Gorgonzola is made exclusively with milk from cows raised in Piedmont and Lombardy. Since 1996, Gorgonzola has benefited from the Denomination of Protected Origin (DOP) certification.
Gorgonzola is made by heating the milk to 82°-93°F, adding milk enzymes, mold (penicillium) and rennet. After the curd is broken, the cheese mass is left to rest and then lifted out with hemp cloth and left to drip-dry for 12 hours. The cheese is ripened for 5 to 6 days and turned daily. It is salted by hand every other day for 3 weeks.
Copper or steel rods are inserted into both the top and bottom of the cheese over the course of 4 to 5 days, allowing for mold to develop. The cheese is then aged for 20 to 30 days in a room with 80% humidity and 43°-50°F.
At the end of this process, the cheese will have developed its characteristic blue-marbled color and sweet, yet slightly spicy, flavor.