Sous-vide is a method of cooking food sealed in airtight vacuum plastic bags in a water bath for longer than normal cooking time: up to 72 hours under strict control. The intention is to allow the item to cook evenly, and thereby ensure a juicier food. These precooked food items-often in portion sizes-are reheated in special containers. The sousvide method has been in industrial operation since the 1960 and was introduced to restaurants in 1974. The advantage for restaurants and hotels is that they can operate a large menu with limited numbers of trained staff. There is lower waste, and the quality is considered to be vat a fully acceptable level.