title: Effect of time of measurement on the relationship between metmyoglobin reducing activity and oxygen consumption to instrumental measures of beef longissimus color stability.
abstract: Contributions of initial and retained levels of oxygen consumption and reducing capacity to animal variation in color stability were evaluated. Instrumental color values were determined on longissimus steaks (n=257) during 6 d of display. Oxygen consumption (OC), nitric oxide metmyoglobin reduction (NORA), initial metmyoglobin formation (IMF), and post-reduction metmyoglobin (PRM) were measured on d 0 and 6. During display, color variables, OC and reducing ability decreased (P<0.05). Color stable steaks had greater (P<0.05) reducing ability on d 0 and 6 and lower (P<0.05) OC on d 0 than unstable steaks. Color change was correlated to OC, NORA, and PRM on d 0 (r=0.19, -0.44 and 0.45, respectively) and to NORA and PRM on d 6 (r=-0.50 and 0.52, respectively). These data suggest that initial capacity for OC and reducing ability, combined with retained reducing ability contribute to animal variation in color stability.
authors.affiliation: USDA-ARS, US Meat Animal Research Center, P.O. Box 166/State Spur 18D, Clay Center, NE, 68933, United States. andy.king@ars.usda.gov
authors.forename: D A
authors.initials: DA
authors.lastname: King
authors.forename: S D
authors.initials: SD
authors.lastname: Shackelford
authors.forename: A B
authors.initials: AB
authors.lastname: Rodriguez
authors.forename: T L
authors.initials: TL
authors.lastname: Wheeler
mesh_terms: D000818:Animals; D002417:Cattle; D003116:Color; D005519:Food Preservation / Q000379:methods; D008460:Meat / Q000032:analysis*; D008786:Metmyoglobin / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D019163:Reducing Agents / Q000378:metabolism*; D013997:Time Factors
chemical_list: D019163:Reducing Agents; D008786:Metmyoglobin; D009569:Nitric Oxide