Au jus the cook may simply skim off the fat from the juices left after cooking and bring the remaining meat stock and water to a boil. "Jus" can be frozen for six months or longer, but the flavor may suffer after this time. American recipes "au jus" often use soy sauce, Worcestershire sauce, salt, pepper, white or brown sugar, garlic, beets, carrots, onion, or other ingredients to make something more like a gravy. The American "jus" is sometimes prepared separately, rather than being produced naturally by the food being cooked. An example could be a beef "jus" made by reducing beef
Chaudfroid sauce Louis-Alexandre Berthier (20 November 1753 – 1 June 1815) of France, during Berthier's time under Napoleon. Chaudfroid sauce is a culinary sauce or gravy that can be prepared as a meat-based sauce by boiling the carcasses or bones of game meats or other meats such as poultry with herbs and spices. Vegetables such as onion and carrot have also been used. After cooking, the reduced sauce mixture is strained and gelatin is then added to provide viscosity. Chaudfroid sauce is used for several meats and meat-based dishes that are served cold, including meats such as fish, poultry, rabbit, venison, partridge,