Publicação
Chitosan coating and films: evaluation of surface, permeation, mechanical and thermal propertiess
| Resumo: | The potentialities of chitosan (from lobster of the cuban coasts) coating to extend the shelf life of vegetables were evaluated. To do so, the surface properties of tomato and carrot were characterized and the wettability properties of chitosan coatings were studied. In such coatings, chitosan concentration and effects of type and concentration of plasticizer or surfactant on wettability of chitosan coatings were evaluated, as well as the respective barrier and mechanical properties. Additionally, a blend of chitosan and clay microparticles was performed and the films obtained were characterized in terms of barrier, mechanical and thermal properties. The values of the polar and dispersive components of the superficial tension for the tomato and the carrot were determined, being the superficial tensions of the tomato and carrot 28.55 and 26.40 mN/m, respectively. The results of wettability determinations allowed the construction of one factorial model. The best values of wettability correspond to the following coating composition: 1.5 % (w/v) of chitosan and 0.1 % (w/w) of Tween 80. Acorrelation has been found between the gas permeability coefficients and chitosan concentration (while keeping Tween concentrations constant). The water vapour barrier property of the chitosan films was significantly improved by incorporation of clay, the tensile strength increased significantly with increasing chitosan and clay concentrations, while the values of elongation decreased slightly for high values of chitosan concentration. The obtained models are meant to predict the properties of chitosan/clay films to be prepared. |
|---|---|
| Autores principais: | Casariego, A. |
| Outros Autores: | Souza, B. W. S.; Cruz, L.; Díaz, R.; Teixeira, J. A.; Vicente, A. A. |
| Assunto: | Chitosan Edible coating Surface properties Clay Nanocomposite Gases permeability Mechanical properties Thermal properties Modeling |
| Ano: | 2008 |
| País: | Portugal |
| Tipo de documento: | capítulo de livro |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade do Minho |
| Idioma: | inglês |
| Origem: | RepositóriUM - Universidade do Minho |
| Resumo: | The potentialities of chitosan (from lobster of the cuban coasts) coating to extend the shelf life of vegetables were evaluated. To do so, the surface properties of tomato and carrot were characterized and the wettability properties of chitosan coatings were studied. In such coatings, chitosan concentration and effects of type and concentration of plasticizer or surfactant on wettability of chitosan coatings were evaluated, as well as the respective barrier and mechanical properties. Additionally, a blend of chitosan and clay microparticles was performed and the films obtained were characterized in terms of barrier, mechanical and thermal properties. The values of the polar and dispersive components of the superficial tension for the tomato and the carrot were determined, being the superficial tensions of the tomato and carrot 28.55 and 26.40 mN/m, respectively. The results of wettability determinations allowed the construction of one factorial model. The best values of wettability correspond to the following coating composition: 1.5 % (w/v) of chitosan and 0.1 % (w/w) of Tween 80. Acorrelation has been found between the gas permeability coefficients and chitosan concentration (while keeping Tween concentrations constant). The water vapour barrier property of the chitosan films was significantly improved by incorporation of clay, the tensile strength increased significantly with increasing chitosan and clay concentrations, while the values of elongation decreased slightly for high values of chitosan concentration. The obtained models are meant to predict the properties of chitosan/clay films to be prepared. |
|---|