Implementation of hyperspectral image analysis for evaluating table grape quality on bunch and berry level

A misconception lingers in the minds of some wine consumers that Champagne wines don’t age. It’s largely a myth, certainly as far as the best cuvees are concerned. Actually, during the so-called autolysis period of time (in the closed bottle, after the “prise de mousse”), complex chemical reactions take place when the wine remains in contact with the dead yeast cells, which progressively bring complex and very much sought-after aromas to champagne. Nevertheless, despite their remarkable impermeability to liquid and air, caps or natural cork stoppers used to cork the bottles are not 100% hermetic with regard to gas transfers. Gas species therefore very slowly diffuse through the cap or cork stopper, along their respective inverse partial pressure. After the “prise de mousse”, because the partial pressure of CO2 in the bottleneck reaches up to 6 bars (at 12 °C), gaseous CO2 progressively diffuse from the bottle to the ambient air
(where the partial pressure of gaseous CO2 is only of order of 0,0004 bar).

Scientific information on grapevine response to predicted levels of climate parameters is scarce and not sufficient to properly position the Wine Industry for the future. It is critical that the combined effects of increased temperature and CO2 on grapevines should be examined, without omitting the important link to soil water conditions. The purpose of this study is to quantify the effects of envisioned changes in climatic parameters on the functioning and growth of young grafted grapevines under controlled conditions, simulating expected future climate changes. Scientific knowledge of precisely how the newly-planted grapevine will react morphologically, anatomically and physiologically (at leaf, root and whole plant level) to the expected changes in important climatic parameters will enable producers to make better-informed decisions regarding terroir, cultivar and rootstock choices as well as the adaptation of current cultivation practices.

The relationship between grape production and leaf surface is a highly debated aspect in terms of the impact it may have on the composition and quality of grapes, especially in areas that focus their cultivation on high-quality wine. In many occasions, the limitation of the unitary production level in these areas is claimed to be the main factor for achieving high quality levels in the wine, forgetting the importance of the source-sink relationship and other environmental factors and management of the canopy. Taking this consideration into account, this work seeks to know the response of the vine as a whole, and the individual shoot as well, to the application of various alternatives of leaves and clusters removal, carried out in the phase immediately before veraison, in cv. Verdejo, in Spain.

The recent expansion of arid areas due to climate change is putting grapevine and the other traditional productions at risk in all Mediterranean countries with a limited availability of fundamental resources such as water. It is possible to improve the resilience of vineyards by developing sustainable agricultural practices based on biological and natural resources such as endophytic microorganisms that colonize inner plant tissues, and which can potentially increase the tolerance to abiotic stresses. A selection of grapevine endophytes was conducted from 2021 to 2023 as part of the PRIMA project PROSIT.

In red wines the post-MLF SO2 addition is an essential event. It is also the case for the “mutage” during the elaboration of the “liquoreux”. At these moments SO2 plays an antimicrobial action and an antioxidant effect. But at current pH of wines, ensuring a powerful molecular SO2 has become very difficult. Recent work on Brettanomyces strains have also shown that some strains are resistant up to 1.2 mg / L of molecular SO2. It’s also the case of the some Saccharomuces or Zygosaccharomyces strains suitable to re-ferment “liquoreux” wines after the “mutage”.