Changes in flavonol profile are a reliable indicator to assess the exposure of red grape berries to solar radiation and canopy architecture

Pinot noir has its historical roots in Burgundy and is generally considered as an endemic vine variety which means that its adaptation is very specific to this environment

Fermentation derived sulfidic off-odors due to hydrogen sulfide (H2S) and low molecular weight thiols are commonly encountered in wine production and removed by Cu(II) fining. However, the mechanism underlying Cu(II) fining remains poorly understood, and generally results in increased Cu concentration that lead to deleterious reactions in finished wine. The present study describes a mechanistic investigation of the iron and copper mediated reaction of H2S, cysteine, 3-sulfanylhexan-1-ol, and 6-sulfanylhexan-1-ol with oxygen. The concentrations of H2S, thiols, oxygen, and acetaldehyde were monitored over time. It was found that Cu(II) was rapidly reduced by both H2S and thiols to Cu(I).

Originaire du bassin lémanique, le chasselas est l’emblème de la viticulture suisse. Pour autant, les surfaces de chasselas n’ont cessé de diminuer, passant de 6’585 hectares en 1986 à près de 3’600 aujourd’hui, reflet d’une baisse de consommation. Une récente étude a cherché à comprendre les raisons de ce désintérêt. Réalisée dans

Wine research in the past years has mainly been focused on laboratory scale due to the possibility of controlling winemaking variables. Conversely, studies on wine quality in relation to the winemaking variables at the winery scale may be able to better account for the actual challenges encountered during wine production. Winemaking problems are recently arising from progressive changes in environmental conditions in relation to the terroir. It is important to realize that each wine region may have specific winemaking protocols and that winemakers often base their decisions on subjective, emotional, and empirical opinions. Due to all the above-mentioned issues, taking the correct decision in winemaking to achieve the desired goals may become even more challenging.

The disruptive effect exerted by high-power ultrasound (US) on plant cell walls, natural barriers to the diffusion of compounds of interest during the maceration of red wines, is established as the reason behind the chromatic improvement that its treatment causes. However, sometimes this improvement is not observed, especially with short maceration times. The presence of a high quantity of suspended cell wall material, which formation is favored by the sonication, could be the cause of this lack of positive results since this cell wall material has a high affinity for phenolic compounds.