Abstract
Climate change is having a profound effect on viticulture by altering the conditions under which vines grow, leading to increased water stress and earlier harvests, which in turn affect the quality and character of wines [1]. Climatic variations also influence the concentration of phenolic compounds, essential for wine structure and colour, forcing winegrowers to adapt their practices [2]. In addition, diseases such as powdery mildew, downy mildew and grey rot, favoured by these climatic changes, threaten harvests and wine quality [3]. The excessive use of pesticides to combat them presents significant environmental and health challenges, negatively affecting biodiversity and human health. Faced with these challenges, winegrowing is moving towards more sustainable approaches, such as biological control, the use of disease-resistant/tolerant grape varieties and preventive techniques [4]. New disease-resistant grape varieties promise to produce quality wines while significantly reducing pesticide use. Studies indicate that wines from these varieties have phenolic, anthocyanin, and volatile profiles comparable to traditional Vitis vinifera wines while also displaying distinctive compositional differences [5].
Our global project, carried out jointly by the University of Bordeaux and the University of Bolzano, aims to establish a comparison of French (Bordeaux & Pays d’Oc) and Italian (South Tyrol) wines from different cultivars (local and international), terroirs and different conditions (organic/conventional wines) and develop interlaboratory comparisons of targeted and non-targeted analysis methods based on the use of NMR and MS, coupled with HPLC and GC. An initial targeted and non-targeted profiling of 61 commercial monovarietal wines from Pays d’Oc (France), using UHPLC-HRMS/MS has already been carried out. The targeted analysis was conducted using a calibration curve of over 45 polyphenols, while the untargeted approach was based on a Full Scan HRMS acquisition with data-dependent fragmentation. The initial results showed a clear discrimination between wines based on the grape variety and cultural practices.
The same strategy is now being used on an additional dataset of 59 monovarietal wines from South Tyrol (Italy) coupled with HS-SPME-GCxGC-ToF/MS for their volatile profile and HPLC-QQQ-MS for anthocyanins, polyphenols and proanthocyanidins profiles. These multi-omics approaches should provide new knowledge and methodologies to discriminate wines based on their cultural practices [6].