Dry Aging

Dry aging is a technique for improving beef by hanging or racking whole cuts in a controlled environment for several weeks so they slowly lose moisture; as the meat dries, its flavor concentrates and its natural enzymes break down connective tissue, which tenderizes the meat. During this time particular molds, notably species of the genus Thamnidium, grow on the meat's exterior and are considered beneficial rather than spoilage, since the enzymes they produce further contribute to tenderness and flavor; the dried, moldy crust that forms is trimmed away before the meat is cooked. A typical dry-aging period of fifteen to twenty-eight days can cause the meat to lose a third or more of its original weight as moisture, which is a major reason dry-aged beef is expensive and found mainly at specialty butchers and upscale steakhouses rather than ordinary supermarkets.