Interrelationships Between Marbling, Subcutaneous Fat Thickness and Cooked Beef Palatability

Abstract
Yearling and long-yearling steers (n = 471) were fed identical finishing diets for 100, 130 or 160 d at a commercial feedlot. The cattle were slaughtered, carcasses were evaluated by a USDA grader and rib steaks were cooked and used for sensory panel evaluation. Marbling had a low, but positive, relationship to all of the palatability traits of beef; more than 90% of the steaks with “slight” or higher degrees of marbling were “desirable” in overall tenderness, flavor desirability and overall palatability. The relationships between subcutaneous fat thickness and the organoleptic properties of beef were neither linear nor additive; fat thickness levels of 7.6 to 10.2 mm provided relatively high assurance of “desirable” palatability. Compared to marbling, fat thickness was ineffective as a predictor of cooked beef palatability and, therefore, would appear to be an unsuitable substitute for marbling. However, marbling, used in combination with a minimum subcutaneous fat thickness constraint of 7.62 mm for carcasses with a “slight” amount of marbling, facilitated more equitable stratification of carcasses according to their expected palatability than did marbling alone.