| Revista: | Brazilian journal of chemical engineering |
| Base de datos: | PERIÓDICA |
| Número de sistema: | 000308944 |
| ISSN: | 0104-6632 |
| Autors: | Souza, A. Gouveia de1 Santos, J.C. Oliveira2 Conceicao, M.M Silva, M.C. Dantas Prasad, S |
| Institucions: | 1Universidade Federal da Paraiba, Centro de Ciencias Exatas e da Natureza, Joao Pessoa, Paraiba. Brasil 2Universidade Federal da Paraiba, Centro de Ciencias Tecnologicas, Campina Grande, Paraiba. Brasil |
| Any: | 2004 |
| Període: | Jun |
| Volum: | 21 |
| Número: | 2 |
| Paginació: | 265-273 |
| País: | Brasil |
| Idioma: | Inglés |
| Tipo de documento: | Artículo |
| Enfoque: | Experimental, aplicado |
| Resumen en inglés | Recently, thermoanalytic methods have frequently been used in the characterization of oils and fats. In this work, thermoanalytic and kinetic parameters of sunflower oils, with and without antioxidants, were evaluated using thermogravimetry / derivative thermogravimetry and differential scanning calorimetry. The thermogravimetric profiles for the sunflower oils had similar characteristics, showing a level stretch indicative of stability up to about 200ºC. Thermal decomposition of these oils occurred in three stages, related to the decomposition of polyunsaturated, monounsaturated and saturated fatty acids, respectively. DSC curves show two events that characterize the polymerization and decomposition of triglycerides. The heat capacities of the sunflower oils, obtained by DSC, showed a good correlation and were dependent on the composition of fatty acids. The kinetic parameters, obtained by non isothermal thermogravimetry by the Coats and Redfern, Madhusudanan, Horowitz and Metzger and Van Krevelen methods, were dependent on the antioxidant used. Increasing the frying time produced a decrease in the onset of thermal decomposition temperature in the sunflower oils analyzed |
| Disciplines | Química |
| Paraules clau: | Química de alimentos, Aceite de girasol, Termogravimetría, Cinética química |
| Keyword: | Chemistry, Food chemistry, Sunflower oil, Thermogravimetry, Chemical kinetics |
| Text complet: | Texto completo (Ver HTML) |
