Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 24, 2014
Publication Date: July 1, 2014
Citation: Bowker, B.C., Eastridge, J.S., Solomon, M.B. 2014. Measurement of muscle exudate protein composition as an indicator of beef tenderness. Journal of Food Science. 79(7):C1292-C1297. Interpretive Summary: The identification of protein markers is an important step in the development of rapid, non-invasive methodologies for predicting beef tenderness. Moisture that accumulates on the surface and in the packaging of fresh beef is known as exudate and is abundant in muscle proteins. This study demonstrated that the protein profile of beef exudates is influenced by postmortem aging and that the abundance of several individual proteins within the exudate is closely related to beef tenderness. These data suggest that muscle exudate may be a good source of protein markers for beef tenderness prediction.
Technical Abstract: The objective was to determine the relationship between the protein composition of muscle exudate and beef tenderness. Strip loins (n = 24) were divided into 3 sections, vacuum packaged, and aged at 4°C. After 0, 7, and 14 days, shear force was measured and muscle exudate was analyzed for protein content (biuret assay) and composition (SDS-PAGE). Shear force decreased (P < 0.0001) with aging from 0 to 14 days. Aging did not influence the overall protein concentration of muscle exudate. Within SDS-PAGE profiles of exudates, the relative abundance of 4 proteins decreased (P<0.01) and 10 proteins increased (P<0.05) with aging. The relative abundance of the 167, 97, and 47 kDa proteins in exudate at day 0 were significantly correlated (|r| = 0.57 to 0.77) to shear force at day 14. These data suggest that exudate protein composition may be useful in the development of non-invasive methodologies for predicting beef tenderness.