Santa Margherita

Even though these are present, in terms of weight, in quantities of only around 0.7–1.2 g/l, a wine’s aromatic content represents the element why we enjoy it to a greater or lesser degree: it is its most profound soul, and conveys much of the wine’s mysterious charm.
Volatile molecules can be categorized in a whole host of different ways: among the various classifications one of the most widely used is that connected with the moment in which they are formed. They can therefore be split up into:
- primary aromas;
- secondary aromas;
- tertiary aromas.

Primary aromas
In this group are included all the fragrant compounds that come directly from the grapes, where they are already present as sweet-smelling molecules or as precursors (potential aromas) that will subsequently evolve into real aromas.
We can find the following groups:
1.    monoterpenols: these are terpenic alcohols with the classic perfumes of flowers, Muscat grapes, citrus fruits and peaches that are characteristic of the aromatic varieties (Muscats, Gewürztraminer, Riesling, Brachetto, etc.);
2.    substances that are typical of American vine species: foxy sensations for Clinto, strawberries for Fragolino;
3.    metossipirazines: from these come the typical hints of green bell peppers and vegetal scents in general that one finds, for example in the Bordeaux varieties (Cabernet, Merlot), especially if obtained from grapes that are not particularly ripe;
4.    sulfurous thiol compounds: found in particular in Sauvignon Blanc with its typical scents of tomato leaves, elderflowers, passion fruit and grapefruit (but also to a lesser degree in other varieties, such as Müller Thurgau, Grillo, etc.);
5.    C13-norisoprenoids (with 13 carbon atoms): the smell of violets (beta-ionone), exotic fruits (beta-damascenone) or the legendary smell of hydrocarbons in aged Rieslings.

Secondary aromas
The members of this group are all the scented compounds formed during the operations of extracting and conditioning the must (pre-fermentation) and/or produced by the action of yeasts and bacteria during the alcoholic and malolactic fermentations.
Among those created pre-fermentation we can list:
1.    herbaceous and vegetal aromas (from hexanol and hexanal) as a consequence of enzymatic oxidation of the fatty acids (typical in Müller Thurgau or in other “mountain” varieties”);
2.    compounds deriving from carbonic maceration: for example, the scents reminiscent of strawberries or raspberries that one finds in Novello wines.

Among those deriving from the alcoholic fermentation there are:
1.    esters (ethyl acetate, isoamyl acetate, phenyl ethyl acetate, etc.): when these are pleasant smells, they tend to all have strong fruity aromas;
2.    volatile fatty acids (acetic acid, isovaleric acid)
3.    higher alcohols (propyl, isobutyric, isoamylic and phenyl ethyl alcohols): more than for their aromas, they are noticeable because of their tactile pungent effect on the nose;
4.    carbonyl compounds (acetaldehyde with its herbaceous/oxidized smell, benzaldehyde with its smell of bitter almonds or cherry stones, diacetale with its odor of solvent);
5.    volatile phenols (vinyl guaiacol and vinyl phenol, ethyl phenol and ethyl guaiacol) with smells that vary from spices to leather and even to the highly unpleasant odor of stables/horse sweat;
6.    sulfurous compounds (hydrogen sulphide, mercaptan) with bad odors of garlic and rotten eggs.

Among those from the malolactic fermentation there are:
1.    diacetyl, which gives a buttery or lactic smell;
2.    acetic acid, with a vinegary smell.


Tertiary aromas
These derive from compounds that form during the process of maturation and bottle-aging, as a result of enzymatic and physico-chemical activity that takes place in the wood or in the bottle.
We can distinguish those that occur in an oxidative environment by means of oxidation by alcohols on aldehydes (acetaldehyde) and ketones from those in a reductive environment (full barrels or other containers and bottles), as a consequence of phenomena of:
1.    esterification (between alcohol and acid);
2.    acetalization (between alcohol and aldehyde, with the formation of acetal);
3.    etherification (reaction between two alcohol molecules);
4.    hydrolysis (of ether oxides);
5.    polymerization (of the tannins);
6.    reduction.

To these we should certainly add those compounds that are yielded by wooden barrels such as:
- phenolic aldehydes, the principal one of which is vanillin;
- furanic aldehydes, such as furfural (toasted almonds);
- volatile phenols, from spicy to stable-like smells;
- phenyl ketones, with vanilla/woody notes;
- lactones, with the classic smell of coconut.