Are you saying you put cayenne pepper on a poop to keep him from eating it and he ate it, anyway? Oy, he must have a tongue of steal!
As long as you were out there to put pepper on it, why not just pick it up right away? That way he doesn't get a chance to eat it at all!
We have a couple of poop eaters here and the only
thing we've ever found to prevent it is to pick it up as soon as it's deposited...