Sichuan pepper is one of the spices in the five-spice powder popular in Chinese cuisine. It comes from the outer peel of berry fruit and is locally known as “hu jiao.” The earliest references to the Sichuan pepper, also called Schezuan pepper, are seen in the Classic of Poetry, said to have been compiled by Confucius (551-479 BC).
Sichuan pepper comes from several species of Zanthoxylum. These species are distributed across China, Nepal, Bhutan, Japan, Korea, Indonesia, and India. An allied species, Zanthoxylum americanum, is found in North America.
Z. americanum is a North American species, colloquially called the toothache tree, because of its anesthetic properties that the Native Americans used to relieve a toothache.
The pepper was used in China as a medicinal herb for seasoning. In ancient China, the pepper was steeped in wine to give it a unique peppery, lemony flavor. Avicenna (c. 1020 AD) referred to the spice as fagara. The spice came to the Persian and Arabic regions with traders who took the Silk Route from China to the region.
Sichuan pepper crop is a popular agroforestry non-timber forest product. Harvesting the berries is done when the fruit is ripe, as early harvesting exposes it to fungal infections and renders the production unusable.
The Sichuan pepper tree bears small reddish-brown berries that release round black seeds when split open. The texture of the seeds is like sand and is discarded. The outer coat of the berry is dried and used as a spice. Whole berries or ground into powder can also be used as a spice.
The pungency of Sichuan pepper comes from pungent alkamides stored in the pericarp. Alkamides are absent in the seeds. The lack of standardization and absence of collection, storage, and logistics protocols in the collection and processing has often led to health concerns raised by the major spice-importing countries of Europe and the US.
The import of Sichuan pepper was banned in the US in 2005 to protect the orange crop from citrus canker disease from infected peppercorns. Untreated berries carrying the bacteria Xanthomonas axonopodis can have a disastrous effect on citrus crops.
Bacteria contained in Sichuan pepper are killed when berries are gently roasted, a traditional practice. Imports into the US were re-opened but only for heat-treated peppercorns. Limited Chinese peppers are imported into the US, mainly for consumption by Chinese eateries and lovers of Chinese food.
Sichuan pepper, known locally as timur in Nepal, is exported mainly to India. In Nepal, spice trees are cultivated as an agroforestry species. The crop is raised on degraded forest and non-forest sites in the country. It is estimated that Nepal annually exports 850 to 1,100 metric tons of this spice to India, mostly raw.
Food
Oil infused with roasted peppercorns and mixed with salt and other condiments are popular in Chinese and East Asian cuisine. Some of this oil-based peppercorn product is exported to France, Italy, and other West European countries. Leaves of these trees are also used to flavor food in China.
Different species of Zanthoxylum have their distinct flavor. Z. alatum is spicy, and Z. avicennae and Z. schinifolium are anise-like in flavor. Most species have a lemon-like odor with warm and woodsy overtones. Z. piperitum leaves have a fresh flavor that lies between the mint and the lime.
Bacteria contained in Sichuan pepper are killed when berries are gently roasted, a traditional practice. Imports into the US were re-opened but only for heat-treated peppercorns. Limited Chinese peppers are imported into the US, mainly for Chinese eateries and lovers of Chinese food.
Additional reading:
- Asian Herbs and their wondrous health-giving properties
- Holy Herbs- Modern Connections to Ancient Plants