Boiling down whey 10:1 to create a brown, cheesy spread (such as the Norwegian prim and Swedish messmör) has been common in the Scandinavian countries for at least 2,500 years. An archeological find from September 2016 in central Jutland has determined that a cheese residue on pottery from circa 650 B.C.E. is a type of cheese, potentially similar to brunost.
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