title: Effects of zilpaterol hydrochloride feeding duration on crossbred beef semimembranosus steak color in aerobic or modified atmosphere packaging.
abstract: The objective of this research was to determine the effects of feeding zilpaterol hydrochloride (ZH) for 0, 20, 30, or 40 d before slaughter (ZH0, ZH20, ZH30, or ZH40, respectively) on semimembranosus (SM) color development and stability. A 7.62-cm-thick portion was removed from 60 beef steer SM subprimals and stored (2 degrees C) for 21 d; then two 2.54-cm-thick steaks were cut, overwrapped with polyvinyl chloride (PVC) film, and assigned to 0 or 3 d of display. Remaining portions of the subprimals were stored in a vacuum for 10 d and then enhanced 10% to a meat concentration of 0.3% sodium chloride, 0.35% phosphate, and 0.05% rosemary extract. Steaks were packaged in a high-oxygen (HO-MAP) or carbon monoxide (CO-MAP) modified atmosphere and assigned to 0, 3, or 5 d (HO-MAP) or 0 or 9 d (CO-MAP) of display. The deep (DSM) and superficial (SSM) portions of steaks were evaluated for initial color, display color, discoloration, pH, L*, a*, b*, hue angle, and saturation indices. For steaks in PVC, no differences (P > 0.05) occurred in initial or discoloration color scores because of ZH feeding duration. The enhanced SSM steaks from ZH20 in PVC were brighter red (P < 0.05) than SSM steaks from ZH40 in PVC. The DSM in PVC had less (P < 0.05) pH and paler (P < 0.05) color than the SSM. Display color scores for the DSM of PVC steaks were brighter red (P < 0.05) than the SSM initially (d 0 and 1), but the DSM discolored faster (P < 0.05) than the SSM on d 1 to 3. The SM steaks from steers fed ZH20 or ZH30 were slightly brighter and less discolored during display in PVC than the ZH40 diet. For enhanced steaks in HO-MAP, the DSM of ZH20 and ZH30 diets displayed 4 d and the DSM of ZH20 displayed 5 d was a brighter (P < 0.05) red than the DSM from ZH40. At display d 1 and 5, the SSM of ZH20 steaks in HO-MAP was a brighter (P < 0.05) red than SSM steaks from ZH40. The SSM of ZH40 HO-MAP steaks was darker (P < 0.05) red on d 3 than the SSM from other diets. For enhanced steaks in CO-MAP, ZH30 steaks were brighter (P < 0.05) red than ZH0 or ZH40 steaks on d 0 and 9 of display. Steaks in CO-MAP from all feeding durations were less than 20% discolored through d 9. The DSM was lighter (P < 0.05) than the SSM on d 0 for steaks packaged in HO-MAP and CO-MAP. Feeding cattle ZH for 20 or 30 d will yield steaks with color characteristics equal to or better than steaks from control cattle, whereas feeding ZH for 40 d will likely produce less desirable meat color traits.
authors.affiliation: Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506-0201, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Gunderson
authors.forename: M C
authors.initials: MC
authors.lastname: Hunt
authors.forename: T A
authors.initials: TA
authors.lastname: Houser
authors.forename: E A E
authors.initials: EA
authors.lastname: Boyle
authors.forename: M E
authors.initials: ME
authors.lastname: Dikeman
authors.forename: D E
authors.initials: DE
authors.lastname: Johnson
authors.forename: D L
authors.initials: DL
authors.lastname: VanOverbeke
authors.forename: G G
authors.initials: GG
authors.lastname: Hilton
authors.forename: C
authors.initials: C
authors.lastname: Brooks
authors.forename: J
authors.initials: J
authors.lastname: Killefer
authors.forename: D M
authors.initials: DM
authors.lastname: Allen
authors.forename: M N
authors.initials: MN
authors.lastname: Streeter
authors.forename: W T
authors.initials: WT
authors.lastname: Nichols
authors.forename: J P
authors.initials: JP
authors.lastname: Hutcheson
authors.forename: D A
authors.initials: DA
authors.lastname: Yates
mesh_terms: D000332:Aerobiosis; D000821:Animal Feed; D000818:Animals; D002417:Cattle / Q000502:physiology; D003116:Color; D005503:Food Additives / Q000008:administration & dosage / Q000494:pharmacology*; D018857:Food Packaging / Q000379:methods*; D008297:Male; D008460:Meat / Q000592:standards*; D008462:Meat-Packing Industry; D013997:Time Factors; D014297:Trimethylsilyl Compounds / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D005503:Food Additives; D014297:Trimethylsilyl Compounds; C475840:Zilpaterol