óstyrkur

Óstyrkur is a traditional Icelandic dish that originates from the northern regions of the country, particularly the Westfjords (Vestfirðir) and the Westfjords Peninsula. The name "óstyrkur" translates roughly to "old cheese" or "aged cheese," reflecting its primary ingredient, which is fermented shark liver oil mixed with dried fish, typically dried cod or Greenland halibut. This dish is known for its strong, pungent flavor and is often considered an acquired taste due to its intense aroma and taste.

The preparation of óstyrkur involves fermenting the liver of Greenland shark (*Somniosus microcephalus*), which is rich in squalene and vitamin A. The liver is rendered into oil, which is then mixed with dried fish, salt, and sometimes other spices. The mixture is left to ferment for several months, developing its characteristic strong smell and flavor. The dish is typically served on rye bread or flatbread, often accompanied by butter or other dairy products to balance its intensity.

Óstyrkur is a staple in Icelandic cuisine, particularly in rural areas where it has been preserved as a traditional food source. It is often enjoyed as a snack or a side dish, though its bold taste makes it more of a specialty item. The dish has gained some international attention, particularly among adventurous food enthusiasts, though it remains a niche delicacy outside of Iceland.

The consumption of óstyrkur is not without controversy, as the Greenland shark is a slow-growing, deep-sea species with low reproductive rates. This has led to discussions about sustainable fishing practices and the ethical implications of harvesting the shark for its liver. Despite these concerns, óstyrkur remains a cultural symbol of Icelandic tradition and resilience.