Im sorry to say, from passed experience, their is no cure, once a shit eater, all ways a shit eater, just one of them things.
I have in the passed tryd, pineapple, rock sulphur ect ect, nothing works..
Some pups do this a wee bit, but some, grow out of it, the out and out shit eaters eat any dog crap and still do when they have grown.
Hound breeds, greyhounds, whippets gun dog breeds seem more prone to it.
Im lucky, to have dogs that are not shit eaters at the moment.
Not a good thing to have in a running dogs, about to go coursing or lamping and its stomach full of dog crap..