Effet de l’ombrage respectif des ceps et des grappes de Muscat sur leurs teneurs en composés volatils libres et glycosyles et en précurseurs d’aromes carotenoïdiques

A rapid and reproducible microwave (MW)-assisted acid digestion protocol was developed to determine the elemental composition of grapevine bark samples using ICP-MS.

This study was performed on Chasselas wine to assess the impact of exposure to wine light according to several glass color of bottles. The aim was to highlight any differences whether from an organoleptic or analytical point of view depending on the color. For this, four different shades were compared, dead leaf, green, cinnamon and transparent. A control, not treated with light, was also included in the study. Several tests were carried out with different exposure times in boxes as well as in stores. The bottles were exposed 7 days, 4 days as well as 2 days in box but also 7 days in store. At the end of each test the different modalities were tasted by an expert panel in order to observe any differences between the tint modalities. As a result of these experiments, it was observed that organoleptic differences significant appeared after 2 days of exposure, in particular on the olfactory notes of the reduction. The transparent modality was seen to be significantly more intense on reduction scores compared to other modalities, including the witness in particular. These differences were also observed during all the tests even that of 7 days of exposure in store where we would have thought that there would be no difference. Overall, the control and cinnamon modalities are generally perceived to have more intense notes on the fruity, floral descriptors but less intense for reduction than the transparent shade. For the dead leaf and green modalities, the results are more contrasted and sometimes approach those of the control and other times closer to the transparent modality. Regarding the analytical results, similar conclusions could be drawn with respect to the sensory tests. In fact, the transparent modality is the variant which has an absorbance of the UV-C solution that is twice as high as the other modalities after the 7-day treatment in the chamber. In view of the sensory and analytical results obtained in this study, the choice of the color of the bottles turns out to be an essential element in influencing the intrinsic and extrinsic characteristics of a wine. In order to preserve the qualities of the wine over the medium and long term, dark and opaque tints should be favored. Conversely, a transparent glass could be recommended in the case of rapid consumption of the wine after bottling.

Rhineland-Palatinate is Germany’s largest wine growing region. The recently launched collaborative project in the frame of the ‘Carl-Zeiss-Stiftungs-Kooperationsfonds für Nachhaltigkeitsforschung’ focusses on the risk-benefit assessment of the use of grape pomace (GP) from the region ‘Pfalz’ in Rhineland-Palatinate as a natural fertilizer

A large population of vines of the Mandón minority red variety (synonymous with Garró) has been located in old vineyards of the D.O. Arribes (Zamora and Salamanca) to conserve and recover this minority variety. The wines made with this variety are characterized by their good structure and color, interesting harmony, an excellently low pH, with high acidity, as well as complex aromas of blue fruits and a marked and expressive minerality.

In the Cognac region in France, Ugni blanc is the most planted grape variety (98% of the 80 500 ha). This vine region is in expansion due to the success of the associated well-known brandy and the need of high grape yield to guarrantee the production of base wine for distillation. About 2 to 3000 ha are newly planted each year and rootstocks are one powerfull tool for vineyard adaptation to soil or climate change. As rootstocks ensure water and mineral nutrient supplies to the scion, it is important to better understand their effect on berry compostionnal parameters such as sugars and nitrogen compounds, which are the main precursors for fermentary aroma metabolites, the latter being quality markers for Cognac after distillation.