Chopi (Korean Pepper, Zanthoxylum piperitum)

Two related shrubs grow wild in Korea, and their names are constantly confused. Chopi is Zanthoxylum piperitum; true sancho is Z. schinifolium. A 2019 study from the Jeonnam Institute of Natural Resources Research describes both as early-cultivated trees of southern Korea, used as spices and as traditional herbal medicines. One field mark separates them: chopi bears its thorns in opposite pairs, sancho alternately. Once the husks are dried and ground, they are hard to tell apart, and the study found that commercial products are often mixed. A Jeonbuk Ilbo article adds that cookbooks, broadcasts and even dictionaries call chopi 'sancho.' True sancho, also called bundi, is mainly pressed for oil, while chopi supplies the spice. The Korean Food Composition Table itself lists the powder as 'sancho,' and the folk encyclopedia's loach-soup entry writes 'chopi powder (sancho).'

The plant has many regional names: jepi in Gyeongsang, jaengpi or jompi in Jeolla, and jopi. The Daegu history and culture encyclopedia calls chopi a characteristic Gyeongsang ingredient. Young leaves are made into kimchi and jangajji, and the husks of ripe fruit are dried and ground. Before chili peppers arrived, the same source says, jopi powder was a heat-giving seasoning as well as an aromatic (see chili peppers in Korea). Daegu's jepi-kimchi, made with fresh leaves or with powder stirred into young cabbage kimchi, is also known as temple food at Donghwasa and other monasteries (see temple food). The same entry notes that the Annals of the Joseon Dynasty record ground jepi being used to stun fish, an early link between this spice and fish.

That link survives in chueotang, loach soup. The Encyclopedia of Korean Folk Culture describes the Jeolla style seasoned with 'sancho' for heat and the Gyeongsang style finished at the table with chopi powder, which tempers the muddy flavor of loach. Chopi also goes into spicy freshwater fish stews (maeuntang) and some kimchi. It is a quietly regional spice of the southeast (see Gyeongsang).

• A pinch-sized spice: Chopi is used by the pinch, so it contributes flavor rather than meaningful nutrition. No food-composition entry clearly identifies Z. piperitum: the Korean table lists only a 'sancho' powder, so nutrition is omitted here.
• Traditional medicine: In Korea and China, Zanthoxylum husks are traditional remedies for stomachache, intestinal worms and skin complaints. These are traditional uses; research on the plants is ongoing and does not establish them as treatments.
• Product authenticity: Researchers note that commercial chopi and sancho powders are often mixed or adulterated. Buy from trusted sellers, especially for herbal use.
• Numbing effect: The tingling can surprise first-time eaters and children. Start with a small pinch.