title: A judgment on postmortem aging in longissimus dorsi based on a peptide substrate library.
abstract: We attempted to develop a method to determine easily and effectively the degree of postmortem aging of pork longissimus dorsi (LD) by measuring the activity of proteases in the LD using fluorogenic peptide substrates. LD was used to measure the change with time in the protease activity detected with these substrates. Determining the variations within the LD muscles, strong positive correlations were found between changes in hardness and fluorescence intensities against Ac-Ala-MCA, Ac-Met-MCA, Ac-Ser-MCA, Ac-Thr-MCA, and Ac-Ala-Phe-MCA (P<0.005), and strong negative correlations were found between changes in total amounts of free amino acids and Ac-Ala-MCA, Ac-Met-MCA, Ac-Ser-MCA, Ac-Thr-MCA, and Ac-Ala-Phe-MCA (P<0.001). Negative correlations were also observed between changes in the amounts of free Ala, Arg, Lys, Leu, Met, Phe, and Tyr and the fluorescence intensities against Ala, Arg, Lys, Leu, Met, Phe, and Tyr-MCA respectively (P<0.001).
authors.affiliation: Research and Development Center, Nippon Meat Packers, Inc., Tsukuba, Ibaraki. eonitsuka@nipponham.co.jp
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Onitsuka
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Okumura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Murakami
authors.forename: Norikazu
authors.initials: N
authors.lastname: Nishino
authors.forename: Fumiki
authors.initials: F
authors.lastname: Morimatsu
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D018482:Muscle, Skeletal / Q000502:physiology; D019151:Peptide Library; D011180:Postmortem Changes; D013552:Swine
chemical_list: D000596:Amino Acids; D019151:Peptide Library