Summary and Implications
Desmin degradation provides an indication of the extent of protein degradation that occurs during aging in postmortem muscle. The vastus lateralis had the highest amount of desmin degradation at 24 hours. However, the vastus lateralis had no change in desmin degradation over time. This provides evidence that the majority of degradation in the vastus lateralis occurs within 24 hrs postmortem. Previous data from our lab has shown that after this point, further aging of this muscle is not be highly beneficial because little additional tenderization occurs. While the semimembranosus did have a high amount of desmin degradation at 7 days it also contains a high amount of connective tissue. This connective tissue will make the semimembranosus less tender regardless of the amount of degradation. The gracillus and vastus intermedius had an increase in desmin degradation over time. Aging these cuts longer may provide us with a tender product that could be marketed as an individual cut. While the muscles of the round are treated similarly, each muscle has its own individual rate and extent of desmin degradation. Given that these biochemical differences exist, these muscles need to be evaluated individually to optimize the tenderness in each cut.
Iowa State University
Anderson, Mark J.; Binning, Jennifer; Lonergan, Steven M.; and Huff-Lonergan, Elisabeth J.
"Postmortem Degradation of Desmin in Specific Muscles from the Beef Round,"
Animal Industry Report:
AS 655, ASL R2395.
Available at: http://lib.dr.iastate.edu/ans_air/vol655/iss1/18