Despite the facts that the average quality of win has been increasing over the last two decades and the large majority of current wines rarely present serious flaws, it is always useful and convenient to know how to identify the most common flaws in the world of wine.


It’s the most common abbreviation of the word “trichloroanisole”, that designates a compound with a particularly repulsive smell like a mixture of mold, wet card and dust. The most common cause for its manifestation in the wine rests on contaminated natural corks. TCA can attack any type of cork stoppers, including the most expensive, and it is regarded as the most common flaw found in wine bottles.

Sulphur dioxide

Sulfur is one of the oldest natural antiseptics used virtually in all the wines since before the immemorial times of the wine prehistory. It protects wine from the oxygen and its use is essential in all types of wine. When present in high doses, however, it can be identified as the acre puff of a just burnt match. The aromas can be dispelled with the process of decantation and with a strong aeration.


Oxidation is a generic term and hard to characterize that describes wine flaws that result from too much oxygen absorption. Oxidation is a typical flaw of the lighter and more delicate wines, causing a tasteless and tired flavour in white wines,a sour or sweet flavour in red wines.


Contamination that originates aromas of the fur of a mouse, a strong animal smell, stable or saddle aroma. The flaw, which in a minimum proportion can be considered as a virtue, is due to a bacterial contamination that lodges in the cellar and it has proven to be quite difficult to remove.

Hydrogen sulphide

Often simply identified as sulphide, it produces very unpleasant smells similar to the odour of rotten eggs or burnt rubber. If it isn’t treated in time in the cellar, the sulphide may turn into mercaptans, displaying disgusting sewer, onion and garlic aromas.

Acetic Acid

The wine has surpassed the oxidation phase a long time ago and it started displaying vinegar aromas.

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