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IVES 9 IVES Conference Series 9 Effects of soil and climate on wine style in Stellenbosch: Sauvignon blanc

Effects of soil and climate on wine style in Stellenbosch: Sauvignon blanc

Abstract

[English version below]

Une étude a été menée pendant neuf ans sur deux vignes non-irriguées de Sauvignon blanc commercialisés, plantées à différentes localités (A et B) dans le district de Stellenbosch. Deux parcelles expérimentales, situées sur deux formations géologiques différentes, ont été identifiées au sein de chaque vignoble. A chaque localité une des formations pédologiques montre des signes d’humidité en profondeur, tandis que l’autre est relativement sèche. Malgré leur proximité géographique (9 km), le méso-climat diffère entre les deux localités, principalement en raison de l’altitude, A étant situé à 413 m et B à 148 m d’altitude. La température maximale de février est 1.9ºC plus basse en A qu’en B, les températures nocturnes sont aussi les plus basses en A. Les raisins de la localité la plus fraîche (A) sont généralement récoltés deux semaines plus tard que ceux de la localité la plus chaude (B). A la localité la plus fraîche, la maturation est aussi affectée par la formation pédologique : les raisins issus du sol le plus sec ont été vendangés approximativement une semaine avant ceux ceux issus du sol plus humide. Cependant la maturation n’a pas été affectée par le sol à la localité la plus chaude. A la localité la plus fraîche, les vins issus du sol plus humide révèlent généralement un caractère végétatif frais prédominant (herbacé, poivre vert, eucalyptus, menthe) et ceux issus du sol plus sec des caractéristiques de légumes cuits (haricots verts, asperges, olive, artichaut) et de fruits. Le style de vin n’a pas été affecté par la formation pédologique à la localité la plus chaude oú les caractères de fruits tropicaux dominent. Les résultats suggèrent que le style du vin de Sauvignon blanc de Stellenbosch n’est pas seulement affecté par le climat, mais aussi par le sol.
A nine-year study was carried out in two non-irrigated, commercial Sauvignon blanc vineyards, grown at different localities (A and B) in the district of Stellenbosch. Two experimental plots, representing different soil forms, were identified within each vineyard. At both localities one of the soil forms showed signs of wetness with depth, while the other one was relatively dry. Despite their geographic proximity (9 km), meso-climate differed between the two localities, largely on account of A being situated at higher altitude (413 m) than B (148 m). Maximum temperature for February was 1.9ºC lower for A than for B, while night temperature was also lowest at A. Grapes at the cooler locality (A) were generally harvested two weeks later than those at the warmer one (B). At the cooler locality ripening was also affected by soil form, with grapevines on the drier soil being harvested approximately one week earlier than those on the wetter soil. Ripening was not affected by soil form at the warmer locality. At the cooler locality, wine from the wetter soil generally exhibited a prominent fresh vegetative character (grass, green pepper, eucalyptus, mint), in comparison to cooked vegetative (green beans, asparagus, olive, artichoke) and fruity characteristics for the one from the drier soil. Wine style was not affected by soil form at the warmer locality, with tropical fruit character being dominant. Results suggested that the style of Sauvignon blanc wines from Stellenbosch is not only affected by climate, but also by soil form.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

W.J. Conradie (1)* and M.P. Olivier (1)**

(1) ARC Infruitec-Nietvoorbij, Private Bag X5026, 7599 Stellenbosch, Republic of South Africa

* Present address: Department of Soil Science, University of Stellenbosch, 7600 Stellenbosch, Republic of South Africa
** Presenting author

Contact the author

Keywords

Soil, climate, wine style, Sauvignon blanc, Stellenbosch, South Africa

Tags

IVES Conference Series | Terroir 2004

Citation

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