Is it faulty?

Monday, 10 April, 2023
Jeremy Maarschalk
This wine tastes off! Despite the best efforts of winemakers, wine can sometimes develop faults that detract from its flavour, aroma, and appearance.

Developing an acute palate able to discern minor changes in wines is developed over time, it takes years off tasting, learning and devotion to the wine-tasting craft, but no matter your level of wine tasting experience, you can tell when a wine tastes ‘funny’, ‘off’ or ‘faulty’.

Wine is a complex and delicate luxury that requires precise conditions during production and storage to maintain its quality. Winemakers work tirelessly to ensure that their cellars are clean, neat and tidy to ensure that no faults creep into the wine from poor cellar practices.

In this article, you will find a couple of common faults in wine, its cause and how to discern the fault in the wine.

Oxidation

Oxidation occurs when wine is exposed to too much oxygen, either during production or storage. This can cause the wine to develop a brownish colour and a flat, stale taste. Some oxidation is necessary for the ageing process, but too much can ruin a wine's flavour. Oxidized wine may also have a nutty or sherry-like aroma.

Did you know: There is a winemaking style called oxidative winemaking where the wine is exposed to oxygen to help develop flavours in the wine.

Cork taint

Cork Taint can be detected via the aroma of the wine.

Cork taint is caused by a chemical compound called TCA, which can develop in the cork oak tree. When wine is sealed with a cork closure that has been affected by TCA, it can develop a musty, damp aroma that is often described as wet cardboard or dam water. Corked wines not only have this off aroma but they also display muted flavours and a flat finish.

Volatile acidity

Volatility in wine refers to the presence of acetic acid, which is created when bacteria consume the wine's sugars during fermentation. In small amounts, volatile acidity can contribute to a wine's aroma and flavour, but too much can make the wine smell and taste like vinegar.

In wine grapes, there are three main acid compounds namely tartaric, malic, and citric acids, along with these three acid compounds we find that acetic, lactic, and succinic acids become more prevalent in finished wines.

Tartaric acid is considered the most important acid in wine as it helps to maintain chemical stability.

Malic acid is the acid responsible for the green, or unripe flavours in a wine.

Citric acid is the acid responsible for the citrus notes in wine, the lime, lemon or orange flavours.

Lactic acid is associated with the milky or creamy characteristics in wines.

Reduction

Reduction occurs when wine is not exposed to enough oxygen during production or storage. This can cause the wine to develop a sulfur-like aroma, which is often described as smelling like burnt rubber or rotten eggs. The wine may also taste flat or lack complexity.

Heat damage

Wine that has been exposed to high temperatures, either during shipping or storage, can develop heat damage. This can cause the wine to taste cooked or stewed, with flavours that are jammy or raisiny. Heat damage can also cause the wine to lose its acidity, making it taste flabby and unbalanced.

Brettanomyces

Brettanomyces is a type of yeast that can develop in wine, particularly in red wines that have been aged in oak barrels. This yeast can create a range of aromas and flavours, from smoky and spicy to horse blanket, a characteristic we consider as a fault. In small amounts, these flavours can contribute to a wine's complexity, but too much Brettanomyces can overwhelm the wine's natural flavours and aromas.

Faults in wine can be caused by a range of factors, from storage conditions to the fermentation process. By understanding the most common faults, wine lovers can identify and avoid wines that present one of these faults. It's important to note that not all faults are the result of poor winemaking, and some may be a matter of personal preference.