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IVES 9 IVES Conference Series 9 Evolución de los compuestos fenólicos durante el envero y la maduración en la DO Tarragona

Evolución de los compuestos fenólicos durante el envero y la maduración en la DO Tarragona

Abstract

La evolución de los contenidos en las pieles de compuestos fenólicos (fenólicos totales, antocianos totales, antocianos individuales por HPLC, catequinas y proantocianidoles) a lo largo del envero y maduración han sido analizados en cepas de 7 años en 2 variedades, Cabernet Sauvignon y Tempranillo, en una zona correspondiente a la DO Tarragona. Asimismo, se efectuaron los análisis estándar (OIV) y de color para caracterizar los vinos obtenidos.
Los resultados muestran que la variedad Cabernet Sauvignon presenta una producción de antocianos por peso de baya superior a la que se obtiene con la variedad Tempranillo, a pesar que los niveles en compuestos fenólicos totales son similares para ambas. Los niveles de catequinas y proantociandinas son asimismo similares. Los análisis por HPLC muestran que ambas variedades presentan como antocianidina mayoritaria la malvidina durante toda la evolución. Sin embargo, hay diferencias notables en cuanto a la proporción de derivados acilados y al predominio del agente acilante (cumárico o acético).
En cuanto a los resultados de los análisis de los vinos, la variedad Cabernet Sauvignon produce vinos que alcanzan un grado alcohólico más elevado que Tempranillo. Los compuestos fenólicos y los antocianos se presentan en concentraciones más elevadas en Cabernet. Los rendimientos de cosecha indican mayores volúmenes en Tempranillo, variedad de racimo más grande que Cabernet Sauvignon. Si se considera el contenido en compuestos fenólicos alcanzado en Cabernet Sauvignon y se compara con resultados procedentes de otra zona vitícola con características edafoclimáticas distintas se observan diferencias. Debe destacarse el efecto del mesoclima en Tarragona, más lluvioso en verano, que conduce a producciones demasiado elevadas para conseguir una mayor concentración tánica: las condiciones climáticas durante el período estival en Tarragona no permiten alcanzar el contenido máximo en polifenoles.

DOI:

Publication date: February 24, 2022

Issue: Terroir 2000

Type: Article

Authors

Josep Valls, Miriam Lampreave, Montse Nadal and Lluís Arola

Unitat d’Enologia del Centre de Referència en Tecnologia d’Aliments de la Generalitat de Catalunya. Dept. de Bioquímica i Biotecnologia. Facultat d’Enologia de Tarragona, Universitat Rovira i Virgili. C. Ramón y Cajal, 70, 43005 Tarragona

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IVES Conference Series | Terroir 2000

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