Oxygen is a key player in oenology, since its effects can be a blessing, benefiting wine quality, or a curse causing irreversible damage.
Studying wine metabolome through multiple targeted methods is complicated and limitative; since grapes, yeasts, bacteria, oxygen, enological techniques and wine aging collaborate to deliver one of the richest metabolomic fingerprint.
The perception of wine quality is determined by the assessment of multiple sensory stimuli, including aroma, taste, mouthfeel and visual aspects. With so many different parameters contributing to the overall perception of wine quality, it is important to consider the contribution of all metabolites in a wine when attempting to relate composition to quality.
Much research has sought to define the complex contribution of terroir (varieties x site x cultural practices) on wine composition. This investigation applied recent advances in chemometrics to determine relative contributions of vine growth, berry maturity and site mesoclimate to wine composition and sensory profiles of Shiraz and Cabernet Sauvignon for two vintages.
Many compounds of interest in wine are difficult to analyze since they are present in very small quantities or they are unstable. The need for reliable data led scientists to develop complex method in order to overcome the analytical difficulties and provide accurate quantitative data for grape or wine characterization.
Oenological tannins are classified as hydrolysable and condensed tannins. Their use in winemaking is only authorized, to facilitate wine fining. Nevertheless, tannins could also be used to prevent laccase effects.
Wine aroma is shaped by the wine’s chemical compositions, in which both grape constituents and microbes play crucial roles. Although wine quality is influenced by the microbial communities, less is known about their population interactions.
Many volatile compounds of different chemical/biochemical origin contribute to wine aroma. Certain key ‘varietal’ aroma compounds such as methoxypyrazines are formed in the grape and appear to be only scarcely influenced by fermentation.
The light exposure of white wine is responsible for several reactions leading to changes on colour, flavours and, consequently, affecting the sensory profile.
Hydrogen sulfide (H2S) has a significant impact on wine aroma attributes and wine quality when present at concentrations above its aroma threshold of 1.1 to 1.6 μg/L.
Glutathione-rich inactivated dry yeasts (GSH-IDY) are claimed to accumulate intracellularly and then release glutathione in the must.
Oxygen consumed by wine is used to oxidize sulfur dioxide and ethanol to form acetaldehyde wine oxygen consumption rate (OCR) was negatively correlated with the initial acetaldehyde level.
Cognac spirit aromas result from the presence of a wide variety of volatile odorous compounds associated with the modalities of distilled spirit elaboration and during aging. Indeed, these odorous compounds play an essential role in the finesse and complexity of the aged Cognac.
Grapes composition is a factor well known to affect wines composition and sensory expression. The goal of this study was to evaluate how grapes composition modifications linked to maturity level could affect wines aromatic expression and esters composition.
There are yet many gaps in our knowledge about the aroma potential of winemaking grapes and its measurement. Trying to bring some light into this question, a new general strategy based on the accelerated hydrolysis of reconstituted phenolic and aromatic fractions (PAFs) extracted from grapes has been developed
Bottle ageing is considered essential for most premium red wine production. An important aim of bottle ageing of wine is to achieve a balance between the oxidative and reductive development. This is typically evaluated by the accumulation of aldehyde compounds (causing oxidative off-flavour) and sulfur-containing compounds (causing reductive off-flavour) in the wine [1]
Rosé wine consumption is rapidly increasing with its market share in France that has grown from 11 % to 32 % in less than 20 years. A recent trend is also to produce rosé wines with lighter colors. Varieties, terroir and technology certainly have an influence on rosé wine colors.
Polyphenols, namely anthocyanins and flavanols, are key compounds for wine color definition and taste perception (astringency and bitterness). During winemaking, several processes could influence the polyphenol composition and, therefore, the organoleptic parameters of wine.