Le zonage viticole: instrument pour la récuperation d’un ancien cépage des collines de Conegliano (Verdiso – V. vinifera)

Climate change leads to even more hostile and stressful for the wine microorganism conditions and consequently issues with fermentation rate progression and off-character formation are frequently observed. The objective of the current research was to classify a great collection of yeast isolates from Greek wines based on their technological properties with oenological interest. Towards this direction, fourteen spontaneously fermented wines from different regions of Greece were collected for further yeast typing. The yeast isolates were subjected in molecular analyses and identification at species level.

Climate change and environmental degradation are existential threats to europe and the world. One of the most important objectives is to reduce by 2030 the use and the risk of chemical pesticides and fertilisers, reducing nutrient losses and increasing organic farming. Grapevine (vitis spp.) is one of the major and most economically important fruit crops worldwide. It is characterised by high levels of genetic diversity, as result of natural genetic mutations, which are common in grapevines and further assisted by ongoing vegetative propagation.

Berry Shrivel (BS, Traubenwelke) is a sugar accumulation disorder of grapevine of unknown causes, having a great negative impact on grape quality and incalculable risks for yield losses, and for which no reliable curative practices are available.

The mapping of spatial variability in vineyards offers the potential to implement zonal management strategies with the aim to optimize economic benefits and increase sustainability by managing natural resources, such as water used for irrigation, more optimally. This study characterized the (natural) variability in plant water status in a commercial Cabernet Sauvignon block, using remote sensing techniques, and identified the impact of this variability on the yield, and juice and wine composition. From the field data collected over two growing seasons, we demonstrated that remote sensing techniques are a practical and powerful tool for mapping spatial variability within vineyard blocks.

Several classes of flavonoids, such as anthocyanins, flavonols, flavanols and flavones, undergo a slow H/D exchange on aromatic ring A, leading to full deuteration at positions C(6) and C(8). Within the flavanol class, H-C(6) and H-C(8) of catechin and epicatechin are slowly exchanged in D2O to the corresponding deuterated analogues; even quercetin, a relevant flavonol representative, shows the same behaviour in a D2O/DMSOd6 1:1 solution. Detailed kinetic measurements of these H/D scrambling processes are here reported by exploiting the time-dependent changes of their peak areas in the 1H-NMR spectra taken at different temperatures. A unifying reaction mechanism is also proposed based on our detailed kinetic observations, even taking into account pH and solvent effects. Molecular modelling and QM calculations were also carried out to shed more light on several molecular details of the proposed mechanism.