Mackerel

Godeungeo is the chub mackerel (Scomber japonicus), a spindle-shaped fish about 40 cm long with a green back marked by black wavy lines and a silvery belly. It prefers water of roughly 10–22 °C and migrates around the peninsula: schools arrive off Jeju in late winter, move north up both the east and west coasts, and return south in autumn.

Mackerel has a long history in Korean waters. The 15th-century geography in the Sejong sillok lists it as a product of Hwanghae and Hamgyeong provinces, and later gazetteers add Gyeongsang, Jeolla and Gangwon. Jeong Yak-jeon's 1814 fish guide Jasan eobo calls it byeongmuneo, gives godeungeo as its common name, and describes fishermen luring it with fires at night, since the fish is drawn to light. In the Joseon period mackerel was split down the back and salted for sale, and its salted guts were prized as jeotgal.

Salting made mackerel a fish of the interior. In Andong, a landlocked city in North Gyeongsang, gan-godeungeo — mackerel gutted, packed with coarse salt, and sold in nested pairs called a son — arrived over days by road from the coast at Yeongdeok or by river up the Nakdong. Once a luxury, it became an everyday and ritual food there; refrigeration lowered its saltiness from the 1970s, and a vacuum-packed Andong brand was launched in 1999.

Fresh or salted mackerel is grilled as godeungeo-gui or braised as godeungeo-jorim, often over radish or aged kimchi, and simmered in stews.

• Omega-3 fats: Mackerel is an oily fish, and the Korean Food Composition Table lists nearly 3 g of omega-3 fatty acids per 100 g of raw fish, most of it DHA, along with protein and vitamin B12.
• A lower-mercury choice: The FDA and EPA list Pacific chub mackerel — the species sold as godeungeo — among their 'Best Choices' for low mercury. (King mackerel, a different fish, is on their list to avoid.)
• Salt in salted mackerel: Gan-godeungeo and other salted fish add sodium, and braising sauces add more; rinsing and portion size matter.
• Fish allergy: Fish is a major food allergen, and fish broths and sauces carry the same allergen.