Good fresh brains are firm-looking, the form cleanly and symmetrically defined, the surface moistly glistening in aspect; they are white with a pearl cast, only the filigree network of thread-like veins in the surface membrane showing red. These conditions are not always met—otherwise good brains are often discolored by blood clots. In any case, those whose form and whose superficial cannular structure are ill-defined, the surface dull and messy in appearance, should be rejected.
Brains should be put to soak in cold water and the vein-threaded surface membrane carefully peeled off; it often facilitates the work to dip them repeatedly in water while removing it. Usually, with healthy-looking, firm, fresh brains, it slips free with little difficulty, but, occasionally, it offers frustrating and sometimes insuperable resistance; if after further soaking, it refuses to come free, leave it . . . Brains that have been badly bloodstained should be soaked again for 1 hour or so with several changes of water in order to draw from them the maximum discoloration (in professional kitchens, they are often parboiled to hasten the work of peeling, a process which, although permitting the membrane to be removed more easily, firmly stamps the flesh with a brown color and a muddy flavor that detracts greatly from their delicacy).