On a whim one day after looking through a cabinet and finding a bag of uncooked rice, I opened the bag and poured it in to my old (stinky) kayaking shoes.
A couple of days later I picked one up and it was bone dry and did not smell at all.
They have entered their "dormant"
stage. Just add water to bring the smell back.
Soak them in Mirazyme to get the stink out.
Jim
How did the rice taste?
a bit cheesy
kind of like parmesan with a hint of toe jam 
Cheap stink fix
Soak in vinegar and water - works great (i do an overnight soak)
Persistent Stink
I soaked some stinking Tevas in vinegar for a few hours and it didn’t help much. Much better results with an overnight soak but what worked best was some woolite and a bit of scrubbing. Sometimes those bugs are hard to kill.
newspaper
A piece of newspaper stuffed loosely in each boot does the same thing as the rice - acts as a desicant to dry them quickly, so the stink can’t brew.
The newspaper acts like a wick and dries out boots or gloves overnight, and then you store them dry, and (fairly) stink free.
Don’t waste money on Mirazyme…
…“Sink the Stink” or similar products. None of them do anything that rinsing and THOROUGHLY drying your shoes between uses won’t do. As others have suggested vinegar can be used to combat odors, as can a mild bleach solution. However, prevention is the best method. The three keys to preventing shoe odor are:
1 - Wear socks in your paddle shoes. The socks absorb sweat and skin oils, and help to keep dead skin cells out of your shoes. These are the things that the odor-producing bacteria feed on. The difference that this alone can make is startling.
2 - Rinse your shoes after EVERY use to remove any of the above that does get into them.
3 - Dry your shoes COMPLETELY after every use. The best way is to leave them in the sun to dry. Packing them with newspaper for a few hours helps speed the process if sun drying isn’t an option. Air drying after the paper is removed will complete the process.
sunshine helps also
I put shoes out in the sun to dry, the smell seems to get baked out of them.
Can’t do the same for the wetsuit, but prompt rinsing and a vinegar/water bath every so often does the trick.
Yeah
The Newspaper works … !!!
Fabric softner dryer sheets
will get the smell out once the shoes are dry.
^^ great response there
Doing that my assorted little booties are in their 3rd season, look like new and never stink. And I never use Sink the Stink, Mirazyme or similiar products. Using even a slim sock makes a big difference to trap skin cells and assorted foot funk.
Don’t put them in the car
I don’t put my paddling shoes in the car. they get attached to the Stearn of the canoe with a carabiner to a small loop of rope I have on the rear most thwart on all my canoes.
They are generally dry and not so foul when I get home, and tend to keep tailgaters away.