Bioactive peptides in beef: Endogenous generation through postmortem aging

The present research was performed to investigate endogenous release of bioactive peptides in beef during postmortem aging times (1, 10 and 20 days). Gradually decreased Warner-Bratzler shear force (WBSF) values of longissimus thoracis (LT) and semitendinosus (ST) muscles were observed and the degradation of structural proteins and collagen led to release of low-molecular weight (< 3 kDa) peptides. These peptides exhibited 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, ACE- and renin-inhibitory activities. The peptide sequences were identified by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). In silico analysis (PeptideRanker and BIOPEP) of their bioactivity potentials demonstrated peptides with the predicted bioactivity scores (> 0.8) as well as collagen peptides with bioactivity scores (0.6-0.8). The present findings provide insights on development of healthy beef through postmortem aging at 4 °C.