title: Effects of pH and NaCl levels in a beef marinade on physicochemical states of lipids and proteins and on tissue microstructure.
abstract: Meat slices were incubated for 24h at 10°C in marinade solutions so that their pH reached 6.5, 5.4, or 4.3, and their NaCl contents 0.9% or 2%. The histological modifications were assessed by image analysis using two parameters: mean fibre cross section area (FCSA, μm(2)) and the ratio of the extra-cellular space (ECS, % area). The changes in lipids and proteins were evaluated through oxidation, protein surface hydrophobicity, and protein aggregation by granulometry (size and shape of particles). ANOVA showed that FCSA decreased linearly while ECS increased when pH decreased from 6.5 to 4.3 at either low or high NaCl salt content. Decreasing pH significantly increased TBARS and carbonyl groups, while increasing NaCl level had a significant protective effect on lipids. No marinating effect was observed on free thiols. Protein surface hydrophobicity and aggregation increased significantly with decreasing pH, but were unaffected by NaCl. The effect of these physicochemical changes on the nutritional value of meat is discussed.
authors.affiliation: INRA UR370 Qualité des Produits Animaux, 63122 St Genès Champanelle, France.
authors.forename: Diaa
authors.initials: D
authors.lastname: Sharedeh
authors.affiliation: INRA UR370 Qualité des Produits Animaux, 63122 St Genès Champanelle, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Gatellier
authors.affiliation: INRA UR370 Qualité des Produits Animaux, 63122 St Genès Champanelle, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Astruc
authors.affiliation: INRA UR370 Qualité des Produits Animaux, 63122 St Genès Champanelle, France. Electronic address: jean-dominique.daudin@clermont.inra.fr.
authors.forename: Jean-Dominique
authors.initials: JD
authors.lastname: Daudin
mesh_terms: D000818:Animals; D002417:Cattle; D004041:Dietary Fats / Q000032:analysis*; D004044:Dietary Proteins / Q000032:analysis*; D005511:Food Handling / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D015227:Lipid Peroxidation; D008055:Lipids / Q000032:analysis* / Q000737:chemistry; D009124:Muscle Proteins / Q000032:analysis*; D018482:Muscle, Skeletal; D009753:Nutritive Value; D010084:Oxidation-Reduction; D050050:Protein Carbonylation; D000069466:Red Meat / Q000032:analysis*; D012965:Sodium Chloride / Q000737:chemistry*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D004041:Dietary Fats; D004044:Dietary Proteins; D008055:Lipids; D009124:Muscle Proteins; D017392:Thiobarbituric Acid Reactive Substances; D012965:Sodium Chloride
keywords: Beef; Brining; Lipid oxidation; Marinating; Microstructure; Protein changes