Black pepper
Roughly mashed black peppercorns
Black pepper is produced from the still-green unripe drupes of the pepper plant. The drupes are cooked briefly in hot water, both to clean them and to prepare them for drying. The heat ruptures cell walls in the pepper, speeding the work of browning enzymes during drying. The drupes are dried in the sun or by machine for several days, during which the pepper around the seed shrinks and darkens into a thin, wrinkled black layer. Once dried, the spice is called black peppercorn. Black peppercorn is considered spicier than white peppercorn.

 

White pepper
White pepper consists of the seed of the pepper plant alone, with the darker colored skin of the pepper fruit removed. This is usually accomplished by a process known as retting, where fully ripe peppers are soaked in water for about a week, during which the flesh of the pepper softens and decomposes. Rubbing then removes what remains of the fruit, and the naked seed is dried. Alternative processes are used for removing the outer pepper from the seed, including decortication, the removal of the outer layer from black pepper from small peppers through mechanical, chemical or biological methods.
White pepper is sometimes used in dishes like light-coloured sauces or mashed potatoes, where ground black pepper would visibly stand out. They have differing flavor due to the presence of certain compounds in the outer fruit layer of the drupe that are not found in the seed.

 

Green pepper
Green pepper, like black, is made from the unripe drupes. Dried green peppercorns are treated in a way that retains the green colour, such as treatment with sulfur dioxide or freeze-drying. Pickled peppercorns, also green, are unripe drupes preserved in brine or vinegar. Fresh, unpreserved green pepper drupes, largely unknown in the West, are used in some Asian cuisines, particularly Thai cuisine. Their flavor has been described as piquant and fresh, with a bright aroma. They decay quickly if not dried or preserved.

 

Orange pepper and red pepper
A product called orange pepper or red pepper consists of ripe red pepper drupes preserved in brine and vinegar. Ripe red peppercorns can also be dried using the same colour-preserving techniques used to produce green pepper. Pink pepper from Piper nigrum is distinct from the more-common dried "pink peppercorns", which are the fruits of a plant from a different family, the Peruvian pepper tree, Schinus molle, and its relative the Brazilian pepper tree, Schinus terebinthifolius. In years past there was debate as to the health safety of pink peppercorns, which is mostly no longer an issue.

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