Passing and straining sauces

Passing and straining belong to the codified kitchen of the nineteenth century, when Escoffier's Le Guide Culinaire and the brigade system made a sauce's smoothness a mark of the cook's training. Jacques Pépin — Complete Techniques carries the gesture into the modern teaching of method, setting out the sieve, the chinois and the cloth as tools to be chosen for the sauce in hand. The technique sits within the tradition of the fonds and the mother sauces, where every preparation is finished by passing before it reaches the plate.

Passing is the separation of a sauce, stock or purée from its solids by forcing or letting it run through a perforated or woven barrier. The conical chinois, fine and coarse, is used for stocks and sauces, the drum sieve (tamis) for purées and forcemeats, and damp muslin or étamine for the clearest results, as in a consommé or a velouté finished with fine texture. A coarse strainer removes bones and vegetable trimmings; a fine chinois removes particles and skin; the cloth removes what remains in suspension. The sauce is pressed with the back of a ladle where body is wanted, and left to drip where clarity is wanted.

A passed sauce is served with roasts, poached fish, poultry and vegetables, where its smoothness supports the main ingredient without competing with it. It is drunk with wines matched to the dish rather than to the sauce, a white Burgundy for a velouté of poultry or a Loire red for a reduced veal jus. The structural reason is texture: a sauce free of fragments coats the palate evenly, so its acidity, fat and concentration are read as a single clean line.