Can wine composition predict quality? A metabolomics approach to assessing Pinot noir wine quality as rated by experts

Wine grape production is increasingly vulnerable to freeze damage due to warming climates, milder winters, and unpredictable late spring frosts. Traditional methods for assessing frost damage in grapevines which combine fieldwork and meteorological data, are expensive, time-consuming, and labor-intensive. Remote sensing could offer a rapid, inexpensive way to detect frost damage at a regional scale. Remote sensing approaches were used to assess freeze damage in grapevines by evaluating satellite-derived vegetation indices (VIs) to understand the severity and spatial distribution of damage in several New York vineyards immediately after a frost event (May 17th-18th, 2023). PlanetScope 3m satellite images acquired before and after the freeze were used to map damage and measure changes in VIs for vineyards in the Finger Lakes region.

Winemaking areas recognized as protected designations of origin (PDOs) shape important economic, environmental and cultural values that are tied to closely defined geographic locations. To preserve wine products and wine-growing practices adopted in different PDOs these areas are strictly regulated by legal specifications. However, quality viticulture is increasingly under pressure from climate change, which is altering the local conditions of many winegrowing areas. Therefore, maintaining traditional wine products will require the adoption of tailored adaptation strategies, including possible changes in the legal regulation of protected wines. To this end, it is necessary to have a comprehensive knowledge on PDOs including their extension, products and allowed practices. While there have been efforts to build databases that summarize the characteristics for individual wine PDO areas and to quantify the related effects of climate change, much information is still included only in the official documentation of the EU geographical indication register and has never been collected in a comprehensive manner. With this study we aim at filling this gap by building a spatial inventory of European wine PDOs that supports decision making in viticulture in the context of climate change. To map and characterize European wine PDOs, we analysed their legal documents and extracted relevant information useful for climate change adaptation. The output consists of a comprehensive geographical dataset that identifies the boundaries of all 1200 European wine PDOs at unprecedented spatial resolution and includes a set of legally binding regulations, such as authorized vine varieties, maximum yields and planting density. The inventory will allow researchers to analyse the impacts of climate change on European wine PDOs and support decision makers in developing tailored adaptation strategies. This includes, among others, the evaluation of new vineyard site selection, the expansion of cultivated varieties or the authorization of irrigation in vineyards.

In neutral grapes, it is known that most aroma compounds are present as non-volatile
precursors.

In red wines, anthocyanins evolve during the wine-making process and ageing. They react with other compounds (such as vinylphenols, acetaldehyde, pyruvic acid…) to form a stable family of compounds called pyranoanthocyanins. Furthermore, the oxidation process can modify the anthocyanic profile of a red wine. It is also interesting to evaluate the occurrence of the different subclasses of pyranoanthocyanins and to characterize their chemical properties. The first objective of this study is to evaluate the occurrence of the different groups of pyranoanthocyanins in an oxidised Merlot wine by a centrifugal partition chromatography strategy. The second goal is to evaluate their relative impact in red wines from Bordeaux region by measuring their concentrations.

In 2020 one out of  eight wine bottles were filled with a flavoured wine-based beverage.