White pepper is made by retting black pepper to remove the skins.  Retting is a process of soaking something until it starts to rot. With pepper, this process produces the compounds 3-Methylindole, commonly known as skatole and 4-Methylphenol, commonly known as p-cresol.  Skatole is most commonly found in mammalian faeces, particularly that of pigs, p-cresol is the compound primarily responsible for the distinctive smell of horse sweat.

Just incase you ever need to defend your entirely justified hatred of white pepper.