Effect of zilpaterol hydrochloride supplementation of beef steers and calf-fed Holstein steers on the color stability of top sirloin butt steaks.

Top sirloin butt steaks were used to determine the effects on color stability of supplementing zilpaterol hydrochloride (ZH) to beef and calf-fed Holstein steers. This study compared the effects of dietary ZH supplementation for 0, 20, 30, or 40 d on feed. One-half of the top sirloin butts were enhanced and packaged in modified-atmosphere packaging (MAP); the remaining one-half were packaged in polyvinylchloride (PVC) film. Beef steaks packaged with PVC from cattle supplemented for 30 d had a tendency (P = 0.07) to produce a redder (a* = 18.31) steak than the control cattle (a* = 17.00) or cattle supplemented for 40 d (a* = 17.05). In beef steaks, ZH had no effect on subjective visual color (P = 0.15 to 0.27) and discoloration (P = 0.10 to 0.59) of steaks packaged with PVC when stratified by day of display, with the exception of visual color on d 5. Beef steaks under MAP from cattle supplemented for 20 d were redder (a* = 19.50, P < 0.05) than those from cattle supplemented for 30 (a* = 18.07) or 40 d (a* = 17.57), but were similar to the control steaks (a* = 18.68). There was no effect (P > 0.05) of retail display day and day of supplementation on objective or subjective color of calf-fed Holstein steaks packaged with PVC. Dietary supplementation for 20 d produced a greater (P < 0.05) b* value on d 1 of display in MAP-packaged steaks from calf-fed Holsteins. If recommending a period of dietary supplementation, 20 to 30 d would be suggested to result in, on average, the brightest, reddest sirloin butt steaks.