Filmes inteligentes para o monitoramento de alimentos baseados em amido de lobeira (Solanum lycocarpum)

• Ano de defesa: 2021
• Autor(a) principal: Corrêa, Karytha Merie Silva
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Mato Grosso; Brasil; Instituto de Ciências Exatas e da Terra (ICET) – Araguaia; UFMT CUA - Araguaia; Programa de Pós-Graduação em Ciência de Materiais
• Palavras-chave em Português: Filmes colorimétricos; Indicador microbiológico; Indicador de pH; CNPQ::CIENCIAS EXATAS E DA TERRA; Colorimetric films; Microbiological indicator; pH indicator
• Link de acesso: http://ri.ufmt.br/handle/1/4889

The use of smart films, as colorimetric indicator devices, in food packaging, provides information on the change in pH, time, temperature and microbiological change of the product. These devices make it possible for the consumer to analyze the food with the naked eye, ensuring its safety and quality. Colorimetric indicator films were produced with a polymeric matrix composed of starch from Lobeira (AL) and the plasticizer poly (vinyl acetate) (PVA). Lobeira starch was extracted from Lobeira fruit (Solanum lycocarpum) harvested in the city limits of Pontal do Araguaia - state of Mato Grosso. This starch has a high amylose content, which enables the production of more rigid and resistant films, in addition to being renewable, inexpensive and biodegradable. AL was characterized by scanning electron microscopy (SEM), infrared absorption spectroscopy (FTIR) and thermal analysis. From the polymeric matrix, indicator films containing different concentrations of methylene blue (MB) were obtained by the casting method, with the films MB1, MB2, MB3 and MB4, and the films VN1, VN2 and VN3 containing different concentrations of vanillin (VN). These indicator films were characterized by means of the FTIR spectrum, thermal analysis and analysis by absorption spectroscopy in the visible ultraviolet (UV-vis) region. The FTIR spectra of the films indicated good chemical and physical interaction of the assets with the polymeric matrix. The UV-vis absorption spectra of the films containing MB, show the formation of monomers, dimers and aggregates under the increased concentration of dye in the films. The thermograms of the film containing MB indicate that the interaction of the starch film with the pure MB reduces its degradation temperature and due to the starch and PVA molecules contained in the material, the maximum rate of mass loss is more pronounced in relation to the polymeric matrix. The thermal analysis of the film containing VN suggests that although vanillin is a volatile material, its interaction with the film attenuates the peak corresponding to the maximum rate of mass loss. In this study, a microbiological analysis of chicken meat was carried out at a temperature of 12 and 25 ° C. This test indicated that the VN2 and VN3 films with a concentration of 0.05% and 0.1% presented adequate data for microbiological monitoring of the food. The MB2 film with a concentration of 5% MB, proved to be in agreement with the pH changes, showing to be a good indicator of colorimetric pH.