Conservation: the best valorisation strategy for wine growing areas

In the past decade, there has been an increasing amount of work dedicated to understanding micro-oxygenation in wine.

Grapevine leafroll associated virus (GLRaV) infections deteriorate vine physiological performance and cause high losses of yield and fruit quality

IFV, INRAe and the national network “Partenaires de la Sélection Vigne” representing 37 organizations from the different wine regions, have been working increasingly closely over the last 2 decades towards the preservation of the French varietal patrimony. There are approximately 600 patrimonial varieties according to INRAe and SupAgro Montpellier experts, including ancient cultivars (400) and intravarietal crossbreeds obtained since the 19th century. In the context of a drastic reduction in such varieties from the mid 1980’s in favor of mainstream varieties, it was essential to carry out an inventory of old vines and vineyards. INRAe Vassal collection plays a key role here as it holds the largest diversity available, along with a rich bibliography and herbariums, offering us the opportunity to document and double check the identity of a cultivar, consolidating the expertise of ampelographers. The work is carried out in several stages, from verifying the existence of a variety in a small region, through to rehabilitation. During this session, the authors present the process that leads to the official registration of a variety. After this, IFV selection center takes over to initiate the process of selection and propagation. A specific focus within regions such as the Alps, Champagne and the South-West will provide details of the full procedure. Bia, Bouysselet, Chardonnay rose, Mecle and the aptly named Tardif, are some of the cultivars that have followed this procedure. Furthermore, a recent regulation established by INAO on “varieties of interest for adaptation purposes” might boost uptake by growers. Since 2006, 36 historical cultivars have been registered. Most of these have been neglected in the past due to late maturity, lack of sugar and high titratable acidity at harvest time. Such characteristics are today considered as positive qualities, not only in mitigation of the effects of climate change, but also as an opportunity for restoring diversity…

The tartaric stabilization of wines before bottling to avoid the precipitation of tartaric acid salts is an important and common step during wine production. The presence of precipitated salt crystals in bottle wines is detrimental for their quality and even a legal issue in some countries. Cold stabilization is the most common stabilization treatment. Although it has been shown to be effective, it has some significant disadvantages, mainly regarding losses of color and aromas and its high cost. Therefore, other products and methodologies are being introduced in the wineries for the replacement of this process. Some of these new techniques involve the reduction of the ions causing the insolubilization of tartaric acid while other are based in the formation of protective colloids or the inhibition of the crystallization of salts. In this study, white, rosé and red wines have been treated with carboxymethylcellulose, potassium polyaspartate and an ion exchange resin. The tartaric stability of the wines, together with the oenological, chromatic and sensory characteristics were studied after the wines had been stored during one year in the bottle. The results indicate that the use of carboxymethyl cellulose and potassium polyaspartate maintained the best the sensory and chromatic characteristics and the wine stability of the wines in comparison with an untreated control wine.

The complexity of the wine matrix makes the monitoring of the winemaking process crucial. Fourier Transform Infrared Spectroscopy (FTIR) along with chemometrics is considered an effective analytical tool combining good accuracy, robustness, high sample throughput, and “green character”. Portable and non-portable FTIR devices are already used by the wine industry for routine analysis. However, the analytical calibrations need to be enriched, and some others are still waiting to be thoroughly developed.