One is, I don't use a pounder at all. I was taught to make Kimchi by a Korean friend. We just sprinkle salt throughout the cut cabbage and other veg, and leave it in a container for an hour or three, or overnight. Some brine comes out of the vegetables and they wilt, so then when we squash them into the fermenting container, there doesn't seem to be any need to pound them
Other thing is, sure, yeah, wash your new used pounder well like you'd wash any kitchen implement that you bring in from outside, maybe stir it in some boiling water if you feel nervous, and go ahead and use it! Sandor Katz's books and my subsequent experience made me feel very confident that as long as your ferment has mostly cabbage and a nice amount of salt, and is packed in roughly airtight, the desired bacteria will take over everything else and will almost always be fine. It might be different if there's sweet stuff or meat or something in there, but a standard veg ferment rarely goes wrong. We've been making it at our school every autumn since 2011, about 50 - 100 liters per year or kimchi or Ladakhi cabbage pickle, in less than perfect or sterile conditions, no airlocks, and we haven't had any failures except when we left it in the warm fermenting place too long.
Also, last year I resurrected some wooden mystery tool from the drawer in my kitchen, had a friend whittle it smooth, and have been using it for stirring sourdough twice a week ever since. It was certainly never sterile and still has a nail embedded in it, but the sourdough just knowns what it's supposed to do, and does it. No problem.
Works at a residential alternative high school in the Himalayas SECMOL.org . "Back home" is Cape Cod, E Coast USA.
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