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
Genovese sauce brought by Genovese immigrants or merchants, at a time when Genoa and Naples were two of Italy's most important ports. It could also be referring to its inventor's name, since Genovese is a widespread surname in Campania. Genovese sauce is now unknown beyond Campania. The sauce's use of onions may reflect a French influence, and resembles Boeuf à la mode. During the mid 19th century, ‘Salmon in Hollandaise and Genovese sauce’ was served in the Grand Véfour restaurant of the Palais-Royal in Paris as a luxury dish. Genovese sauce is not to be confused with Pesto from Genoa and Liguria,