Mu Guk (Beef and Radish Soup)

Mu-guk (also spelled muguk) is soup with Korean radish as its main ingredient. Radish is prized in Korean cooking for two qualities: eaten raw in season it is crisp and sweet, and simmered it gives a broth what cooks call a siwonhan taste — clean and refreshing. The Encyclopedia of Korean Folk Culture notes that radish is generally thought to have arrived from China in the Goryeo period and spread from there into kimchi, salads, braises and soups.

The best-known version pairs radish with beef as a clear soup (malgeun-janguk) seasoned with soy sauce. Lee Yong-gi's 1924 cookbook Joseon mussang sinsik yori jebeop gives a clear soup of thin-sliced beef and blanched radish seasoned with soy sauce, green onion, garlic, pepper, sesame oil and sesame salt, stir-fried in the pot and then simmered long in water. The folk encyclopedia records other names for it, including sogogi malgeun-janguk and mu-hwangbokki-tang, from hwangyuk, an old word for beef.

Because radish keeps well through the winter, mu-guk turns up on the table in every season, though autumn and winter radishes are the sweetest. It is the kind of soup that rarely gets written about precisely because it is cooked so often.

• Low in calories, with protein from the beef; radish contributes potassium and some vitamin C, by the Korean food composition table.
• A light, mild soup that suits almost any meal and is easy to eat.

• Sogogi mu-guk: the standard clear beef version. For a clearer broth, some cooks simmer brisket whole, add large chunks of radish partway through and slice the meat afterward.
• Gyeongsang style: the folk encyclopedia notes that cooks in the southeast add gochugaru to the clear soup for a spicy, sharp version.
• Other partners: squid, ground perilla seed (deulkkae mu-guk), fish cake and mussels; the MFDS food database analyzes several of these separately.
• Cutting: flat squares (nabak-sseolgi) are standard; radish shaved like a pencil suits long simmering, and thin matchsticks suit the perilla version.