The objective of this study was to update the existing nutritional data available in the USDA National Nutrient Database for Standard Reference by providing revised nutritional information on the round and loin cuts evaluated in Phase III of the Nutrient Database Improvement Project. A total of 20 carcasses were selected from three packing plants across the United States, and round and loin subprimals from these carcasses were collected and transported to Texas A&M University. These subprimals were fabricated 14 to 21 d postmortem, dissected either raw or cooked, and divided to determine the amount of separable lean, separable fat, and refuse amounts per cut. Separable lean from these cuts was homogenized and proximate analyses were conducted in order to determine percent total chemical fat, protein, moisture, and ash.
Cooking yields and fat retention values were determined for the cuts that were grilled and roasted. Cuts with external fat had higher cooking yields than cuts with external fat removed. Cuts with external fat had higher fat retention values than the cuts with no external fat. Dissection data indicated that cuts trimmed to lower levels of external fat had the highest values for percent lean and the lowest values for percent seam and external fat and bone-in cuts had the lowest values for percent lean and the highest values for percent refuse. Proximate analyses indicated a decrease in percent moisture as the percentage of total chemical fat increased. Also, round cuts evaluated in the study contained a lower percentage of total chemical fat than loin cuts on a raw basis. When total chemical fat was stratified by USDA quality grade, it was evident that there was a clear separation between upper Choice, lower Choice, and Select cuts.
Data resulting from this study will be used to update the existing nutritional database and will provide a current nutritional profile for beef loin and round products.
