title: The influence of cheese composition and microstructure on the diffusion of macromolecules: A study using Fluorescence Recovery After Photobleaching (FRAP).
abstract: In cheese technology, the diffusion phenomena are crucial during ripening. The technique of Fluorescence Recovery After Photobleaching was applied for the first time on real cheese, in order to investigate the relationships between molecular diffusion and the cheese composition and/or its microstructure. Measured effective diffusion coefficients in soft and hard cheese of a group of dextrans (10-500 kDa) were found to be in the same order of magnitude with values observed when using a comparable non-fat model cheese (∼ 0.1-20 μm(2) s(-1)). Diffusion of the dextrans was mainly dependent on the fraction of "free" aqueous phase present in the cheese, closely which is linked to cheese-making technology and ripening stage. Diffusion coefficients were modeled by a power law relationship as a function of dextran molecular weight, which allowed some study of the cheese microstructure. A tighter protein network will require some deformation of those flexible macromolecules with a higher molecular weight (>250 kDa), in order to diffuse through the pores of such cheese structures.
authors: INRA, UMR1253, Science and Technology of Milk and Eggs, F-35042 Rennes Cedex, France.
authors: A L
authors: AL
authors: Chapeau
authors: INRA, UMR1253, Science and Technology of Milk and Eggs, F-35042 Rennes Cedex, France.
authors: Juliana V C
authors: JV
authors: Silva
authors: INRA, UMR1253, Science and Technology of Milk and Eggs, F-35042 Rennes Cedex, France.
authors: Pierre
authors: P
authors: Schuck
authors: INRA, UMR1253, Science and Technology of Milk and Eggs, F-35042 Rennes Cedex, France.
authors: Anne
authors: A
authors: Thierry
authors: INRA, UMR1253, Science and Technology of Milk and Eggs, F-35042 Rennes Cedex, France; AGROCAMPUS OUEST, UMR1253, Science and Technology of Milk and Eggs, F-35042 Rennes Cedex, France. Electronic address: Juliane.Floury@agrocampus-ouest.fr.
authors: Juliane
authors: J
authors: Floury
mesh_terms: D002611:Cheese / Q000032:analysis*; D003911:Dextrans / Q000737:chemistry; D004058:Diffusion; D036681:Fluorescence Recovery After Photobleaching / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry*; D008962:Models, Theoretical; D008970:Molecular Weight
chemical_list: D003911:Dextrans; D046911:Macromolecular Substances
keywords: Cheese; Fluorescence Recovery After Photobleaching (FRAP); Microstructure; Ripening; Water