What kind of meats are called sweetbreads?

Throat sweetbreads are the thymus gland and heart sweetbreads are the pancreas from either veal, lamb, beef or pork. They are milder flavored than other organ meats.

Sweetbreads are a calorie-dense food that is high in protein, fat, potassium and vitamin C. They require a lot of preparation before serving, which often keeps people from cooking them at home. Preparation includes a long soak time, blanching, and trimming of the membrane and vessels. The meat should then be pressed and chilled for a few hours before being sliced for cooking. Prepared sweetbreads are traditionally pan-seared, broiled or fried. Each method results in a crispy outside with a tender and moist inside.