The “Asiago” protected designation of origin “is reserved for the cheese, produced exclusively with cow’s milk, obtained in accordance with this specification. It is produced with milk from herds located in the defined area and by dairies located within the protection zone” (articles 1 and 2 of the DOP Asiago Product Specification).
It may seem obvious that cheese is produced with fresh, wholesome milk, but this is not always the case: various commercial dairy products may be produced from semi finished materials available on the global market, or through the addition of powdered milk products. This cannot happen with DOP cheeses, because all stages of production, from raw material to market-ready product, must comply with the rules handed down by tradition and specified within the production guidelines.
More informations here