White peppercorns differ in considerably from black peppercorns in
appearance, aroma, flavor and even chemical composition. This is because
the fully ripe fruits of the pepper plant undergo retting, a process
that involves water soaking and subsequent rubbing to break down pulp
fibers and remove the outer skins. The final result is a smooth, white
peppercorn, which now consists of just the seed. This explains why the
spice lacks the pungency in taste and scent that black peppercorns
possess. Still, adequate levels of the piperine compound remain to
ensure a satisfactory level of spicy heat.
In the United States, black pepper far exceeds white pepper in popularity.
In northern Europe, however, the exact opposite is the case. In fact, 10
times more white pepper is sold in the region than black pepper.