The desired texture of a mousse depends on its intended use. A mousse formed into a mold, chilled, and then turned out onto a plate as a freestanding item must be firm enough to hold its shape. Mousses packed into oblong terrine forms, chilled, and then sliced must be quite firm. When used in hors d’oeuvre work, mousses used as a filling for pastry shells or canapé bases should be soft enough to be piped from a pastry bag.
Another factor to consider is the temperature at which the mousse will be served. If intended as an Ă la carte appetizer, plated to order, a mousse can have a softer texture than one that must sit on a buffet table at room temperature for several hours.