Potential Antioxidant and Angiotensin I-converting Enzyme Inhibitory Activity in Crust of Dry-aged Beef.

Antioxidant activity, angiotensin I-converting enzyme (ACE) inhibitory activity, and protein profile of crust (the dried surface of dry-aged beef) were evaluated compared to unaged, wet-, and dry-aged beef. Antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-di-(3-ethylbenzthiazoline sulfonate) radical scavenging activities, ferric reducing antioxidant power, and ferrous ion chelating activity. The crust samples showed the greatest (P < 0.05) ACE inhibitory and antioxidant activity resulting from the three different mechanisms of action (radical scavenging, non-radical redox potential activity, and metal chelating) among the treatments. Small molecular weight protein bands and small peptides (<3 kDa) indicating potent bioactivity were evident in the myofibrillar protein profile of crust samples. The lowest (P < 0.05) ACE inhibitory activity was observed in unaged beef. The results indicate that crust could be utilized in various areas as a functional ingredient possessed antioxidant and ACE inhibitory activity instead of being discarded. In addition, dry aging can use for generation of functional ingredient from beef as the regime.