Whisky Scotch whiskies are generally distilled twice, although some are distilled a third time and others even up to twenty times. Scotch Whisky Regulations require anything bearing the label "Scotch" to be distilled in Scotland and matured for a minimum of three years in oak casks, among other, more specific criteria. Any age statement on the bottle, in the form of a number, must reflect the age of the youngest Scotch whisky used to produce that product. A whisky with an age statement is known as guaranteed age whisky. Scotch whisky without an age statement may, by law, be as young
Barrel the much lower cost. Sherry is stored in casks made of North American oak, which is slightly more porous than French or Spanish oak. The casks, or butts, are filled five-sixths full, leaving "the space of two fists" empty at the top to allow flor to develop on top of the wine. Sherry is also commonly swapped between barrels of different ages, a process that is known as Solera. Laws in several jurisdictions require that whisky be aged in wooden barrels. The law in the United States requires that "straight whisky" (with the exception of corn whisky) must be stored