title: Effects of oxidative modification on gel properties of isolated porcine myofibrillar protein by peroxyl radicals.
abstract: AAPH-derived (2,2'-azobis (2-amidinopropane) dihydrochloride) peroxyl radicals were selected as representative free radicals of lipid peroxidation to investigate the effects of oxidative modifications on isolated porcine myofibrillar protein structures as well as their rheological and gelling properties. Incubation of myofibrillar protein with increasing concentrations of AAPH resulted in a gradual increase (p<0.05) in carbonyl content and SH→S-S conversion. Results from SDS-PAGE indicated that medium (~1 mM) and relatively high (>3 mM) concentrations of AAPH induced aggregation of myosin and denaturation of myosin, troponin and tropomyosin, respectively. These structural changes resulted in changes on gelation of myofibrillar protein. Low level protein oxidation (AAPH≤0.5 mM) had no remarkable effect (p>0.05) on the viscoelastic pattern of myofibrillar protein gelation. Moderate oxidative modification (AAPH~1mM) enhanced the water-holding capacity (WHC) and texture properties of gels, while further oxidation (AAPH>3mM) significantly reduced the gel quality.
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Feibai
authors.initials: F
authors.lastname: Zhou
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Mouming
authors.initials: M
authors.lastname: Zhao
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhao
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China. Electronic address: fewzhsun@scut.edu.cn.
authors.forename: Weizheng
authors.initials: W
authors.lastname: Sun
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Chun
authors.initials: C
authors.lastname: Cui
mesh_terms: D000818:Animals; D004548:Elasticity; D005609:Free Radicals / Q000378:metabolism*; D005782:Gels; D006801:Humans; D015227:Lipid Peroxidation; D008460:Meat / Q000032:analysis*; D009124:Muscle Proteins / Q000302:isolation & purification / Q000378:metabolism*; D009210:Myofibrils / Q000378:metabolism*; D009218:Myosins / Q000378:metabolism; D010084:Oxidation-Reduction; D010545:Peroxides / Q000378:metabolism*; D050050:Protein Carbonylation; D012212:Rheology; D013552:Swine; D014335:Tropomyosin / Q000378:metabolism; D014336:Troponin / Q000378:metabolism; D014867:Water
chemical_list: D005609:Free Radicals; D005782:Gels; D009124:Muscle Proteins; D010545:Peroxides; D014335:Tropomyosin; D014336:Troponin; D014867:Water; C049375:perhydroxyl radical; D009218:Myosins
keywords: Gelation; Microstructure; Myofibrillar protein; Peroxyl radical; Protein oxidation