Impact of deficit irrigation strategies on terpene concentration in Gewürztraminer grapes

The European Landscape Convention (ELC, 2001) defined the landscape as the “part of a
territory as perceived by the population and resulting from the action of natural and/or human factors and their interrelationships”. Wine landscapes, protected or not under figures such as cultural landscapes or Cultural heritage, are a clear demonstration of this definition, denoting the interrelationships of the natural
environment and the action of the human, which modulates the territory to give the different wine
landscapes. This work was focused on the study of the effect of the human factors linked to the cultivation of the vine on the modification of the landscape.

Today the knowledge in terms of molecular composition of the colloidal matrix is ​​not enough in order to control its stability, according to the number of winemaking and wine stabilization processes. The physico-chemical processes during the winemaking change the composition and quantity of wine macromolecules. The goal today is to determine which analytical techniques will allow to discriminate these winemaking processes in order to better understand their impact on colloidal matrix stability as well as which molecules are responsible for its instabilities. METHODS: Wines obtained after conventional winemaking were subjected to different fining and chemical stabilization treatments. Different methods were used to investigate the wine macromolecular composition and stability after chemical stabilization, including quantitative and qualitative analyzes of total soluble polysaccharides by extraction under acidified ethanol, and by size exclusion separation as well as qNMR metabolomics. RESULTS: Observation of a slight difference at the quantitative level using classical analysis between the winemaking processes was observed as well as a strong discrimination by qNMR metabolomics.

Vine cultivar Mourvèdre is present all around the Mediterranean area and is interesting for its tannins and the specificity of its aromas.

The notion of terroir covers multiple components, from geology, pedology, geomorphology and climatology (Doledec, 1995), to aspects that are less well identified but which also intervene in the “typicality” of wines. This justifies the “zoning” approach (Moncomble and Panigaï, 1990) to define homogeneous areas, under the same agro-viticultural management and also identified at the product level (Morlat and Asselin, 1992).

The separation of different grape juice press fractions is an important step in the production of sparkling base wines. A complete press cycle for this style of wine is a series of pressure increases (squeezes) resulting in variations in juice composition during the press cycle. After alcoholic fermentation, wines obtained from grape juices also exhibit strong differences for numerous characteristics. Nevertheless, there is no statistical study of the impact of the press cycle on grape juices and wine colour/composition. So, the aim of this study (vintage 2018) was to investigate the changes in composition and colour parameters of Pinot noir and Pinot meunier grapes juices, as well as their corresponding wines, during the pressing cycle.