per gallon of yeast then give/take? How long should
> it take to remove some of the copper? I suspect I will wait until the
> yeast settles to the bottom. Will it have done the job by then? Its
> $22 to test a sample for Cu conc. I am thinking about doing a
> before/after to see how much was removed.
>
> Thanks,
> Joe

Joe,

You have a lot of copper in your wine so the yeast may not get the copper
level down to a desirable level. But in my experience, several grams of dry
yeast per gallon of wine will remove a significant amount of copper.

I think the reaction between yeast cells and metal ions is fast. But, it
will takes a week or so for the yeast to settle so the wine can be racked
off of the yeast and adhering copper.

Good luck,
Lum