RP says that he doesn't use black pepper anymore because it is fermented. I've been putting green peppercorns in my broth, figuring they might not be fermented. Decided to look it up and found this from The Spice House:
White, black and green peppercorns all come from the same vine. They grow in clusters (like grapes), and are harvested in various stages of growth. Green peppercorns are young when they are picked and dehydrated or preserved, with a resulting mild flavor. The black peppercorns are left on the vine to fully mature and develop a stronger flavor profile. White peppercorns are black peppercorns which have been soaked to remove the outer casing. This gives the white peppercorns a more intense flavor, with a slightly fermented taste and smell from the soaking process.
Pink peppercorns and Sichuan peppercorns are not true peppercorns. Pink peppercorns are soft, fragile berries with a sweet-sharp flavor. Sichaun pepper is the berry of the mountain ash tree, with a pungent, cold flavor instead of the usual heat of a peppercorn.