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IVES 9 IVES Conference Series 9 Territorial delimitation of viticultural “Oltrepo Pavese (Lombardy)” using grape ripening precocity

Territorial delimitation of viticultural “Oltrepo Pavese (Lombardy)” using grape ripening precocity

Abstract

[English version below]

L’Oltrepò Pavese est une zone de collines de la Lombardie, région située au nord de l’Italie avec un vignoble qui s’étend sur près de 15 000 ha. Cette zone représente la plus grande aire de production de la région et une des A.O.C. les plus étendues de tout le pays. Les cépages les plus cultivés, même historiquement, sont autochtones : la Barbera et la Croatina utilisés pour la production de vin rouge «Oltrepò» et le Pinot noir pour la production de vins mousseux. Pour le zonage viticole de cette A.O.C., il a été pris en considération: le climat, les sols, les caractéristiques viti-vinicoles. L’étude pédologique effectuée sur le vignoble a permis de réaliser une carte des sols à l’échelle 1/25000. Pour l’étude viticole, il a été choisi 80 parcelles de références représentatives des sols, du climat et des conditions agronomiques. Sur toutes les parcelles pendant trois ans (1999, 2000, 2001), des données sur la production, sur la vigueur, sur la maturation et sur la composition des moûts ont été récoltées. Pendant la vendange, un échantillon représentatif de raisin a été récolté pour les microvinifications de chaque parcelle. Les vins ont été étudiés chimiquement et aussi soumis à des tests d’analyse sensorielle. L’approche multidisciplinaire a permis de caractériser l’appellation en zone adaptée à produire un vin de base Pinot noir et une zone différente plus apte à la production d’un vin rouge moderne et de qualité. Avec l’élaboration statistique des données cumulées des trois années des courbes de maturation, il a été possible de subdiviser les parcelles en classe de précocité et observer qu’avec une véraison plus précoce correspondrait aussi une meilleure accumulation des sucres au moment de la récolte. Pour les vins rouges, les facteurs influençant le plus la précocité se trouvent être l’altitude, la capacité de drainage des sols et la P.A.R., alors que pour le pinot noir l’altitude et la composition des sols jouent un rôle plus important. Des différences statistiques significatives se sont révélées sur les paramètres végétatifs, productifs et qualitatifs des moûts, sur le contenu polyphénolique du raisin et sur les profils chimiques et sensoriels des vins produits par microvinification.

Oltrepò Pavese is a hilly area of Lombardy, a region located in northern Italy with a vineyard surface of approximately 15.000 ha. It represents the widest viticultural area of all the region and one of the most extended zones of Origin’s Denomination of all the country. The mainly grown varieties, also from the historical point of view, are the autochthonous Barbera and Croatina used for the production of the Red wine Oltrepo and Pinot noir used for the sparkling wine. For the viticultural zoning of the area, climate, soils, viticulture and enological properties have been characterised. The pedological survey carried out in the vineyards allowed to produce a soil map on a scale of 1 :25.000. For the viticultural survey, 80 trial sites, representative of the soil, climate and agronomic condition have been chosen. In all the site for three years (’99, ’00 and 2001) grapevine yield, vegetative growth, maturation curves and must composition were detected. At vintage, an adequate grape sample was gathered for microvinification. Wines were evaluated both by chemical and sensorial analysis. A multidisciplinary approach allowed to characterise the area in different zones adapted to produce sparkling Pinot noir wine and in zones of different suitability in order to produce a modern style premium red wine. By a statistical data processing of the three years maturation curves it was possible to subdivide the vineyards in precocity classes and to observe that an earlier veraison generally corresponded also to an high sugar accumulation at the moment of grape harvest. For red wines the mainly influencing factors regarding the precocity turned out to be altitude, the soil ability to water-drainage and the P.A.R. availability (photosynthetically active radiation) while for Pinot noir altitude and soil texture played the most important role. Statistical significant differences in growth, yield and quality have been found on musts composition, on polyphenols content of the grapes and on the chemical and sensorial profile of wines produced by microvinifications.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

Brancadoro L., Toninato L., Tamai G., Failla O., Peluso F., Mariani L., Minelli R., Scienza A.

Université di Milano – Dipartimento di Produzione Vegetale – Via Celoria 2, 20133 Milano, Italy

Contact the author

Keywords

analyse sensorielle, capacité de drainage, courbes de maturation, microvinification, P.A.R.
maturation curves, microvinifications, P.A.R., sensorial analysis, water-drainage

Tags

IVES Conference Series | Terroir 2002

Citation

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