Generation of bioactive peptides from duck meat during post-mortem aging

The objective of this study was to investigate the endogenous release of bioactive peptides in duck meat during 7 days of post-mortem aging. The degradation of muscle proteins led to release of small peptides (<5 kDa). The peptides formed in the samples after 3 days post-mortem exhibited highest DPPH radical scavenging, oxygen radical scavenging (ORAC) and ferric reducing antioxidant power (FRAP). By using size-exclusion chromatography, the initial extract was purified into three fractions (A-C) in which fraction C exhibited the highest antioxidant activity. In total 18 peptides were sequenced and identified in the fractions by nano LC-MS/MS. Among these peptides, the peptides of fraction C possessed the lowest molecular weight and consisted of the highest amount of hydrophobic amino acid, which might be responsible for the antioxidant property of aged duck meat. The present findings provide an insight into the release of bioactive peptides in duck meat during post-mortem aging.