title: Protein oxidation and protein nitration influenced by sodium nitrite in two different meat model systems.
abstract: The effect of NaNO2 on protein oxidation was studied in isolated myofibrillar protein isolates (100 and 1000 mg NaNO2/kg) and in porcine patties (18 and 180 mg NaNO2/kg). In addition, the potential use of 3-nitrotyrosine as a specific marker for reactive nitrogen species mediated nitration was investigated. Overall, no distinct pro- or antioxidant effect of NaNO2 against carbonyl formation was observed in the isolates or in the patties. However, in the isolates, higher protein carbonyl concentrations were found in the NaNO2-treated samples compared to the treatment without added nitrite immediately after the addition of oxidants and NaNO2. Addition of 180 mg NaNO2/kg to patties resulted in significantly lower thiol concentrations at 4 and 7 days of illuminated chilled display compared to the treatments with 0 and 18 mg/kg NaNO2, whereas no effect was observed in the isolates. No effect of NaNO2 was found on the protein solubility of either meat model. 3-Nitrotyrosine was present in all samples, but no clear effect of NaNO2 addition or oxidation time was observed.
authors.affiliation: Laboratory for Animal Nutrition and Animal Product Quality, Department of Animal Production, Faculty of Bioscience Engineering, Ghent University , Proefhoevestraat 10, 9090 Melle, Belgium.
authors.forename: Els
authors.initials: E
authors.lastname: Vossen
authors.forename: Stefaan
authors.initials: S
authors.lastname: De Smet
mesh_terms: D000818:Animals; D008461:Meat Products / Q000032:analysis*; D008954:Models, Biological; D009124:Muscle Proteins / Q000737:chemistry*; D009210:Myofibrils / Q000737:chemistry; D010084:Oxidation-Reduction; D012977:Sodium Nitrite / Q000737:chemistry*; D013552:Swine
chemical_list: D009124:Muscle Proteins; D012977:Sodium Nitrite
keywords: 3-nitrotyrosine; meat; nitrite; protein oxidation