46 research outputs found
Thermal and mechanical properties of chitosan nanocomposites with cellulose modified in ionic liquids
In this paper, ionic liquid treatment was applied to produce nanometric cellulose particles of two polymorphic forms. A complex characterization of nanofillers including wide-angle X-ray scattering, Fourier transform infrared spectroscopy, and particle size determination was performed. The evaluated ionic liquid treatment was effective in terms of nanocrystalline cellulose production, leaving chemical and supermolecular structure of the materials intact. However, nanocrystalline cellulose II was found to be more prone to ionic liquid hydrolysis leading to formation larger amount of small particles. Each nanocrystalline cellulose was subsequently mixed with a solution of chitosan, so that composite films containing 1, 3, and 5% mass/mass of nanometric filler were obtained. Reference samples of chitosan and chitosan with micrometric celluloses were also solvent casted. Thermal, mechanical, and morphological properties of films were tested and correlated with properties of filler used. The results of both, tensile tests and thermogravimetric analysis showed a significant discrepancy between composites filled with nanocrystalline cellulose I and nanocrystalline cellulose II
Orientação nutricional de crianças e adolescentes e os novos padrões de consumo: propagandas, embalagens e rótulos Nutritional guidance for children and adolescents and the new consumption patterns: advertising, packaging and labeling
OBJETIVO: Compilar e debater conhecimentos sobre os rĂłtulos, as embalagens e a divulgação e promoção de alimentos processados que progressivamente passam a compor a dieta da população infanto-juvenil. FONTES DE DADOS: Artigos nos bancos de dados eletrĂ´nicos, Medline e SciELO nos Ăşltimos dez anos, nas lĂnguas portuguesa e inglesa, utilizando os descritores "criança", "marketing", "hábitos alimentares", "televisĂŁo", "educação em SaĂşde". TambĂ©m foram consultados livros, textos recentes e artigos considerados relevantes para realização dessa revisĂŁo. SĂŤNTESE DOS DADOS: O artigo discute o marketing de alimentos, segundo os tĂłpicos: propagandas, embalagens e rĂłtulos. Quanto Ă publicidade televisiva, foi abordada sua influĂŞncia na formação dos hábitos alimentares infanto-juvenis, a qualidade nutricional dos alimentos veiculados e as alternativas para que pais e educadores possam lidar com os novos padrões de consumo. AlĂ©m disso, debateram-se as embalagens enquanto meios de comunicação entre fabricante e consumidor. Sobre os rĂłtulos, foram abordadas as novas regras da AgĂŞncia Nacional de Vigilância Sanitária a respeito da Rotulagem Nutricional ObrigatĂłria, bem como a importância da leitura adequada para a adoção de escolhas alimentares saudáveis. CONCLUSĂ•ES: Espera-se que este artigo seja instrumento de atualização dos profissionais da SaĂşde, proporcionando atuação mais incisiva no processo de educação em saĂşde e nutrição. Torna-se urgente a adoção de práticas preventivas com esclarecimento aos pais e familiares cujos filhos participam ativamente da sociedade de consumo, visando minimizar os efeitos deletĂ©rios da ingestĂŁo rotineira de alimentos obesogĂŞnicos.<br>OBJECTIVE: To debate knowledge on labeling, packaging, releases and promotion of processed foods that have been included progressively in the diets of children and adolescents. DATA SOURCE: On-line articles from Medline and SciELO database published over the last ten years in Portuguese and English using the keywords "child", "marketing", "eating habits", "television", "health education". Also, books, recent texts and articles considered relevant for the present review were included. DATA SYNTHESIS: The present article discusses the food marketing according to propaganda, packaging and labeling. This review also approaches the influence of TV advertising on building of children and adolescents' eating habits; the nutrition quality of advertised foods and alternatives that parents and teachers could use to deal with these new patterns of consumption. Additionally, it is discussed packaging as a communication tool between manufacturer and consumer. Regarding labeling, the "AgĂŞncia Nacional de Vigilância Sanitária" (Anvisa) new rules on Regulatory Nutritional Labeling as well as the importance of proper label reading for healthy choices are discussed. CONCLUSIONS: The present article is intended to be a tool for updating health professionals and encouraging them to act more effectively in health education and nutrition. It is urgent to adopt prevention practices enlightening parents and relatives whose children actively participate in the consumption society in order to minimize the harmful effects of the obesogenic foods routine ingestion