Research Article

Possible Role of Myoglobin in Regulating Calpain-1 Activity in Postmortem Beef Muscle

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Abstract

ObjectivesPrevious research revealed a relationship between meat color and beef tenderness and indicated that myoglobin can inhibit calpain-1 in solution. The objective of this study was to determine the extent to which myoglobin and beef color are associated with calpain activity and beef tenderness.Materials and MethodsBeef Longissimus dorsi samples from the left side of Holstein beef carcasses (n = 21) were collected immediately post exsanguination on the processing floor for 0 h analyses. Muscle temperature and pH was measured at 0, 24, and 48 h postmortem. After USDA quality and yield grade determination, steaks (n = 6) were removed from the right side of each carcass (n = 21) at 48 h for analyses at 48 and 336 h postmortem. Color (L*, a*, and b* values), surface myoglobin redox forms, metmyoglobin reducing activity (MRA), total myoglobin concentrations, slice shear force (SSF), Warner-Bratzler shear force (WBSF) were measured. Calpain-1 concentrations and autolysis were determined via Western blot at 0, 48, and 336 h.ResultsDecline in muscle pH was 6.4, 5.8, and 5.6 at 0, 24, and 48 h, respectively. Shear force values at 48 h were 73.19 N for WBSF and 384.21 N for SSF and at 336 h were 48.75 N for WBSF and 260.47 N for SSF. Myoglobin reducing activity at 336 h was positively correlated to WBSF at 48 h and negatively correlated to calpain-1 concentration at 0 h (P < 0.05; Table 9). Color measurements of L* and b* at 48 h were moderately correlated with WBSF at 336 h (P < 0.05; Table 9). The b* measurement at 336 h showed a moderate relationship to calpain-1 concentration at 0 h (P < 0.05; Table 9).ConclusionModerate correlations between color and tenderness measurements taken at 48 h with those taken at 336 h were discovered indicating that myoglobin may impact calpain-1 in vivo.Table 9Correlations (P-values) between selected color and tenderness measurements (n = 21)

Keywords: calpain activity, myoglobin, meat color, tenderness

How to Cite:

Cooper, J. V., Suman, S., Callahan, Z. D., Kerns, K. C., Zigo, M., Sutovsky, P., Lonergan, S. M. & Lorenzen, C., (2019) “Possible Role of Myoglobin in Regulating Calpain-1 Activity in Postmortem Beef Muscle”, Meat and Muscle Biology 3(2). doi: https://doi.org/10.22175/mmb.10733