Blue cheeses are known for their bold flavor, creamy texture, and distinctive blue-green veins created by the mold Penicillium roqueforti. Yet, not all blue cheeses are the same. The main difference among them lies in the type of milk used and where they are made. Roquefort, for instance, is produced from sheep’s milk, while Gorgonzola and most other blue cheeses are made from cow’s milk.
Roquefort cheese is a protected delicacy that can only be produced in specific regions of France, particularly in the caves of Roquefort-sur-Soulzon, where the natural environment provides ideal conditions for ripening. Authentic Roquefort must be aged in these limestone caves, where humidity and temperature promote the growth of Penicillium roqueforti, giving the cheese its characteristic sharpness and aroma.
Blue cheese, in general, can be made from raw, heated, or pasteurized milk—either whole or partially skimmed—with a butterfat content of about 3.5%. Cheesemakers often prefer raw or lightly heated milk because lipase, a natural enzyme, remains active. Lipase breaks down milk fat into fatty acids and glycerin, producing the rich, tangy flavors that define blue cheese. Pasteurization, while important for food safety, can inactivate this enzyme, slightly muting the complexity of the flavor.
When milk is used for cheesemaking, its temperature is first adjusted to around 85°F (29°C) and then homogenized to ensure even fat distribution. A starter culture of lactic acid bacteria is added and incubated at 90°F (32°C) to begin fermentation. Rennet, another enzyme, is then added to coagulate the milk. Within about an hour, the curds form and are cut into small cubes to separate them from the whey. After stirring and draining, salt is added to enhance flavor and control microbial growth.
The curds are then inoculated with Penicillium roqueforti, the mold responsible for creating the blue veins. The mixture is placed in molds and held at 65–68°F (18–20°C) before being transferred to cooler rooms for salting and aging. During ripening—typically two to three months—controlled humidity and airflow allow the mold to grow throughout the cheese, forming its signature marbled appearance.
As the cheese matures, its acidity increases, salt concentration rises, and moisture decreases—all of which limit unwanted microbial growth while intensifying flavor. Once fully cured, the cheese is cleaned, cut into wedges, and wrapped for sale. The result is a complex, flavorful product that combines craftsmanship, biology, and centuries of tradition in every bite.Understanding the Craft of Blue Cheeses: Roquefort, Gorgonzola, and Beyond
