I have a Riesling I have fermented dry. I now want to add back some of
the original unfermented juice to add sweetness. I do not want to add
sorbate. Will the Buon Super Jet number three filter ( .5 micron )
take out enough of the yeast to stop another fermentation? I have
cold stabilized and the wine is now clear. Should I just add in the
juice and then filter?

WD

"WD" > wrote in message
om...
> I have a Riesling I have fermented dry. I now want to add back some of
> the original unfermented juice to add sweetness. I do not want to add
> sorbate. Will the Buon Super Jet number three filter ( .5 micron )
> take out enough of the yeast to stop another fermentation? I have
> cold stabilized and the wine is now clear. Should I just add in the
> juice and then filter?

I'm with you on not liking to use sorbate, but that's not a tight enough
filtration to achieve sterility. You need a 0.45µ _absolute_ filter to
remove all the yeast cells. That pad filter is 0.5µ _nominal_, so it will
let some yeast cells slip past. Sorry. :^(

Tom S

I've had the same question about the Buon Vino filters. With all of the people
who use their filters, you'd think that they would have addressed the
discrepancies between their pore size and the size of yeast cells. Are there
any alternative filters that might fit into the Buon Vino? Alternatively, what
are the other available filters that get down to the appropriate size?

Lee

Lee,

I only use my Buon Vino filter rarely, and am not an expert on
filtration, but from what I've read, it's not so much an issue of pore
size, but of the nature of the pores. A membrane filter is basically a
thin sheet with lots of uniformly sized holes. the hole size is said to
be "absolute", as there are no larger ones. A depth filter, like the
Buon Vino pads, has a lot of different sized holes or channels, which
have an average, or nominal, size. As Tom points out, since there are
pores larger than the nominal size, there's a certain amount of larger
stuff that gets past. Just because the pads are rated .5 microns doesn't
mean they will stop everything of, say, one micron. <sigh> It takes a
better tool than a Buon Vino, I'm afraid. Even if one could contrive an
absolute filter for one, it probably wouldn't have the pressure to work.

If anyone has found a way to do it, though, I'm all ears.

HTH, Mike MTM

"MikeMTM" > wrote in message
...
> Lee,
>
> I only use my Buon Vino filter rarely, and am not an expert on
> filtration, but from what I've read, it's not so much an issue of pore
> size, but of the nature of the pores. A membrane filter is basically a
> thin sheet with lots of uniformly sized holes. the hole size is said to
> be "absolute", as there are no larger ones. A depth filter, like the
> Buon Vino pads, has a lot of different sized holes or channels, which
> have an average, or nominal, size. As Tom points out, since there are
> pores larger than the nominal size, there's a certain amount of larger
> stuff that gets past. Just because the pads are rated .5 microns doesn't
> mean they will stop everything of, say, one micron. <sigh> It takes a
> better tool than a Buon Vino, I'm afraid. Even if one could contrive an
> absolute filter for one, it probably wouldn't have the pressure to work.

That covers the subject of pad filtration pretty well.

> If anyone has found a way to do it, though, I'm all ears.

You buy a 10" 0.45µ membrane cartridge, an Ametek (or equivalent) housing
for it, some plastic fittings and hose. Hook the membrane cartridge in
series with the output of the pad filter. Presto! Sterile wine. :^)

Although membrane cartridges are expensive, you can re-use it many times if
the wine you run through it is well filtered to begin with.

Tom S

> You buy a 10" 0.45µ membrane cartridge, an Ametek (or equivalent) housing
> for it, some plastic fittings and hose. Hook the membrane cartridge in
> series with the output of the pad filter. Presto! Sterile wine. :^)
>
> Although membrane cartridges are expensive, you can re-use it many times if
> the wine you run through it is well filtered to begin with.


Tom,
What's the rough price of the entire system?

Don

Tom, take a look at this website www.mcmaster.com type in Item # 43765K14
and click on catalog page. Is this like the filter you are talking about?

WD

"Tom S" > wrote in message
m...
>
> "MikeMTM" > wrote in message
> ...
> > Lee,
> >
> > I only use my Buon Vino filter rarely, and am not an expert on
> > filtration, but from what I've read, it's not so much an issue of pore
> > size, but of the nature of the pores. A membrane filter is basically a
> > thin sheet with lots of uniformly sized holes. the hole size is said to
> > be "absolute", as there are no larger ones. A depth filter, like the
> > Buon Vino pads, has a lot of different sized holes or channels, which
> > have an average, or nominal, size. As Tom points out, since there are
> > pores larger than the nominal size, there's a certain amount of larger
> > stuff that gets past. Just because the pads are rated .5 microns doesn't
> > mean they will stop everything of, say, one micron. <sigh> It takes a
> > better tool than a Buon Vino, I'm afraid. Even if one could contrive an
> > absolute filter for one, it probably wouldn't have the pressure to work.
>
> That covers the subject of pad filtration pretty well.
>
> > If anyone has found a way to do it, though, I'm all ears.
>
> You buy a 10" 0.45µ membrane cartridge, an Ametek (or equivalent) housing
> for it, some plastic fittings and hose. Hook the membrane cartridge in
> series with the output of the pad filter. Presto! Sterile wine. :^)
>
> Although membrane cartridges are expensive, you can re-use it many times
if
> the wine you run through it is well filtered to begin with.
>
> Tom S
>
>

Tom,

That's a great idea, but would my little BV minijet filter have the
power to push wine through both filters? I have my doubts.

Also, my batches tend to be pretty small, in the 5 gal range for whites.
Would the losses due to housing size, etc., be significant?

I actually built a 10' cartridge filter some years ago, but never used
it because it was oversized for my purposes. Perhaps as my newer vines
start producing closer to expected capacity (50 gal), it might pay to
get a set of cartridges.

Thanks, Mike MTM

Tom S wrote:


> You buy a 10" 0.45µ membrane cartridge, an Ametek (or equivalent) housing
> for it, some plastic fittings and hose. Hook the membrane cartridge in
> series with the output of the pad filter. Presto! Sterile wine. :^)
>
> Although membrane cartridges are expensive, you can re-use it many times if
> the wine you run through it is well filtered to begin with.
>
> Tom S
>
>