| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 4.06 MB | Adobe PDF | |||
| 1.74 KB | License |
Advisor(s)
Abstract(s)
O presente relatório foi feito no âmbito da unidade curricular “Dissertação/Estágio” do Mestrado em Engenharia Química – Ramo Qualidade, na Symington Family Estates, Vinhos, S.A.. Esta dissertação teve como objetivo a definição e validação do método de quantificação de 2,4,6-tricloroanisol (2,4,6-TCA) em aguardente/brandy por microextração em fase sólida (SPME) no headspace (HS) e posterior análise por cromatografia gasosa com detetor de captura de eletrões (GC-ECD). Foram realizados estudos comparativos com métodos já em prática no laboratório, desenvolvidos para outras matrizes, e estudos de otimização das condições de extração de aguardente 40% (v/v), comparando as respostas obtidas para as diferentes condições de trabalho SPME. Para além disto, foi também estudado o fator de diluição da aguardente. Concluiu-se que seriam utilizadas as mesmas condições de trabalho do método DOC (Vinho do Porto), utilizando curvas de calibração diferentes, próprias de aguardente. Assim, obtiveram-se resultados satisfatórios com 25 minutos de tempo de extração, 5 minutos de dessorção, um teor alcoólico de 6,5% (v/v), obtido por diluição, e utilizando 50 µL de solução de 2,3,6-TCA (padrão interno). Para validar o método foram realizados estudos de linearidade, da gama de trabalho, limiares analíticos, precisão, exatidão e incerteza. Para a gama de trabalho de 2,0 ng/L a 8,0 ng/L, os resultados demonstram uma boa linearidade, com coeficientes de determinação (R2) superiores a 0,995, um limite de deteção de 0,13 ng/L e um limite de quantificação de 0,39 ng/L. Os testes realizados com amostras de Brandy 30% e 43% (v/v) demonstraram que o método é eficaz na análise de todas as bebidas espirituosas existentes na empresa.
This report was carried out in the internship of the curricular unit “Dissertation/Internship” of the Master’s in Chemical Engineering – Quality, at Symington Family Estates, Vinhos, S.A.. The main objective of this dissertation was to define and validate a method for the quantification of 2,4,6-Trichloroanisol (2,4,6-TCA) in brandy by headspace-solid phase microextraction (HS-SPME) and analysis by gas chromatography with electron capture detection (GC-ECD). Comparative studies on other methods currently in use at the lab, for other matrices, and on the optimization of the extraction conditions were performed, comparing the results obtained for different SPME work conditions. Besides this, the amount of dilution necessary for the analysis of brandy was studied. It was concluded that the same work conditions for the DOC method (Port wine) would be used, using different calibration curves, for brandy. This way, satisfactory results were obtained with 25 minutes of extraction time, 5 minutes of desorption, an alcoholic content of 6.5% (v/v), after dilution, and using 50 µL of 2,3,6-Trichloroanisol (internal standard). The method validation followed studies of linearity, work range, analytical thresholds, precision, accuracy, and uncertainty. For the work range of 2.0 ng/L to 8.0 ng/L, the results have shown good linearity, with coefficients of determination (R2) higher than 0.995, a detection limit of 0.13 ng/L and a quantification limit of 0.39 ng/L. The tests performed on other brandy samples with 30% and 43% (v/v) demonstrated that the method is effective in analyzing all the spirits existing in the company.
This report was carried out in the internship of the curricular unit “Dissertation/Internship” of the Master’s in Chemical Engineering – Quality, at Symington Family Estates, Vinhos, S.A.. The main objective of this dissertation was to define and validate a method for the quantification of 2,4,6-Trichloroanisol (2,4,6-TCA) in brandy by headspace-solid phase microextraction (HS-SPME) and analysis by gas chromatography with electron capture detection (GC-ECD). Comparative studies on other methods currently in use at the lab, for other matrices, and on the optimization of the extraction conditions were performed, comparing the results obtained for different SPME work conditions. Besides this, the amount of dilution necessary for the analysis of brandy was studied. It was concluded that the same work conditions for the DOC method (Port wine) would be used, using different calibration curves, for brandy. This way, satisfactory results were obtained with 25 minutes of extraction time, 5 minutes of desorption, an alcoholic content of 6.5% (v/v), after dilution, and using 50 µL of 2,3,6-Trichloroanisol (internal standard). The method validation followed studies of linearity, work range, analytical thresholds, precision, accuracy, and uncertainty. For the work range of 2.0 ng/L to 8.0 ng/L, the results have shown good linearity, with coefficients of determination (R2) higher than 0.995, a detection limit of 0.13 ng/L and a quantification limit of 0.39 ng/L. The tests performed on other brandy samples with 30% and 43% (v/v) demonstrated that the method is effective in analyzing all the spirits existing in the company.
Description
Keywords
2,4,6-TCA 2,3,6-TCA Brandy Aguardente Cromatografia gasosa HSSPME Validação Método Gas Chromatography Validation Method