If the meat and bones are well cut and broken, the juices ought to be all extracted, with proper cooking, in three or four hours.  Longer cooking will render the stock thicker and more gelatinous but not more nutritious, and too long cooking will detract from its flavor.  As soon as the meat will fall from the bones, the stock should be removed from the pot and strained at once.

A good way to strain stock is to place a colander over an earthen crock or jar (the colander should fit inside the jar), with a cloth strainer within the colander.  Then dip the contents of the stock kettle into the colander, and leave it there to drain for fifteen or twenty minutes.  Do not squeeze the cloth, and when well drained, throw the scraps away.

[Illustration:  Arrangement for Straining Stock.]

French cooks, with their propensity for economy, sometimes select a good quality of beef, cook it so as to retain a portion of the juices in the meat, and make it serve both for preparing the soup and for boiled beef on the bill of fare.  The meat is not cut up, but is heated quickly and removed as soon as tender, so that only part of the juices are extracted.

Set the stock where it will become cold.  The more rapidly it cools, the more delicate will be its flavor, and the better it will keep.  The fat will rise to the surface, and can be easily removed when desired.  If the quantity of fat in the material used was considerable, a solid cake will cover the top.  This fat, by excluding the air, helps keep the stock sweet, and should not be removed until the stock is needed.

If only a portion is to be used at one time, the remainder with the fat should be reheated and cooled, that a new crust may be formed.  In winter, stock may be kept several days, if care is thus taken to reheat it.  In summer, unless kept in a very cold place, it will spoil in a few hours.

Soup should never be greasy, and hence, before using the stock, every particle of the fat should be removed.  To accomplish this, loosen the cake of fat from the dish with a knife, and if solid, it will sometimes come off whole; if soft, remove all that is possible without cutting into the stock, and afterwards wipe the top of the jellied stock with a cloth wrung out of very hot water, which will readily absorb any lingering portion of fat.  If the stock is not jellied, skim off all the fat possible, and then turn the stock through a napkin wrung out of ice water.  This will harden the grease, which will adhere to the napkin.  It is always better to prepare stock long enough before it is needed to allow it to become perfectly cold; if, however, it is necessary to use the stock very soon after it is prepared, the fat may be quickly hardened by turning the stock into a dripping pan or some other shallow dish, and placing it on ice in a cool place; if there is no time for this, strain several times through a napkin wrung out of ice-cold water, removing the particles of fat each time and wringing the cloth anew before straining again.  A little cold water poured into hot stock will also cause the grease to rise so that it can be easily skimmed off; but this method weakens the stock.