Factors affecting carcass characteristics and palatability of young bulls

Typescript (photocopy).The effects of castration, breed group and growth stimulants on certain carcass characteristics and palatability traits of young bulls were tested. In addition, postmortem aging effects on steer and bull beef were studied. A total of 887 animals were utilized in various portions of this study. Loin samples from one side of each animal were evaluated by a trained sensory panel and by use of the Warner-Bratzler shear machine. In general, steer carcasses were more desirable than bull carcasses for the factors used to determine USDA quality grade. In contrast, bulls produced carcasses that would yield a higher estimated percentage of their weight in boneless, closely trimmed major retail cuts. Loin steaks from steers were more desirable in tenderness, overall palatability and shear force values than were loin steaks from bulls. No differences were found for juiciness, connective tissue amount, incidence of off-flavor or cooking loss between loin steaks from steers and bulls. English and English-cross bull carcasses tended to have more desirable quality grade factors and higher numerical yield grades, whereas Exotic-cross bulls were leaner with lower numerical yield grades. In general, all breed groups of bulls produced carcasses that had very desirable average yield grades. Few statistically significant differences were observed in sensory panel ratings or shear force values for the breed groups utilized in these studies. Sex class (based on masculinity traits) did relate to tenderness differences among loin steaks from bull carcasses in this study. Additional postmortem aging of loin steaks from steer and bull carcasses increased sensory panel tenderness and overall palatability evaluations and reduced shear force values. Attempts to relate carcass characteristics to tenderness differences were of very limited success. Growth stimulants appeared to have no effect on carcass quality factors (although slightly increased carcass fatness may be expected with some implants). In addition, implantation with growth stimulants had little effect on the palatability of loin steaks from carcasses of any of the breed groups tested