Submitted to: Meat Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/25/2010
Publication Date: 1/20/2011
Citation: King, D.A., Shackelford, S.D., Rodriguez, A.B., Wheeler, T.L. 2011. Effect of time of measurement on the relationship between metmyoglobin reducing activity and oxygen consumption to instrumental measures of beef longissimus color stability. Meat Science. 87(1):26-32. Interpretive Summary: Supermarkets lose millions of dollars due to discounted or discarded meat resulting from discoloration. We recently demonstrated a significant genetic contribution to animal-to-animal variation in lean color stability. The objective of the present study was to determine the biochemical mechanisms associated with the variation in lean color stability. Results indicate both initial and sustained levels of various factors affecting color stability contribute to animal variation in lean color stability. These data will lead to strategies to improve lean color stability and a reduction in the losses incurred by retail supermarkets due to meat discoloration.
Technical Abstract: The contribution 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 thoracis 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.