title: A phenomenological and thermodynamic study of the water permeation process in corn starch/MMT films.
abstract: Water transport in edible films of starch based products is a complex phenomenon due to the strong interaction of sorbed water molecules with the polymeric structure of starch. Moisture sorption isotherms of starch and starch/MMT films were obtained. The results indicated that nanoclay incorporation produces a decrease of water uptake at all temperatures analysed. Thermodynamic parameters showed that sorption process is less favourable when MMT is incorporated into the starch matrix. Effect of driving force and water activity (aw) values at each side of the film on permeability and diffusivity coefficients were analysed. The effect of the tortuous pathway generated by MMT incorporation was significant only in the middle and lower range of aw. At high aw range the plasticizing effect of water dominated and MMT incorporation had little effect on the water barrier properties of these films.
authors.affiliation: Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT), CIUNSa, Universidad Nacional de Salta, Av. Bolivia 5150, A4408TVY, Salta, Argentina.
authors.forename: Aníbal M
authors.initials: AM
authors.lastname: Slavutsky
authors.affiliation: Instituto de Investigaciones para la Industria Química (CONICET), CIUNSa, Facultad de Ingeniería, Universidad Nacional de Salta, Av. Bolivia 5150, A4408TVY, Salta, Argentina.
authors.forename: María A
authors.initials: MA
authors.lastname: Bertuzzi
mesh_terms: D001546:Bentonite / Q000737:chemistry* / Q000378:metabolism; D010539:Permeability; D013213:Starch / Q000737:chemistry* / Q000378:metabolism; D013816:Thermodynamics; D014867:Water / Q000737:chemistry* / Q000378:metabolism; D014961:X-Ray Diffraction / Q000379:methods; D003313:Zea mays
chemical_list: D014867:Water; D001546:Bentonite; D013213:Starch