FRSFCO - Artículos de investigación
Permanent URI for this collectionhttp://48.217.138.120/handle/20.500.12272/1609
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Item Thermal treatment inducing the building-up of tailor-made chitosan films containing gallic acid(Wiley online library, 2025-01-08) Raspo, Matías A.; Gomez, César Gerardo; Andreatta, Alfonsina E.The building-up of chitosan (CS) / gallic acid (GA) films was performed by casting method, thermally pre-processing the reaction mixture at several temperatures and process times. This study was focused on the thermal treatment impact over the antioxidant activity, mechanical deformation at break, water vapor diffusion and surface CS film features. It is found that the thermal energy promotes the diffusion of species through CS chains as well as the GA interaction with the polysaccharide, producing films with different structural organizations. Since the crosslinking degree depends on the energy received by the system, heterogeneous materials with a low chain crosslinking and a high free GA content are generated at 40 °C, while homogeneous films with covalently crosslinking are mostly generated from 50 °C. The free GA availability within segregated CS film regions favors the antioxidant activity, but also the polyphenol interaction with the polysaccharide decreases the crystallinity and elastic modulus, increasing the tensile strength and elongation at break. Since a threshold 516 kJ energy received regulates the transition from heterogeneous to homogeneous films can be thermally tuned. This discovery represents a controlling synthetic factor critical to the design of materials with unique characteristics such as those required for food packaging.Item Antioxidant and antimicrobial activity of bioactive chitosan films.(2022-01-01) Raspo, Matías A.; Vignola, María Belén; Gomez, César Gerardo; Andreatta, Alfonsina E.Interest in the development of films for food preservation is increasing due to the improvement achieved in the food preservation time with the advent of new packaging technologies. Chitosan is a widely used biopolymer produced from the deacetylation of chitin, which has a good capacity to form suitable films as food packages. On the other hand, bioactive compounds such as gallic acid and salicylic acid act as inhibitors of the oxidant activity of free radicals and delay the decomposition of food. In this sense, the preparation of chitosan films modified with the mixture incorporation of salicylic acid/sorbitol or gallic acid/Tween 80 was proposed, using sorbitol or Tween 80 as plasticizers. Both films (chitosan/gallic acid/Tween 80 and chitosan/salicylic acid/sorbitol) showed a good antioxidant capacity in while the chitosan/gallic acid/Tween 80 film evidenced its antimicrobial activity against Escherichia coli ATCC 25922 causing a diminution of unit forming colonyItem Antioxidant and antimicrobial activity of bioactive chitosan films(2022-01-01) Raspo, Matías A.; Vignola, María Belén; Gomez, César Gerardo; Andreatta, Alfonsina E.In this work the preparation of chitosan films containing different bioactive compounds (gallic acid or salicylic acid) and plasticizers (sorbitol or Tween 80) was assessed. In addition, the component composition influence on the performance of chitosan-based films over antimicrobial and antioxidant activity were researched using the Response Surface Methodology from a Doehlert two-factor model. Both films (A: chitosan/gallic acid/Tween 80 and B: chitosan/salicylic acid/sorbitol) showed a good antioxidant capacity where a higher bioactive compound content and a low plasticizer concentration led to the best performance. Furthermore, the chitosan/gallic acid/Tween 80 film evidenced antimicrobial activity against Escherichia coli ATCC 25922. Chitosan-based films developed from formulation A and B showed a promising performance as bacteriostatic agent, which is sufficient evidence to assess these films as successful materials for food packaging.Item Desarrollo de películas bioactivas de quitosano a partir de la atomización de formulaciones líquidas(AJEA- Actas de Jornadas y Eventos Académicos de UTN, 2022-12) Raspo, Matías A.; Bertea, Melina del Valle; Sicardi, Camila María; Gomez, César Gerardo; Andreatta, Alfonsina E.El presente trabajo establece el estudio de las condiciones de atomización de una formulación de quitosano-ácido gálico-sorbitol sobre superficies de papel, teniendo en cuenta la distancia de atomizado, el diámetro del pico de atomizador y la concentración de la formulación. Los resultados observados revelaron que la distribución de partículas atomizadas de la formulación se hace más uniforme a medida que la distancia aumenta. En este sentido, las diluciones en el rango de 7:3 a 4:6 evidencian el mejor desempeño de atomización en términos del grado de homogenización del recubrimiento. La capacidad antioxidante de las superficies atomizadas decrece con la concentración de la formulación, mostrando un valor aceptable de inhibición de DPPH cercano al 80%, hasta la dilución 4:6.