Piper nigrum L. (Piperaceae)



Piper nigrum growing in the Oxford Botanic Garden. Coloured plate of Piper nigrum from Curtis's Botanical Magazine (1832, t.3139).

Rare, highly desirable plant products command vast prices; a millennium ago, pepper was worth a fortune. Pepper, the hard, dried fruit of an evergreen, woody, southern Asian vine of tropical forest shade, is the most widely traded spice on the planet. The pepper trade between Europe and Asia extends into antiquity. Pepper was known to the Greek philosopher Theophrastus, and, by first century AD, Pliny bemoaned the drain on Roman coffers because of the money flowing into the hands of Indian pepper traders. When Alaric I threatened Rome in 408 AD, part of the ransom paid to prevent him sacking Rome was 3,000 pounds of pepper.

The tiny flowers of Piper nigrum, clustered together into long catkins, develop into small, bright red spherical fruits, tightly packed along the inflorescence. Until the gradual establishment of pepper plantations across the tropics from the late eighteenth century, pepper production was restricted to the Malabar Coast of India. Wild pepper has sexually reproducing, separate male and female plants; in contrast, cultivated pepper has asexually propagated, hermaphrodite plants.

Processing differences, and their effects on the pungent alkaloid piperine, produce black pepper (unripe fruits, briefly cooked then dried), white pepper (ripe fruits retted and cleaned) and green pepper (unripe fruits dried or pickled).

Pepper is common in its native Indian range, but acquired the cachet of European rarity because it was thought difficult to collect and transport. Pepper fascinated Europeans; it worked on olfactory senses in ways few native plants could. Pepper consumption became a status symbol; people wanted to show off that they could afford it. Governments taxed pepper, and an elaborate fiscal waltz between the excise and smuggler evolved as people tried to evade their liabilities. However, pepper established the wealth and power of Venice and drove Iberian exploration in the fifteenth century.

High value products attract criminals. Even in early nineteenth-century Britain, when pepper cost a mere fraction of what it had been in previous centuries, counterfeiters were at work. Black pepper corns were fashioned from linseed residue mixed with clay and chilli pepper, ground black pepper was sold mixed with pepper dust or an even more 'inferior sort of this vile refuse' called sweepings of pepper dust. Black pepper was even transmuted into white pepper by bleaching it with seawater and urine. Pepper once a currency and means of both storing and exchanging wealth is today a mere trifle; a peppercorn rent.

Further reading

Miller JI 1969. The spice trade of the Roman Empire. Clarendon Press.

Freedman PH 2008. Out of the east: spices and the Medieval imagination. Yale University Press.

Stephen Harris