title: Thermal and spectroscopic studies of the antioxidant food additive propyl gallate.
abstract: Literature mentions propyl gallate (PG) as a non-toxic synthetic antioxidant that can be used as a food additive due to its high tolerance to heat. It is important to understand the thermal properties and to identify the decomposition products of this substance, since it has been reported to be thermally stable at temperatures as high as 300 °C. Simultaneous thermogravimetry-differential thermal analysis (TG-DTA), differential scanning calorimetry-photovisual (DSC-photovisual), coupled thermogravimetry-infrared spectroscopy (TG-FTIR) analyses and spectroscopic techniques were used to study the food additive PG. The TG-DTA curves, which were performed with the aid of DSC-photovisual, provided information concerning the thermal stability and decomposition profiles of the compound. From the TG-FTIR coupled techniques, it was possible to identify n-propanol as a possible volatile compound released during the thermal decomposition of the antioxidant. A complete spectroscopic characterization in the ultraviolet, visible, near and middle infrared regions was performed in order to understand the spectroscopic properties of PG.
authors.affiliation: UNESP - Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260, Brazil.
authors.forename: D A
authors.initials: DA
authors.lastname: Gálico
authors.affiliation: UNESP - Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260, Brazil.
authors.forename: C V
authors.initials: CV
authors.lastname: Nova
authors.affiliation: UNESP - Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260, Brazil.
authors.forename: R B
authors.initials: RB
authors.lastname: Guerra
authors.affiliation: UNESP - Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260, Brazil. Electronic address: gilbert@fc.unesp.br.
authors.forename: G
authors.initials: G
authors.lastname: Bannach
mesh_terms: D000975:Antioxidants; D002152:Calorimetry, Differential Scanning; D005503:Food Additives / Q000032:analysis*; D011435:Propyl Gallate / Q000032:analysis*; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D000975:Antioxidants; D005503:Food Additives; D011435:Propyl Gallate
keywords: Coupled TG-FTIR; DSC-photovisual; Propyl gallate; Spectroscopic studies; Thermal behavior