Title: Alterations in the sarcoplasmic protein fraction of beef muscle with postmortem aging and hydrodynamic pressure processing Authors
Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 26, 2012
Publication Date: June 1, 2012
Citation: Bowker, B.C., Fahrenholz, T.M., Sarnoski, P.J., Solomon, M.B. 2012. Alterations in the sarcoplasmic protein fraction of beef muscle with postmortem aging and hydrodynamic pressure processing. Journal of Food Science. 77(6):C594-C602. Interpretive Summary: The sarcoplasmic protein component of muscle tissue contains predominantly water-soluble proteins and metabolic enzymes. While sarcoplasmic proteins do not play a structural role in determining meat tenderness, this study utilized analytical techniques to demonstrate that sarcoplasmic protein profiles are altered with changes in beef tenderness caused by aging and hydrodynamic pressure processing. These data suggest that changes in the sarcoplasmic protein fraction of beef may potentially be useful as indicators of meat tenderness.
Technical Abstract: Capillary electrophoresis (CE) and reversed-phase high performance liquid chromatography (RP-HPLC) analysis were utilized to detect differences in the sarcoplasmic protein profiles of beef strip loins subjected to aging and hydrodynamic pressure processing (HDP) treatments. At 48 h postmortem, strip loins (n=12) were halved and subjected to control or HDP treatments. Following treatment, each half was divided into three portions which were aged for 0, 5, and 8 days. After each aging period, steaks were removed for Warner-Bratzler shear force (WBSF) analysis and for the isolation of sarcoplasmic protein fractions which were analyzed by CE and RP-HPLC. Aging by HDP interactions were not detected within the sarcoplasmic protein fractions using either separation technique. With CE analysis, no significant HDP effects were observed; however, the relative peak area of eight protein peaks ranging in size from 17 to >200 kDa were influenced by postmortem aging. RP-HPLC separation of sarcoplasmic fractions demonstrated that HDP influenced the relative size of two protein peaks while postmortem aging effects were observed in six peaks. Alterations in the sarcoplasmic protein fraction detected by both CE and RP-HPLC were significantly correlated to WBSF measurements. Overall, data demonstrate that aging and HDP have additive effects on sarcoplasmic proteins and suggest that changes in sarcoplasmic protein profiles may be useful indicators of tenderness.