Fresh fish rapidly deteriorates unless some way can be found to preserve it. Drying is a method of food preservation that works by removing water from the food, which inhibits the growth of microorganisms.
Open air drying using sun and wind has been practiced since ancient times to preserve food. Water is usually removed by evaporation (air drying, sun drying, smoking or wind drying) but, in the case of freeze-drying, food is first frozen and then the water is removed by sublimation.
Bacteria, yeasts and molds need the water in the food to grow, and drying effectively prevents them from surviving in the food.
Fish are preserved through such traditional methods as drying, smoking and salting. The oldest traditional way of preserving fish was to let the wind and sun dry it.
Drying food is the world’s oldest known preservation method, and dried fish has a storage life of several years. The method is cheap and effective in suitable climates; the work can be done by the fisherman and family, and the resulting product is easily transported to market.
History
Salt cod has been produced for at least 500 years, since the time of the European discoveries of the New World. Before refrigeration, there was a need to preserve the codfish; drying and salting are ancient techniques to preserve nutrients and the process makes the codfish tastier.
The Portuguese tried to use this method of drying and salting on several varieties of fish from their waters, but the ideal fish came from much further north.
With the “discovery” of Newfoundland in 1497, long after the Basque whalers arrived in Channel-Port aux Basques, they started fishing its cod-rich Grand Banks.
Thus, bacalhau became a staple of the Portuguese cuisine, nicknamed Fiel amigo (faithful friend). From the 18th century, the town of Kristiansund in Norway became an important place of purchasing bacalhau or klippfisk (literally “cliff fish”, since the fish was dried on stone cliffs by the sea to begin with.)
Since the method was introduced by the Dutchman Jappe Ippes in abt 1690, the town had produced klippfisk and when the Spanish merchants arrived, it became a big industry.
The bacalhau or bacalao dish is sometimes said to originate from Kristiansund, where it was introduced by the Spanish and Portuguese fish buyers and became very popular.
Bacalao was common everyday food in north west Norway to this day, as it was cheap to make. In later years it is more eaten at special occasions.
This dish was also popular in Portugal and other Roman Catholic countries, because of the many days (Fridays, Lent, and other festivals) on which the Church forbade the eating of meat. Bacalhau dishes were eaten instead.