Effect of ozone application for low-input postharvest dehydration of wine grapes 

The characterization of chemical compounds related with quality of grape must and wine is relevant for the viticulture and enology fields. Analytical methods used for these analyses require expensive instrumentation as well as a long sample preparation processes and the use of chemical solvents. On the other hand, near-infrared (NIR) spectroscopy technique is a simple, fast and non-destructive method for the detection of chemical composition showing a fingerprint of the sample. It has been reported the potential of NIR spectroscopy to measure some enological parameters such as alcohol content, pH, organic acids, glycerol, reducing sugars and phenolic compounds.

L’AOC Priorat, située derrière les montagnes du pré littoral de Tarragone, se caractérise par un climat méditerranéen avec une tendance à la continentalité et très peu de précipitation pendant le cycle végétatif. Les sols sont secs, pauvres et caillouteux, formés par des schistes. Au cours des années 2000 et 2001, une étude de l’influence du terroir sur la typicité des vins du Priorat a été réalisée en prenant comme référence trois cépages cultivés dans différentes parceIles pour mesurer l’effet du terroir et du mésoclimat sur la qualité des vins:

The enzymatic browning of grape must is still a major problem in oenology today [1] being particularly serious when the grapes have been infected by grey rot [2]. Browning is an oxidation process that causes certain foods to turn brown, which often leads to them being rejected by consumers [3]. This is a particular problem in the case of wine, because grape must is very vulnerable to enzymatic browning [4].

Tangible variation of sensory characteristics is often perceived in wine aged in similar barrels. This variation is mostly explained by differences in the wood chemical composition, and in the production of the barrels. Despite these facts, the literature concerning barrel-to-barrel variation and its effect on wine sensory and chemical characteristics is very scarce [1]. In this study, the barrel-to-barrel variation in barrel-aged wines was examined in respect of the most important phenolic compounds of oenological interest and chromatic characteristics, considering both the effects of the (individual) barrel and cooperage. A red wine was aged in 49 new medium-toasted oak (Quercus petraea) barrels, from four cooperages, for 12 months

Smoke impact in wines is caused by a wide range of volatile phenols found in wildfire smoke. These compounds are absorbed and accumulate in berries, where they may also become glycosylated. Both volatile and glycosylated forms eventually end up in wine where they can cause off-flavors. The impact on wine aroma is mainly attributed to volatile phenols, while in-mouth hydrolysis of glycosylated forms may be responsible for long-lasting “ashy” aftertastes (1).