Many people think that sweetbreads are culinary code for calves’ brains.
But the term sweetbreads is actually a benign-sounding pseudonym for the paired thymus glands and pancreas of milk-fed veal or calves. (You can also find inferior pork or lamb sweetbreads if you look hard enough.) The rounder pancreas gland near the heart is more prized than the tubular thymus throat gland. The pancreas gland has a more delicate flavor and smoother texture.
If you’re shopping for sweetbreads, be sure that they’re still snow white, fleshy and firm to the touch. Rinse them in several changes of acidulated water before using. Once you get them home, don’t keep them for more than 24 hours in the refrigerator. Sweetbreads are normally blanched, refreshed in cold water and cooled before being braised, poached, sautéed, fried, broiled or blended into a soufflé, pâté or filling.