Terroir 2016 banner
IVES 9 IVES Conference Series 9 Tasting soils in Pinot noir wines of the Willamette valley, Oregon

Tasting soils in Pinot noir wines of the Willamette valley, Oregon

Abstract

The conventional wisdom of vintners is that alkalinity, and thus less sour and more rounded taste, are enhanced in wine and grapes challenged by low-nutrient soils. A common thread here is pH, an objectively measurable variable that is both a part of wine taste and a proxy for soil fertility. The role of low-pH soils is supported by metadata on Oregon wines from different soils in the Willamette Valley of Oregon, USA, which show significant inverse correlations between minimum pH of the soil and pH of finished Pinot Noir wine. There is also a direct correlation between depth of clayey horizons and pH of the finished wine.

The minimum pH of these soils is near the base of the clayey (Bw or Bt) horizon and is inversely correlated with depth of the clayey horizon. Low soil pH is found in thick middle Pleistocene soils of bedrock (Jory, Willakenzie, Laurelwood, and Bellpine soil series) and high soil pH in thin soils on late Pleistocene and Holocene Missoula Flood deposits and loess (Hazelair, Woodburn, and Chehulpum soil series). Similar relationships are found between soil pH or depth and the pH of grapes at harvest, which is lower and more varied than pH in finished wine. These relationships are especially notable in years of good harvest, but obscured by wine- making techniques in years of poor harvest. Good harvest years are not necessarily vintages esteemed by wine connoisseurs, which are more strongly correlated with low October precipitation.

DOI:

Publication date: June 23, 2020

Issue: Terroir 2016

Type: Article

Authors

Gregory J. Retallak (1) and Scott F. Burns (2)

(1) Dept. of Geological Sciences, University of Oregon, Eugene, Oregon 97403, USA
(2) Dept. of Geology, Portland State University, Portland, Oregon 97207, USA

Contact the author

Keywords

Pinot Noir, mineralogy, wine chemistry, soil chemistry, sensory analysis

Tags

IVES Conference Series | Terroir 2016

Citation

Related articles…

A applied viticultural zoning, based on the “secteurs de la reference” methodology, in the Cognac vineyard (France)

Dans les Charentes, en réponse à une crise de production du vignoble destiné à la production de Cognac, un plan de diversification viticole pour des vins de pays de qualité est mis en place. Il nécessite une connaissance des sols et de leurs caractéristiques viticoles pour orienter le choix des types de vins et adapter l’itinéraire technique de production.

Late pruning, an alternative for rainfed vine varieties facing new climatic conditions

In Chile there is a dry farming area known as a traditional wine region, where varieties brought by the Spanish conquerors still persist. These varieties, in general, are cultivated under traditional systems, with low use of technical and economic resources, and low profitability for their grapes and wines. In this region, as in other wine grape growing areas, climatic conditions have changed significantly in recent decades. In particular, the occurrence of spring frosts, when bud break has already begun, have generated significant losses for these growers.

Evaluation of intra-vineyard spatial and temporal variability of leaf area index using multispectral images obtained by satellite (Landsat 8, Sentinel-2) and unmanned aerial vehicle platforms

Estimation of vineyard leaf area index (LAI) is an important aspect for the winegrowers. However, tracking and monitoring are difficult tasks due to time constraints. Satellite and unmanned aerial vehicle (UAV) imaging have become a practical monitoring method for LAI. Nevertheless, for a proper LAI determination, the image’s spatial resolution is a key factor, since low-resolution images are incapable of distinguishing between adjacent vines due to the large area covered in each pixel, this leads to misinterpretation or generalisation of vineyard information.

Aroma diversity of Amarone commercial wines

Amarone is an Italian red wine produced in the Valpolicella area, in north-eastern Italy. Due to its elaboration with withered grapes, Amarone is a rather unique example of dry red wine. However, there is very limited data so far concerning the volatile composition of commercial Amarone wines, which also undergo a cask aging of 2-4 years before release.

Ten grapevine rootstocks: effects on vegetative development, production and grape quality of cv. Mencia in the d.o. Bierzo (Spain)

Grapevine rootstock is basic to achieve good adaptation of the vine to ground and environment.