title: Mitochondrial oxygen consumption in permeabilized fibers and its link to colour changes in bovine M. semimembranosus muscle.
abstract: Animal and muscle characteristics were recorded for 41 cattle. The oxygen consumption rate (OCR) of M. semimembranosus was measured between 3.0-6.4h post mortem (PM3-6) and after 3 weeks in a vacuum pack at 4°C. Colour change measurements were performed following the 3 weeks using reflectance spectra (400-1,100 nm) and the colour coordinates L, a and b, with the samples being packaged in oxygen permeable film and stored at 4°C for 167 h. Significant individual animal differences in OCR at PM3-6 were found for mitochondrial complexes I and II. OCR of complex I declined with increased temperature and time PM, while residual oxygen-consuming side-reactions (ROX) did not. OCR of stored muscles was dominated by complex II respiration. A three-way regression between samples, colour variables collected upon air exposure and OCR of 3 weeks old fibres revealed a positive relationship between OCR and complex II activity and also between OCR and OCR(ROX). The presence of complex I and β-oxidation activities increased metmyoglobin formation.
authors.affiliation: Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Ås, Norway. vinh.phung@umb.no
authors.forename: V T
authors.initials: VT
authors.lastname: Phung
authors.forename: M
authors.initials: M
authors.lastname: Khatri
authors.forename: K H
authors.initials: KH
authors.lastname: Liland
authors.forename: E
authors.initials: E
authors.lastname: Slinde
authors.forename: O
authors.initials: O
authors.lastname: Sørheim
authors.forename: T
authors.initials: T
authors.lastname: Almøy
authors.forename: K
authors.initials: K
authors.lastname: Saarem
authors.forename: B
authors.initials: B
authors.lastname: Egelandsdal
mesh_terms: D000388:Air; D000818:Animals; D002417:Cattle; D019069:Cell Respiration; D003116:Color; D042967:Electron Transport Complex I / Q000378:metabolism; D042963:Electron Transport Complex II / Q000378:metabolism; D044927:Electron-Transferring Flavoproteins / Q000378:metabolism*; D018857:Food Packaging; D061353:Food Storage; D008460:Meat / Q000032:analysis*; D008786:Metmyoglobin / Q000096:biosynthesis; D008928:Mitochondria / Q000378:metabolism*; D018485:Muscle Fibers, Skeletal / Q000378:metabolism; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D010539:Permeability; D011180:Postmortem Changes; D012034:Refrigeration; D013696:Temperature; D014618:Vacuum
chemical_list: D044927:Electron-Transferring Flavoproteins; D008786:Metmyoglobin; D042963:Electron Transport Complex II; D042967:Electron Transport Complex I; D010100:Oxygen