RESUMO
The increase of disease borne pathogens in foods has promoted the use of new technologies in order to eliminate these pathogen microorganisms and extend the shelf-life of the foodstuffs. In particular, Cinnamon (Cinnamomum zeylanicum) contains an important number of pathogen microorganisms and it is frequently sterilized by gamma radiation. However, it is important to develop the detection methods for irradiated food in order to keep the dose control and also to analyze the radiation effects in their chemical property. This work reports (i) the photostimulated luminescence (PSL) detection of irradiated cinnamon and thermoluminescence (TL) detection of the inorganic polymineral fraction separated from this spice, and (ii) the proximate chemical analysis carried out on fat, protein and dietetic fiber contents. The detection limits using the PSL and TL methods were 500 Gy and 10 Gy, respectively, and the fat content was increased significantly with the gamma dose that could be related to the lipid oxidation in the cinnamon.
Assuntos
Cinnamomum zeylanicum/química , Cinnamomum zeylanicum/efeitos da radiação , Especiarias/análise , Especiarias/efeitos da radiação , Esterilização/métodos , Dosimetria Termoluminescente/métodos , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Doses de RadiaçãoRESUMO
Different spices such as turmeric, oregano, and cinnamon were γ-irradiated at 1 and 10 kGy. The electron paramagnetic resonance (EPR) spectra of the nonirradiated samples were characterized by a single central signal (g = 2.006), the intensity of which was significantly enhanced upon irradiation. The EPR spectra of the irradiated spice samples were characterized by an additional triplet signal at g = 2.006 with a hyperfine coupling constant of 3 mT, associated with the cellulose radical. EPR analysis on various sample pretreatments in the irradiated spice samples demonstrated that the spectral features of the cellulose radical varied on the basis of the pretreatment protocol. Alcoholic extraction pretreatment produced considerable improvements of the EPR signals of the irradiated spice samples relative to the conventional oven and freeze-drying techniques. The alcoholic extraction process is therefore proposed as the most suitable sample pretreatment for unambiguous detection of irradiated spices by EPR spectroscopy.
Assuntos
Celulose/química , Cinnamomum zeylanicum/química , Curcuma/química , Origanum/química , Especiarias/análise , Cinnamomum zeylanicum/efeitos da radiação , Curcuma/efeitos da radiação , Espectroscopia de Ressonância de Spin Eletrônica , Irradiação de Alimentos , Raios gama , Origanum/efeitos da radiação , Especiarias/efeitos da radiaçãoRESUMO
The effects of high dose γ-irradiation on six herbal medicines were investigated using gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). Herbal medicines were irradiated at 0-50 kGy with (60)Co irradiator. HPLC was used to quantify changes of major components including glycyrrhizin, cinnamic acid, poncirin, hesperidin, berberine, and amygdalin in licorice, cinnamon bark, poncirin immature fruit, citrus unshiu peel, coptis rhizome, and apricot kernel. No significant differences were found between gamma-irradiated and non-irradiated samples with regard to the amounts of glycyrrhizin, berberine, and amygdalin. However, the contents of cinnamic acid, poncirin, and hesperidin were increased after irradiation. Volatile compounds were analyzed by GC/MS. The relative proportion of ketone in licorice was diminished after irradiation. The relative amount of hydrocarbons in irradiated cinnamon bark and apricot kernel was higher than that in non-irradiated samples. Therefore, ketone in licorice and hydrocarbons in cinnamon bark and apricot kernel can be considered radiolytic markers. Three unsaturated hydrocarbons, i.e., 1,7,10-hexadecatriene, 6,9-heptadecadiene, and 8-heptadecene, were detected only in apricot kernels irradiated at 25 and 50 kGy. These three hydrocarbons could be used as radiolytic markers to distinguish between irradiated (>25 kGy) and non-irradiated apricot kernels.
Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Plantas Medicinais/química , Plantas Medicinais/efeitos da radiação , Cromatografia Líquida de Alta Pressão/métodos , Cinnamomum zeylanicum/química , Cinnamomum zeylanicum/efeitos da radiação , Citrus/química , Citrus/efeitos da radiação , Coptis/química , Coptis/efeitos da radiação , Flavonoides , Raios gama , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glycyrrhiza/química , Glycyrrhiza/efeitos da radiação , Estruturas Vegetais/química , Estruturas Vegetais/efeitos da radiação , Poncirus/química , Poncirus/efeitos da radiação , Prunus/química , Prunus/efeitos da radiação , Compostos Orgânicos Voláteis/análiseRESUMO
Nine spice and aromatic herb samples (i.e., basil, bird pepper, black pepper, cinnamon, nutmeg, oregano, parsley, rosemary, and sage) were gamma-irradiated at a dose of 10 kGy according to commercial practices. The effects of the disinfection treatment on the content of organic radicals and some nutrients (namely, vitamin C and carotenoids) in the samples were investigated by chromatographic and spectroscopic techniques. Irradiation resulted in a general increase of quinone radical content in all of the investigated samples, as revealed by electron paramagnetic resonance spectroscopy. The fate of these radicals after storage for 3 months was also investigated. The cellulose radical was clearly observed in a few samples. Significant losses of total ascorbate were found for black pepper, cinnamon, nutmeg, oregano, and sage, whereas a significant decrease of carotenoids content was observed for cinnamon, oregano, parsley, rosemary, bird pepper, and sage.
