Napa cabbage

Napa cabbage (Brassica rapa subsp. pekinensis) is a member of the mustard family that originated in China. It is a biennial grown as an annual leaf crop, and in Korea it is counted, with radish, chili pepper and garlic, among the country's four essential vegetables.

Cabbage has a long written history on the peninsula: it is first recorded in Hyangyak gugeupbang, a thirteenth-century Goryeo medical text. The early plants did not form heads at all and grew loose leaves more like lettuce. Semi-heading "Joseon cabbage" types appeared in the mid-1800s, and local cultivars such as Gaeseong and Seoul cabbage became prized. The fully headed type now sold everywhere, known at first as ho-baechu ("foreign cabbage"), arrived from China around the turn of the twentieth century. Cooks initially found it tougher and less flavorful, but its higher yields won out: it became the market standard in the 1970s and, by the 1980s, the cabbage used for kimchi almost everywhere.

Cabbage is grown across South Korea, traditionally in the river valleys of the Han, Nakdong and Yeongsan. Production follows the seasons. Summer cabbage comes from cool highland fields in Gangwon Province, including farms at more than 1,000 meters around Anbandegi near Gangneung. Winter cabbage is grown in the warm far south, especially around Haenam in South Jeolla, where it stays in the field through the cold months and is harvested in spring.

Its central role is kimchi. Every late autumn, families and communities gather for kimjang, the collective making of large batches of kimchi to last through winter, a practice UNESCO inscribed on its Representative List of the Intangible Cultural Heritage of Humanity in 2013. An 1816 farming calendar already describes autumn kimchi-making from freshly harvested radish and cabbage seasoned with chili, garlic and ginger. Beyond kimchi, napa cabbage is simmered in soups, blanched for wraps, and dressed raw as geotjeori, a fresh, unfermented kimchi.

• Low in calories: Raw napa cabbage is mostly water and provides very little energy per serving.
• Vitamins: It is a source of vitamin C and folate, and also provides vitamin K.
• Fermented form: As kimchi it is a fermented food; research on the possible health effects of fermented vegetables is ongoing.
• Sodium caveat: Kimchi and salted cabbage are high in salt, so people watching their sodium intake should keep portions modest.