Metabolite Profile Differences between Beef Longissimus and Psoas Muscles during Display

The objective of this research was to compare metabolite profiles between beef and muscles during display. Beef short loins were collected 3 d postmortem ( = 10). Steaks were cut from each (LL) and (PM) muscle and displayed under retail conditions for 7 d. Surface color, biochemical properties, and metabolites were analyzed during storage. PM decreased in redness ( < 0.05) by d 3 of display compared with LL. There were differences in metabolite concentrations ( < 0.05) between each muscle type at each time point. Sugars, amino acids, tricarboxylic acid cycle intermediates, and glycolytic substrates were detected in both muscles. Glycolytic metabolites such as pyruvic acid, glucose–6–phosphate, and fructose were greater ( < 0.05) in LL than PM at all display times. On d 0, the intensity of pyruvic acid in LL and PM were 142 and 42, respectively. Citric acid and succinic acid were lower on d 0, but were greater ( < 0.05) in LL compared with PM by d 7 of display. Carnitine was lower ( < 0.05) in LL than PM at all display times. On d 7, carnitine level in LL was 4.1 while in PM was 13,500. The results suggest that in addition to muscle-specific differences in mitochondrial and enzyme activities, inherent metabolite differences also may contribute to muscle color stability