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
Farmstead cheese Farmstead cheese Farmstead cheese, less commonly known as farmhouse cheese, is produced from the milk collected on the same farm where the cheese is produced. Unlike artisan cheese, which may also include milk purchased and transported from off-farm sources, farmstead cheese makers only use milk from animals they raise. According to the American Cheese Society, "milk used in the production of farmstead cheeses may not be obtained from any outside source". As a result, the cheeses produced often have unique flavors owing to the farm's local terroir. Most farmstead cheese is produced from cow, goat or sheep milk, although some