Raw milk has not been heated in the transformation from milk to cheese. Without pasteurization, beneficial microbes flourish and the cheese exhibits many different flavors and notes, which are less homogenous than in pasteurized milk cheese. Using raw milk is a timeless tradition in Europe, and many important DOP cheeses require the use of raw milk even today. In order to be imported into the U.S., raw milk cheeses must be aged at least 60 days, according to the FDA, but in Europe, the same limits do not apply.