John,

I guess what I really wanted to say was that in all my research, I
haven't found any documentation that says yeast cells can be smaller
than 4 microns. Actually, only one paper mentioned the 4 microns and
all others had 5 as the lower limit for WINE yeast cell size. I know
..45 absolute is needed for MLB BUT if the filter doesn't bind , I don't
see why a 3 micron or 1 micron filter wouldn't be enough to filter out
yeast cells. Now with that said, I use 1 micron in series with .35
micron for my filtering because I've been scared half to death by the
posters here ,BUT I'm just curious if anyone has had any luck
filtering out yeast with bigger micron sizes besides what is generally
recommended here. Thanks for all the responses.

Bob


J Dixon wrote:
> Bob,
> I have never bottled using one of the type of filters you
indicated,
> but I have heard stories of those who have which included fizzy and
> exploding bottles, corks ejected etc.
> The "riskiest" method I use is to take a .45 micron nominal
cartridge
> filter and use it in line with my bottle filler as my only
filtration.
> (using NO Sorbate). I have found in my situation that this has been a
> reasonable method so long as you ensure the filter is not becoming
"blinded"
> or plugged up as Lum stated. It certainly is safer to use an Absolute
filter
> of .45 or less, but the cost is about tripled for the filters so I
have been
> using the Nominals with good luck. The other point I was trying to
make is
> that Yeast is floating around in the air all the time, and if you
filter
> your wine and then let it bulk age without Sorbate you may get a
> refermentation. Never tried it, but I dont think it's a good idea in
my
> opinion to filter without Sorbate and let the wine bulk age. HTH
> John Dixon
>
> > wrote in message
> ups.com...
> > John,
> >
> > Just curious, has anyone filtered with a .5 - 1 micron filter and
have
> > re-fermentation happen after bottling with R/S? According to the
size
> > of yeast cells , anything below 5 microns should filter them out.
Do we
> > have any winemakers out there with examples of re-fermentation or
is
> > the caution just been handed down from generation to generation
without
> > actual instances of this hapenning??
> >
> > Bob
> >
> >
> > J Dixon wrote:
> > > Joe's advice is good. When you add your sorbate should depend
more on
> > the
> > > clarity of the wine now. More specifically is it real clear and
will
> > you be
> > > stirring it up to add the Sorbate? If so, then I would filter and
> > then
> > > Sorbate. Another point of view might be that you are not in a
great
> > hurry
> > > and dont care if it gets stirred up a bit (it always clears out
> > faster the
> > > second time anyways). If you do this you can put off the
filtering
> > and limit
> > > the handling by eliminating one racking theoretically. Either way
> > make sure
> > > your sulphite levels are up before you add the Sorbate so you
dont
> > have
> > > another problem. In any case I would not count on a .5 micron
> > eliminating a
> > > fermentation completely especially if you plan to let it sit
around
> > in a
> > > carboy before bottling it later.HTH
> > > John Dixon
> > > "Joe Sallustio" > wrote in message
> > > ups.com...
> > > > WD,
> > > > It depends. when you say 0.5 micron filter, that can mean two
> > things.
> > > > If you are going to sterile filter with an 0.5 micron
_absolute_
> > filter
> > > > that should be fine, but it's very difficult to sterile filter.
> > > >
> > > > If you are talking about a Buon Vino plate and frame 'sterile'
> > filter
> > > > it is not an absolute filter. Yeast is pretty creative, it
doesn't
> > > > take much to have a fermentation restart. If your wine is good
and
> > > > clear chances of refermentation happening are slim, but it is
> > possible.
> > > >
> > > >
> > > > I use the Buon Vino 'sterile' filter on sweet whites, but I add
> > sorbate
> > > > since I do not trust it. 2 or 3 percent RS is enough to create
a
> > hand
> > > > grenade if it referments to dry. You would see a yeast layer
form
> > in
> > > > the bottle if that occured. Some people can taste sorbate, most
> > can't.
> > > > If you want to use that it's often used to good effect by small
> > scale
> > > > winemakers. I filter and sorbate the end product, wait a few
days
> > at
> > > > least to ensure it is still and bottle.
> > > >
> > > > Another option you have is to bottle it and leave it cold. If
you
> > are
> > > > not talking about a lot of wine you may want to consider just
> > bottling
> > > > and keeping it at 40F or so; anything under 50F is usually
enough
> > to
> > > > keep most yeast strains from restarting. A sweet wine is
usually
> > served
> > > > cold, so it may be an option to consider. No filter, no
sorbate,
> > just
> > > > keep it cold.
> > > >
> > > > Joe
> > > >
> > > > Kiva wrote:
> > > > > I have a Riesling I started last fall. I stopped the
fermentation
> > by
> > > > putting
> > > > > the carboys into a cold refrigerator at about 28-30 degrees
F.
> > The
> > > > result is
> > > > > what I wanted, approximately 2%-3% residual sugar. I added
> > bentonite
> > > > along
> > > > > with the cold stabilization. I am now ready to take out of
the
> > cold
> > > > and
> > > > > rack.
> > > > >
> > > > > 1) Should I run it through the filter .5 micron and add
sorbate?
> > > > >
> > > > > 2) or rack and sorbate now and then filter later?
> > > > >
> > > > >
> > > > >
> > > > > Thanks in advance for any help
> > > > >
> > > > > WD
> > > >
> >