There was a mention of a footbed cleaner on the internet but I am unable to locate that in CH - anyone found it?
Have you tried putting them in the sun for a couple of hours?
Perhaps you can find the product you need at a nearby shoe store.
However it's a the bacteria in the foot bed living off the sweat that causes the smell - not dirty feed!
Actually bicarbonate of soda and tea tree oil is working But there was an official cleaner at some point
Seriously, the BODY SHOP has some very good products to prevent foot odour which can happen to anyone (except me of course) there is a scrub and a spray...they have no real parfum so are great for men and women, they smell a bit minty (ahh freshness)...They are pretty good, I gave these to my mom whose feet smell like doritos
Slightly OT, but a few years ago, on a Greyhound bus holiday in WA, the wife and I arrived at our backpackers in Broome, and boy did my trainers reek of putrefaction. The wife 'suggested' that they remain on the balcony overnight, as the smell was making small children cry. Early the next morning, I awoke to hear some thumping on the balcony. I opened the door just in time to see an aboriginal youth jump off the balcony and leg it with my trainers in his hands. I strongly suspect he quickly regretted his thievery, and now goes by the tribal name of 'He who walks alone', or 'He who must never be approached from downwind'.
Cheers
Jim