mold on wooden press slats?

not a fun situation there.

If the wood slats are varnished, then surface scrub with potash (potassium hydroxide) will probably be enough. If bare wood or oiled wood, then spores will be into the wood, and you'll probably have to boil the wood in chemical solution to kill the deeper spores.

I'd prefer not to do a bleach/soap scrub like one does on houses, because of potential for TCA formation. See above for my first choice if you have to boil (potash). Another good fungus attacker is super shock non-chlorine/non-bromine cleaner like used for spa tubs. Could also boil in peroxycarb (blend of sodium carbonate and sodium percarbonate) or lye (sodium hydroxide). I prefer to minimize sodium-based cleaners on wood exposed to the wine. Peracetic acid also good strong cleaner and doesn't contain sodium.

Prolonged ozone exposure will do it too, but you'd not do that in an enclosed place like ur house or garage.

All the above require care for your safety.

UV lamps will kill surface mold too, but may not catch all the spores in the wood.

When you are done killing the mold, you'll probably want to condition any bare wood surface; grapeseed oil is good for that. The mold killing will have aged the wood surface.

What other good treatments have others to offer?

Gene

P.S. in the future you might think about sun-drying your press after washing, so you don't put it away damp.

My press has varnished slats, so mold isn't really a problem for me. You might consider taking apart the basket and doing a sanding and varnishing on the wood.

Failing that, blast the thing with hot water, scrub it with sulfite solution and blast again with hot water before you use it next time. That won't remove _every_ trace of mold, but it'll knock down the population considerably.

Remember, your grapes come in from the field with all sorts of stuff on them, including mold spores. That's why you use sulfite in the wine and keep head space to a minimum. It creates an environment that the mold can't propagate in, so whatever spores are there will eventually settle out with the lees or be filtered out.

Tom S

I agree with Tom. Mold spores are present on grapes anyway.

Scrub them clean, you can use PBW, One-step or oxyclean (they are all the same thing sodium percarbonate) which will "bleach" out a lot of the mold and kill the live cells.

Really, the reason mold does not grow in wine anyway is the fact that yeast grow so much faster using up all the nutrients and after racking, there is not enough oxygen for mold to grow. Mold is a strict aerobe. That is why canning works. Canning does not so much kill mold (which it does but that is secondary), canning removes all the oxygen from the package, preventing mold spores from growing.

Whichever way you decide to disinfect, I'd recommend that afterwords you varnish (or re-varnish) the wood slats.

Is there any particular varnish better for this application?

any polyurethane varnish will work. You could look for a marine varnish...tough stuff.

Thanks Everyone!!!

Rob

Sealing wax. Quite a few years ago I bought a used press that had been neglected, it had been left out in the weather for some time. The slats were completely devoid of varnish. I simply painted the slats with hot sealing (parafin) wax. The wax soaked into the outer layer of the timber and sealed the surface very well. The basket is very easy to clean/sanitise and I looks as if the one application of wax will last a very long time.

WARNING. Be extremely careful when handling very hot sealing wax, it can burn and it will spatter ( like hot cooking ol) if water drops into it.

I didn't have the problem of mould. Howerver, I would scrub the afffected slats, treat the slats with SO2 as others have suggested on this NG and allow them to dry for a week or two before sealing the surface.

Regards Ian

I used Man-O-War.

Tom S