I like the gourmet whole pepper blends with the white, black and red peppercorns in them.  What makes them different colors?

--Anita

White, black and green peppercorns, which are also included in some mixes, are all from the same plant, piper nigrum, which is a climbing vine native to parts of India and the Far East.  Peppercorns grow in small clusters on the vine, similar to grapes.  The color depends on the ripeness of the berry when it is picked, and how it is processed.

The pungency is from a chemical called piperine which is found in a thin layer of fruit between the skin and the pepper seed, and on the surface layer of the seed itself.

Green peppercorns are under-ripe when they are picked and dried.  They may be treated with sulfur dioxide or freeze-dried to help preserve the green color.

Black peppercorns are a more mature, but still unripe berries.  The berries are briefly parboiled to release browning enzymes that cause the color change, and then dried either naturally or in mechanical driers.

White peppercorns are the ripe berries of the plant, which are soaked to soften the skin and outer fruit, which are then rubbed off leaving the bare seed.  The seed is dried similar to black pepper.  Because the fruit layer is removed, some of the piperine is lost, making white peppercorns less pungent than black ones.

Of the four colors, the red or actually pink peppercorns are the exception, since they don't come from the same plant.  Pink peppercorns are the berries of the Brazilian pepper tree, schinus terebinthifolius, and not a true peppercorn.  The tree is in the same family as the cashew.  Like green peppercorns, the pink berries are picked under-ripe and then freeze-dried or treated to retain their color.