Authors
Advisor(s)
Abstract(s)
Este trabalho incidiu sobre o estudo do mecanismo de contaminação do vinho com 2,4,6-tricloroanisol (2,4,6-TCA) a partir da rolha de cortiça microaglomerada e o estudo de viabilidade da implementação do método de análise de 2-metoxi-3,5-dimetilpirazina (MDMP) por SPME-GC/MS. O primeiro estudo verificou a relação existente entre os níveis de contaminação com 2,4,6-TCA das rolhas de cortiça microaglomeradas de vários lotes (medido em termos de análise de grupo) e o nível de contaminação com 2,4,6-TCA (medido em termos de análise individual) encontrado em vinhos vedados com rolhas dos mesmos lotes. O método utilizado, neste estudo, para a quantificação de 2,4,6-TCA foi SPME-GC-MS. Ao fim de 3 meses, observou-se que os níveis de contaminação com 2,4,6-TCA dos vinhos eram idênticos aos encontrados na superfície da rolha em contacto com o vinho; esta contaminação ocorreu de forma relativamente rápida e não pareceu aumentar ao longo do tempo. Os níveis de contaminação com 2,4,6-TCA encontrados no vinho engarrafado são relativamente proporcionais aos níveis de contaminação com 2,4,6-TCA dos lotes de rolhas utilizados no ensaio.
O segundo estudo consistiu em desenvolver o método de análise de MDMP com base em literatura existente sobre o tema e implementar as condições presentes nessa literatura no SPME-GC-MS. O método de análise do composto referido foi optimizado; contudo, com um limite de quantificação muito superior ao limite de detecção sensorial deste mesmo composto em vinhos.
This work focused on studying the mechanism of contamination of wine with 2,4,6-trichloroanisole (2,4,6-TCA) from microaglomerated corks, and the feasibility study of the implementation of the method of analysis of 2-methoxy-3,5-dimethylpyrazine (MDMP) by SPME-GC/MS. The first study examined the relationship between the levels of contamination with 2,4,6-TCA from the microaglomerated corks of several batches (measured in terms of group analysis) and the level of contamination with 2,4,6-TCA (measured in terms of individual analysis) found in wine sealed with corks of the same batch. The method used in this study to quantify 2,4,6-TCA was SPME-GC-MS. After 3 months, it was observed that the levels of contamination with 2,4,6-TCA from wine were identical to those found on the surface of the cork in contact with wine, this contamination occurred relatively quickly and did not appear to increase over time. Levels of 2,4,6-TCA contamination found in bottled wine are relatively proportional to the levels of contamination with 2,4,6-TCA from cork lots used in the experiment. The second study was to develop the method of analysis of MDMP based on existing literature on the subject and to implement the conditions present in this literature in SPME-GC-MS. The method of analysis of the said compound was optimized, however with a quantification limit much higher than the detection limit of the same sensory compound in wine.
This work focused on studying the mechanism of contamination of wine with 2,4,6-trichloroanisole (2,4,6-TCA) from microaglomerated corks, and the feasibility study of the implementation of the method of analysis of 2-methoxy-3,5-dimethylpyrazine (MDMP) by SPME-GC/MS. The first study examined the relationship between the levels of contamination with 2,4,6-TCA from the microaglomerated corks of several batches (measured in terms of group analysis) and the level of contamination with 2,4,6-TCA (measured in terms of individual analysis) found in wine sealed with corks of the same batch. The method used in this study to quantify 2,4,6-TCA was SPME-GC-MS. After 3 months, it was observed that the levels of contamination with 2,4,6-TCA from wine were identical to those found on the surface of the cork in contact with wine, this contamination occurred relatively quickly and did not appear to increase over time. Levels of 2,4,6-TCA contamination found in bottled wine are relatively proportional to the levels of contamination with 2,4,6-TCA from cork lots used in the experiment. The second study was to develop the method of analysis of MDMP based on existing literature on the subject and to implement the conditions present in this literature in SPME-GC-MS. The method of analysis of the said compound was optimized, however with a quantification limit much higher than the detection limit of the same sensory compound in wine.
Description
Keywords
Rolha de cortiça microaglomerada 2,4,6-tricloroanisol Vinho 2-metoxi-3,5-dimetilpirazina Microagglomerated cork 2,4,6-trichloroanisole Wine 2-methoxy-3,5-dimethylpyrazine