Blue Vein is a general term used to describe cheeses made from the Penicillium Roqueforti bacterium which is a blue mould that grows on either the surface or inside the cheese.
Britain’s Stilton, France’s Roquefort and Italy’s Gorgonzola are all types of blue mould-ripened cheese. They can be made from sheep or goat’s milk but are most commonly produced using cow’s milk.
The exact origins of blue cheeses are unknown but it’s believed they were accidentally discovered at a time when cheeses were stored in caves. Roquefort is thought to date back to approximately 79 AD while Gorgonzola is first mentioned around 879 AD, although the distinctive blue veins in the cheese were a later addition, around the 11th Century. In comparison, Stilton is a newcomer appearing in the early 18th Century.
The flavour depends on the type of blue cheese made including its shape, size, curing conditions and maturity. However, all blue cheeses tend to have a sharp, salty taste and should have a creamy texture.