Submitted to: Journal of Muscle Foods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 15, 2007
Publication Date: January 7, 2008
Citation: Bowker, B.C., Fahrenholz, T.M., Paroczay, E.W., Eastridge, J.S., Solomon, M.B. 2008. Effect of hydrodynamic pressure processing and aging on the tenderness and myofibrillar proteins of beef strip loins. Journal of Muscle Foods. 19:74-97. Interpretive Summary: Evaluating the effects of hydrodynamic pressure processing (HDP) and aging on fresh beef strip loins, this study found that HDP caused immediate improvements in tenderness that were further enhanced by aging. Control samples required 8 days of aging to attain the level of tenderness achieved by non-aged HDP treated samples. Data suggests that HDP tenderization is caused by protein degradation and physical disruption of the muscle ultrastructure.
Technical Abstract: This study evaluated the effects of hydrodynamic pressure processing (HDP) and aging on the tenderness and myofibrillar proteins of beef strip loins. Loins (n=12) were halved at 48 h postmortem and assigned to HDP or control treatments. Following treatment, each half was divided into three portions for aging (0, 5, or 8 days). Samples were removed for Warner-Bratzler shear force (WBSF) determination and myofibrillar protein isolation. HDP decreased (P<0.0001) WBSF values 23 percent at 0, 5, and 8 days of aging. Myofibrillar fragmentation and myofibrillar protein solubility increased (P<0.01) with HDP and aging. SDS-PAGE and western blotting analysis of myofibrillar proteins showed that HDP and aging decreased intensity of the troponin-T band and enhanced accumulation of the 30 kDa troponin-T degradation product. These data suggest HDP is more effective than aging tenderization and that HDP tenderization is caused by protein degradation and physical disruption of the myofibril apparatus.