CHEMISTRY OF WINE AROMAS

The perception of the taste and aroma of wine is the result of many interactions between a large number of chemical compounds and sensory receptors. Compounds interact, combine and exhibit synergistic and antagonistic interactions. The chemical profile of wine is determined on the basis of grapes, fermentation microflora (in particular, Saccharomyces cerevisiae yeast), secondary microbial fermentation, as well as aging and storage conditions. The composition of grapes depends on the varietal and clonal genotype of the vine, as well as on the interaction of the genotype and its phenotype with many environmental factors, which, in wine terms, are usually grouped under the concept of "terroir" (macro-, meso- and microclimate, soil), topography). The microflora and yeasts responsible for fermentation contribute to the aroma of wine through several mechanisms: first, by using the components of the grape juice and biotransforming them into components that affect the aroma or taste, and second, by producing enzymes that convert neutral compounds of the grape into aromatic, and finally, by de novo synthesis of many primary (e.g., ethanol, glycerol, acetic acid, and acetaldehyde) and secondary metabolites (e.g., esters, higher alcohols, fatty acids). This article aims to present an overview of wine aroma and flavor formation, including varietal precursor molecules present in grapes and chemical compounds produced during alcoholic fermentation by yeasts, including compounds directly related to the production of ethanol or secondary metabolites