Climat et sol: critères d’évaluation et effets sur le comportement de la vigne

Secondary (or specialised) metabolites such as terpenes and phenolic compounds are produced by plants for various roles which include defence against pathogens and herbivores, protection against abiotic stress, and plant signalling. Additionally, these metabolites influence grapevine quality traits such as colour, aroma, taste, and nutritional value. However, the biosynthesis of these metabolites is often complex and controlled by multiple genes which in grapevine are predominantly uncharacterised.

Bases on oxoluminescence, we have developed an innovative device for measuring dissolved oxygen in wines in barrels without opening the bung. This system is directly inserted into the wood during the barrel elaboration and can be positioned at different locations of the barrel (the head, the hull …). During two successive vintages we have used this device notably to follow the oxygen dissolved of whites wines elaborated in barrels. This allowed us initially to monitor the oxygen levels of the harvest to bottling the whole elaboration process in barrels of white wines without using techniques of measurement suitable to modify the real values in wines (opening the bung to plunge an oximeter).

Wine flavour is the integration of distinct physiologically defined sensory systems that combine taste, aroma and trigeminal sensations, and it is a key determinant factor for the acceptance of wine by consumers. Volatile compounds, are important contributors to wine flavour, specially to aroma. These small and low-boiling point compounds are easily released into the air allowing to enter and move within the nasal or oral cavities where they can bind the olfactory receptors. Additionally, wine also contains aroma precursors, which are non-volatile compounds, but that can be broken down releasing volatile odorants. During wine tasting, all these chemicals (volatiles and non-volatiles) can be submitted to the action of salivary enzymes.

Egri Bikavér (Bull’s Blood) is one of the most remarkable Hungarian red wines on inland and foreign markets as well. From the end of the 70’s the quality of Egri Bikavér was decreasing continually due to mass production. The concept of production of quality wines became general in the mid 90’s again and it resulted in a new Origin Control System, for the first time that of Egri Bikavér in Hungary.

Climate change has a strong impact on the earlier onset of important phenological stages and plant development in viticulture.