| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 5.62 MB | Adobe PDF |
Authors
Advisor(s)
Abstract(s)
O presente trabalho encontra-se integrado no âmbito da disciplina Dissertação/Estágio do Mestrado em Engenharia Química – ramo Qualidade, do Instituto Superior de Engenharia do Porto. O estágio foi realizado na empresa Super Bock Group, SA - líder nacional na área de bebidas. O estágio decorreu no Laboratório Central e teve por objetivo o desenvolvimento e implementação de métodos de análise de vinhos brancos e sangrias por Espetroscopia de Infravermelho com Transformada de Fourier. Foi adquirido o Thermo Scientific Nicolet iS5 FTIR com o objetivo de efetuar os ensaios da determinação do teor alcoólico, da acidez volátil acética, da acidez total tartárica, dos açúcares redutores e totais e da massa volúmica, em dois tipos de amostras – vinhos brancos e sangrias. Para a construção das retas de calibração dos métodos respetivos, utilizaram-se vinhos naturais padronizados, incluindo vinhos brancos, rosés e tintos, adquiridos na Comissão de Vinhos Verdes, e vinhos sintéticos de referência da marca TITRIVIN. Os métodos estudados foram avaliados pelos parâmetros de calibração, de precisão intermédia, de repetibilidade e de veracidade. No caso da determinação da repetibilidade, esta foi aceitável para os métodos de análise de teor alcoólico, massa volúmica e acidez total para as amostras de vinho tinto e de vinho branco. Os parâmetros de acidez volátil e teor de açúcares redutores tiveram uma repetibilidade aceitável para as amostras de vinho tinto e o parâmetro de açúcares totais para as amostras de vinho branco. Na determinação da precisão intermédia verificou-se a mesma situação. Concluiu-se que, após o fim de período de estágio o equipamento em estudo, encontrava-se preparado para a aplicação dos métodos de análise de teor alcoólico, massa volúmica, acidez total e volátil, teor de açúcares totais e redutores, nas amostras de vinho. No caso de sangria, é necessário construir retas de calibração independentes, com recurso à soluções-padrão de sangria, uma vez que, a matriz destas amostras difere significativamente das amostras de vinho.
The present study is integrated in the scope of the Dissertation/Internship of the Master’s in Chemical Engineering – Quality branch of the Porto Superior Institute of Engineering. The internship was fulfilled in Super Bock Group, SA– national leader in the beverages department. The internship occurred in the Central Laboratory and had the goal of development and implementation of methods of analysis of white wines and sangrias by Infrared Spectroscopy with Fourier transform. The Thermo Scientific Nicolet iS5 FTIR was purchased for determination of alcohol content, volatile acetic acidity, total tartaric acidity, reducing and total sugars and density in two types of samples – white wine and sangrias. For the construction of the calibration lines, standardized natural wines were used, including white, rose ad red wines of the Comissão de Vinhos Verdes and synthetic reference wines of the TITRIVIN brand were used. The studied methods were evaluated by calibration parameters, intermediate accuracy, repeatability and veracity. In case of determination of repeatability, was acceptable for methods of analysis of alcoholic strength, density and total acidity for red wine and white wine samples. The parameters of volatile acidity and reducing sugar content had an acceptable repeatability for the red wine samples and the total sugars parameter for the white wine samples. In determining the intermediate accuracy, the same situation was observed. In the end of the internship period, the equipment under study was ready to use in the wine analysis mentioned methods. However, it is necessary to create independent calibration lines for Sangria using standard solutions,since the matrix of these samples significantly differs from the wine samples.
The present study is integrated in the scope of the Dissertation/Internship of the Master’s in Chemical Engineering – Quality branch of the Porto Superior Institute of Engineering. The internship was fulfilled in Super Bock Group, SA– national leader in the beverages department. The internship occurred in the Central Laboratory and had the goal of development and implementation of methods of analysis of white wines and sangrias by Infrared Spectroscopy with Fourier transform. The Thermo Scientific Nicolet iS5 FTIR was purchased for determination of alcohol content, volatile acetic acidity, total tartaric acidity, reducing and total sugars and density in two types of samples – white wine and sangrias. For the construction of the calibration lines, standardized natural wines were used, including white, rose ad red wines of the Comissão de Vinhos Verdes and synthetic reference wines of the TITRIVIN brand were used. The studied methods were evaluated by calibration parameters, intermediate accuracy, repeatability and veracity. In case of determination of repeatability, was acceptable for methods of analysis of alcoholic strength, density and total acidity for red wine and white wine samples. The parameters of volatile acidity and reducing sugar content had an acceptable repeatability for the red wine samples and the total sugars parameter for the white wine samples. In determining the intermediate accuracy, the same situation was observed. In the end of the internship period, the equipment under study was ready to use in the wine analysis mentioned methods. However, it is necessary to create independent calibration lines for Sangria using standard solutions,since the matrix of these samples significantly differs from the wine samples.
Description
Keywords
FTIR Vinho branco e sangria Implementação de métodos Teor alcoólico Massa volúmica Acidez total Acidez volátil Açúcares totais Açúcares redutores White wine and sangria Method implementation Alcoholic strength Density Total acidity Volatile acidity Total sugars Reducing sugars