Terroir 2014 banner
IVES 9 IVES Conference Series 9 International Terroir Conferences 9 Terroir 2014 9 Grape growing soils, topographic diversity 9 The effect of pedoclimatic conditions on the yeast assimilable nitrogen concentration on white cv. Doral in Switzerland

The effect of pedoclimatic conditions on the yeast assimilable nitrogen concentration on white cv. Doral in Switzerland

Abstract

Aims: Agroscope investigated the efficiency of nitrogen fertilization via foliar urea application at veraison with the aim of raising the YAN (yeast assimilable nitrogen) content in the musts. The observations were conducted on the white grapevine cultivar Doral (Chasselas x Chardonnay) in several pedoclimatic conditions of the Leman wine region, Switzerland, in the years 2012 and 2013. Knowing that the YAN in must plays a key role in wine quality, the aim was finding the main parameters affecting the final YAN level in order to better control them.

Methods and results: Five plots of Doral were chosen over 80 km of vineyards. Pedologic profiles were realised. Vegetal materials, date of plantation and cultivation practices were kept constant for comparison purposes. Each plot was divided in two treatments of 60 vines each: a control treatment and a nitrogen fertilized treatment (20 kg/ha as foliar urea applied at veraison). Phenological development, nitrogen status and grape maturation of vines were monitored. 50 kg of grapes were harvested in each treatment. Musts were analysed after crushing and then vinified separately using a standard protocol. Wines were then analysed and tasted by an expert panel. Strong vintage and site effects were pointed out. YAN levels in musts were significantly affected by nitrogen fertilization. YAN gain in must was 56 ± 31 mg/L average. YAN gain between control and fertilised treatments was globally higher in 2013. Some sites consistently presented higher gains. The soil seemed to mainly affect vine nitrogen status by its water holding capacity and its effective root zone depth. No correlation could be established between initial leaf N content and the variation of YAN gain. YAN in must was the parameter that best explained the positive variations in wine sensory characteristics, although not always significant.

Significance and impact of the study: This work has so far confirmed that YAN level in must, in relation to climate and soil characteristics, contributes to the terroir effect on the wine quality. YAN concentration is clearly influenced by pedoclimatic conditions (i.e. vintage and site). The study is ongoing in 2014 in order to better understand which parameters in the vineyard we could optimize with the aim of raising up the YAN level in musts.

DOI:

Publication date: July 31, 2020

Issue: Terroir 2014

Type: Article

Authors

Thibaut VERDENAL (1), Vivian ZUFFEREY (1), Stéphane BURGOS2, Johannes RÖSTI1, Fabrice LORENZINI3, Agnès DIENES-NAGY3, Katia GINDRO1, Jean-Laurent SPRING1 and Olivier VIRET1

(1) Institute for Plant Production Sciences, Agroscope, 1009 Pully, Switzerland
(2) Changins, 1260 Nyon, Switzerland 
(3) Institute for Food Sciences, Agroscope, 1260 Nyon, Switzerland 

Contact the author

Keywords

terroir, yeast assimilable nitrogen YAN, leaf urea fertilisation, wine quality, terroir

Tags

IVES Conference Series | Terroir 2014

Citation

Related articles…

From a local to an international scale: sensory benchmarking of PDO wines. Quincy and Reuilly PDO wines (Sauvignon blanc) as a case study (France)

In a collective marketing strategy, the Protected Designation of Origin (PDO) can be used as a quality indicator. To highlight terroir specificities, it is useful to know how the wines are positioned on the local, national or international market from a sensory point of view. This is especially true for a comparison of varietal wines (e.g. Sauvignon blanc). We focus on the case of two closed Loire Valley PDO (France): Quincy and Reuilly. Three distinct tastings were organized. Firstly, at the local level comparing the 2 PDO (11 and 9 wines, 17 professional assessors); secondly at a regional level adding 3 closed PDO: Menetou-Salon, Sancerre and Pouilly-Fumé (3 wines per PDO, 16 assessors) and thirdly at an international level comparing these 5 PDO with Sauvignon Blanc wines coming from South Africa, New Zealand and Chile (1 to 3 wines per PDO, 19 assessors). All the wines were from the 2019 vintage and were considered to have a traditional elaboration process without contact with oak. A sensory descriptive analysis was performed using an aroma wheel allowing to combine a Check-All-That-Apply methodology, often used in sensory benchmarking, with a hierarchical structuration of the attributes. The aim is to facilitate data acquisition in a professional context without common training, to consider the hierarchical relationships among the attributes during the data analysis and to be able to characterize wines with a large range of sensorial variability. We use univariate, multivariate and clustering analyses. Similarities and differences between Quincy and Reuilly PDO wines and other Sauvignon blanc wines were identified. Specific attributes can distinguish the two PDO and different proximities exist with other local PDO, while clear differences were observed compared to international wines. Our study contributes to propose and discuss a method to do a wine sensory benchmarking highlighting sensory specificities linked to origin.

Monitoring small-scale alcoholic fermentations using a portable FTIR-ATR spectrometer and multivariate analysis

Although some wine production processes still rely on post-production evaluation and off-site laboratory analysis, the new winemaking industry is aware of a need for a better knowledge of the process to improve the properties of the final product. Thus, more and more wineries are interested in incorporating quality-by-design (QbD) strategies instead of postproduction testing because of the possibility to early detect deviations in fermentation or any other wine process. This would allow to detect unwanted situations and eventually to ‘readjust’ the process, thus minimizing rejects.

The impact of vine pruning methods on physiological development and health condition of Vitis vinifera

This project aims on monitoring the plant development and comparison of the effects of various training systems on vine fertility and physiological processes.

The impact of delayed grapevine budbreak on lemberger wine sensory compounds under variable weather conditions

Spring freeze events threaten grape production globally. As grape buds emerge from dormancy in spring, freezing temperatures have the potential to damage green tissues, decreasing yield potential and compromising fruit quality by harvest.

Characterization of “territoires” throughout the production of wines obtained with withered grapes: the cases of “Terra della Valpolicella” (Verona) and “Terra della Valle del Piave” (Treviso) in Northern Italy

Dans la définition et la description d’un “territoire” (“terra” en italien), avec les facteurs du milieu et génétiques, un rôle important est joué par ceux agronomiques, techniques et de culture qui contribuent à caractériser le produit d’une zone spécifique.