I usually soak basmati rice for a half hour before cooking it.

The other day I took some calrose rice by mistake and started soaking it
before I realized it wasn't basmati.

I figured I would just use it the next time I made an Asian dish, and put
it in a jar with a lid. Then I forgot about it for several days.

Well, today I noticed it. Opening the lid I got some nice fermentation
smells. I drained the rice, added water, and cooked it.

It was foul, like a mixture of rice and some funky parmesan.