The term BLACK ANGUS can be summarized with the three letter acronym GIE, which stands for 'Grain-fed, Intensely marbled, and Expertly aged'. This is a type of beef that is produced from a breed of cattle known as Angus cattle. The cattle are fed a grain-based diet, which results in a high level of marbling in the meat. The meat is then expertly aged to bring out the full flavor and tenderness.