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.