"Tom S" > wrote in message
om...
:
: "Glen Duff" > wrote in message
: ...
: > I've been using barrels for years and don't recall the problem in the
: > past, at least not as much as it's become in the past few years. I've
: > been getting a lot of mould around the bung in my two barrels and it
: > develops between weekly top ups. I generally wrap a paper towel soaked
: > in sulfite around the bung but even that does not seem to work.
: >
: > My main concern is that it requires some careful clean up both before
: > and after removing the bung each time I top up.
: >
: > Any suggestions.
:
: Clean the area around the bung as you have been doing, do your tasting and
: topping, and just before inserting the bung dip the business end of it
(the
: tapered part too) into dry sulfite powder. When you insert the bung it'll
: grind fresh sulfite into the wood at the bunghole. This works well with
: silicone bungs.
:
: BTW, are you sure your sulfite is still active? Exposure to air *rapidly*
: degrades potassium metabisulfite into potassium sulfate, which is
completely
: worthless. I can't stress this strongly enough. You should buy fresh
every
: year from a source that has a _lot_ of turnover, and sells the stuff in
: sealed foil bags. Home winemaking shops are not necessarily a good source
: for this. I buy mine from The Wine Lab, and even they say that their
stuff
: assays typically ~50% available SO2. Theoretical is 57%, but you're never
: going to get it that pure.
:
: Tom S

I had almost the exact same thing happen to me a number of years ago. Left
a paper towel around the bung to soak up some spilled wine and came back a
week later to a moldy mess. Getting rid of the mold in the wood turned out
to be a challenge and I am pretty sure part of the problem was the old
sulfite I was using at the time. Which raises an on going issue for me.
How do I ever know what "true" sulfite levels are in my wine? I find that
the titret measurements are so far off, to almost being useless. For
example, I keep notes on all my sulfite additions yet it isn't unusual to
record 35-40ppm with the titret six months after pressing even though I only
added 10-20ppm just before fermentation. On the other hand, I recently
measured a commercial white wine (recent vintage) and found only 8ppm.
Maybe the commercial wine doesn't use a lot of sulfite, but I don't
understand a mysterious doubling of sulfite in my wine. IIRC David Breedan
had suggested that titrets measure approximately 10-15ppm more than is
actually present, which makes me wonder why I even use them sometimes!
Combined with inherent error measurement it seems to become somewhat of a
guessing game as to your true sulfite levels.

To me this is an important issue because I am constantly topping up barrels
so I need to keep the sulfites up (for the periods between top ups). So
what do others do? New sulfite every six months and keep good notes or rely
on titret measurements?

Thanks for your opinions,
Tim, Vancouver