Blue cheese of blue veins. The distinctive flavor and aroma of blue cheese arises from methyl ketones (including 2-pentanone, 2-heptanone, and 2-nonanone) which are a metabolic product of "Penicillium roqueforti". These compounds are not formed in other types of cheese fermented by bacterial acidification alone. In the European Union, many blue cheeses, such as Cabrales, Danablu, Gorgonzola, Roquefort and Blue Stilton, carry a protected designation of origin, meaning they can bear the name only if they have been made in a particular region. Similarly, individual countries have protections of their own such as France's Appellation d'Origine Contrôlée and Italy's Denominazione di Origine
Blue cheese dressing Blue cheese dressing Blue cheese dressing is a popular salad dressing and dip in the United States. It is usually made of some combination of blue cheese, mayonnaise, and either or all buttermilk, sour cream or yogurt, milk, vinegar, onion powder, and garlic powder. There is a blue cheese vinaigrette that consists of salad oil, blue cheese, vinegar, and sometimes seasonings. Most major salad dressing producers and restaurants in the United States produce a variant of blue cheese dressing. It is commonly served as a dip with Buffalo wings or crudités (raw vegetables). Separation of water and oil (instability of