title: Green tea extract impairs meat emulsion properties by disturbing protein disulfide cross-linking.
abstract: The dose-dependent effects of green tea extract (100, 500, or 1500ppm) on the textural and oxidative stability of meat emulsions were investigated, and compared to a control meat emulsion without extract. All levels of green tea extract inhibited formation of TBARS as a measure for lipid oxidation. Overall protein thiol oxidation and myosin heavy chain (MHC) cross-linking were inhibited by 100ppm green tea extract without jeopardizing the textural stability, while increasing concentrations of extract resulted in reduced thiol concentration and elevated levels of non-reducible protein modifications. Addition of 1500ppm green tea extract was found to modify MHC as evaluated by SDS-PAGE combining both protein staining and specific thiol staining, indicating that protein modifications generated through reactions of green tea phenolic compounds with protein thiols, disrupted the meat emulsion properties leading to reduced water holding capacity and textural stability. Hence, a low dose of green tea extract preserves both the textural and the oxidative stability of the meat proteins.
authors.affiliation: Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, 1958 Frederiksberg, Denmark. Electronic address: Jongberg@food.ku.dk.
authors.forename: Sisse
authors.initials: S
authors.lastname: Jongberg
authors.affiliation: Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, 1958 Frederiksberg, Denmark. Electronic address: lte@food.ku.dk.
authors.forename: Linda de S
authors.initials: LS
authors.lastname: Terkelsen
authors.affiliation: Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, 1958 Frederiksberg, Denmark. Electronic address: miklos@food.ku.dk.
authors.forename: Rikke
authors.initials: R
authors.lastname: Miklos
authors.affiliation: Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, 1958 Frederiksberg, Denmark. Electronic address: mnl@food.ku.dk.
authors.forename: Marianne N
authors.initials: MN
authors.lastname: Lund
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry*; D028241:Camellia sinensis / Q000737:chemistry*; D004220:Disulfides / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D015227:Lipid Peroxidation; D008460:Meat; D008461:Meat Products / Q000032:analysis*; D010636:Phenols / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D013552:Swine; D017392:Thiobarbituric Acid Reactive Substances; D014867:Water
chemical_list: D000975:Antioxidants; D004220:Disulfides; D004655:Emulsions; D010636:Phenols; D010936:Plant Extracts; D011506:Proteins; D017392:Thiobarbituric Acid Reactive Substances; D014867:Water
keywords: Disulfide bridges; Meat emulsions; Oxidation; Phenolic antioxidants; Protein cross-links; Texture