When brought from the market they may be put aside, in a tightly closed pail, or in a paper bag, in a cool, dry place.

By thus excluding the air they will keep fresh several days.

A short time before serving put them into ice-cold water to which a slice or two of lemon has been added.
=How to Cook Sweetbreads and Brains.= Remove the thin outer skin or membrane and soak in cold water, changing the water often, an hour or more.

Cover with salted boiling water, acidulated with lemon juice and flavored with vegetables, and cook, just below the boiling-point, twenty minutes.

They are then ready for preparation in any of the ways mentioned.