Nitrogen metabolism in Kluyveromyces marxianus and Saccharomyces cerevisiae: towards a better understanding of fermentation aroma production

Climate change presents a significant challenge for actual viticulture. In this context, recovering minority grape varieties can be a crucial strategy to ensure resilience, particularly those capable of maintaining quality and aromatic complexity under water stress.

Several winemaking operations, such as filtration, pumping, and racking, are known to potentially facilitate the incorporation of atmospheric O2 into the wine. Control of grape must oxidation is one key aspect in the management of white wine aroma expression, color stability and shelf-life extension. On the one hand, controlled must oxidation may help to remove highly reactive phenolic compounds, which otherwise could contribute to premature oxidation. And on the other hand, in certain cases of extreme protection of the must from O2 (e.g. pressing under inert atmosphere), it can help to preserve varietal aromas and natural must antioxidants.

Light is responsible for adverse reactions in wine including the formation of unpleasant flavors, loss of vitamins or photodegradation of anthocyanins. Among them, the riboflavin degradation leads to the formation of undesirable volatile compounds, known as light-struck taste. These photo-chemical reactions could be avoided by simply using opaque packaging. However, most rosé wines are kept in transparent bottles due to different commercial reasons. Some agri-food waste extracts have been studied for their photoprotective action which turn to be highly correlated with phenolic content [1].

Vineyards are home to a wide diversity of microorganisms that interact with plants and with each other.

Various molecular compounds are responsible for the complex mixture of fragrances that give wine its aroma. In particular, the ‘cooked fruit’ aroma found in red wines from hot and/or dry vintages or from the vinification of late harvested grapes has been intensively investigated in recent years. Lactones and especially γ-nonalactone were found to be responsible for the ‘cooked fruit’