When it comes to wine, our palate and sense of smell expect a range of aromas: fruity, floral, spicy or roasted. But sometimes, a glass can surprise us with hints that are out of the ordinary, capable of surprising even the most experienced tasters. Where do these unusual aromas come from? Let's find out together!
Wine that tastes like truffles. One of the most surprising aromas in wine is the hint of truffle. This particular smell often develops in aged red wines, such as Nebbiolo or Pinot Noir, due to the presence of sulfur compounds that develop over time during the aging process. Truffle aroma is often linked to long aging and specific terroirs rich in calcareous marls, which favor this olfactory characteristic.
It is due to a molecule called DMS (dimethyl sulfide). Perceived in high concentrations, DMS has a very unpleasant odor and is often considered to cause a defect in Wine with notes of cooked corn, tomato, and asparagus. However, in lower concentrations, it can enrich the complexity of a Wine's bouquet by adding notes of truffle. As red Wine ages in the bottle, the concentration of DMS increases to peak after 10-15 years. It can be present in many robust Red Wines but is considered a characteristic aroma of the great Red Wines aged between 10 and 20 years in the Bordeaux region.
Wine with hints of hydrocarbons? Welcome to the world of Riesling! If you have ever smelled an aged Riesling, you may have noticed an aroma reminiscent of gasoline or kerosene. This is due to the presence of the chemical compound TDN (1,1,6-trimethyl-1,2-dihydronaphthalene), which develops as the wine ages and as the grapes ripen under conditions of strong sunlight and slate-rich soils (in fact, this aroma can be very noticeable even in some young Rieslings). The aroma may seem unusual, but it is highly valued by Riesling connoisseurs; it adds complexity to the wine's bouquet, but it must be subtle and not overpower the other aromas.
A wine that smells like smoked bacon. Some Syrahs and wines produced in the Rhone Valley may have an intense smoky, almost bacon or bacon-like aroma. This is due to the presence of phenolic compounds such as guaiacol and 4-methyl-guaiacol, resulting from fermentation processes and the possible use of toasted oak barrels. In addition, volcanic terroir can intensify these scents, giving the wine an even more distinctive character.
The marine note in wine: the smell of oysters and saltiness. Some white wines, such as Muscadet or certain Vermentinos grown near the sea, have an unmistakable hint of saltiness and iodine. This effect is often attributed to the influence of the marine climate and soils rich in marine fossils, which help give the wine a distinctive and refreshing character.
The vegetal side is a wine that smells like green peppers. Cabernet Sauvignons, Carmenère, and Sauvignon Blancs often have herbaceous notes of green bell pepper or tomato leaf. This aroma is due to the presence of pyrazines, aromatic compounds naturally present in grapes. When dosed well, this aroma adds freshness and complexity, but if too intense, it can be unpleasant.
Wine with stable and leather odor. Some red wines, particularly those made from Syrah and Mourvèdre grapes, may develop aromas reminiscent of barn, leather, or horse sweat. These hints are often attributed to the presence of the yeast Brettanomyces, which can contribute to the wine's complexity if present in moderate amounts but become a fault if too dominant.
Noble mold or defect? Some sweet wines, such as Sauternes or Tokaji, develop notes of noble rot through the action of Botrytis cinerea, a beneficial mold that concentrates the sugars and aromas of the grape, giving hints of honey and apricot. However, unwanted mold, such as that which causes the smell of a damp cellar or wet cardboard, is a defect usually associated with the so-called “corky taste,” caused by TCA (trichloroanisole) contamination.
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Unusual aromas in wines can be both a pleasant surprise and a sign of faults. They should be subdued so as not to overpower the fruit and flower aromas typical of the varietal so that the wine does not lose identity. The key is to understand their origin and the context in which they develop. Terroir, fermentation, maturation and aging, and the presence of specific microorganisms can all profoundly influence a wine's flavor profile. The next time you encounter an unexpected aroma in a glass of wine, stop and analyze it: it could be an indication of terroir, the winemaking process, or a refined evolution over time. Enjoy your tasting!