Lutefisk

About Lutefisk

Lutefisk (lutfisk) (pronounced [lʉːtəfɪsk] in Southern Norway, [lʉːtfɪsk] in Central and Northern Norway, Sweden and the Swedish-speaking areas in Finland (lipeäkala in Finnish)) is a traditional dish of the Nordic countries made from stockfish (air-dried whitefish) or dried/salted whitefish (klippfisk) and soda lye (lut). Its name literally means "lye fish", because it is made with caustic soda or potash lye.

Lutefisk is made from air-dried or salted/dried whitefish (normally cod, but ling is also used), prepared with lye, in a sequence of particular treatments. The watering steps of these treatments differ slightly for salted/dried whitefish because of its high salt content. The first treatment is to soak the stockfish in cold water for five to six days (with the water changed daily). The saturated stockfish is then soaked in an unchanged solution of cold water and lye for an additional two days. The fish will swell during this soaking, attaining an even larger size than in its original (undried) state, while its protein content decreases by more than 50 percent, producing its famous jelly-like consistency. When this treatment is finished, the fish (saturated with lye) has a pH value of 11–12, and is therefore caustic. To make the fish edible, a final treatment of yet another four to six days of soaking in cold water (also changed daily) is needed. Eventually, the lutefisk is ready to be cooked.

In Finland, the traditional reagent used is birch ash. It contains high amounts of potassium carbonate and hydrocarbonate, giving the fish a more mellow treatment than would sodium hydroxide (lyestone). It is important to not incubate the fish too long in the lye, because saponification of the fish fats may occur, effectively rendering the fish fats into soap. The term for such spoiled fish in Finnish is saippuakala (soap fish).