वाइन दोष

Contamination by Brettanomyces/Dekkera yeast species, which thrive on trace sugars in wine. Brett produces 4-ethylphenol (band-aid, barnyard) and 4-ethylguaiacol (smoky, spicy). Can colonize barrels, making …

2,4,6-trichloroanisole (TCA) is produced when natural cork compounds interact with chlorine-based sanitizers and airborne fungi. TCA can contaminate not just corks but entire cellars, barrels, …

Produced by acetic acid bacteria and some wild yeasts. Ethyl acetate is naturally present in all wines at low levels (50-80 mg/L) where it contributes …

Lactic acid bacteria metabolize sorbic acid (a preservative) into 2-ethoxyhexa-3,5-diene, which has an intense geranium leaf/crushed geranium aroma. Only occurs when sorbic acid (potassium sorbate) …

Exposure to temperatures above 30°C during shipping, storage, or in retail environments. Wine literally 'cooks,' accelerating chemical reactions. Common when wine is left in hot …

Ultraviolet and visible light catalyze riboflavin (vitamin B2) and amino acids in wine to form dimethyl disulfide and methanethiol. White wines in clear glass are …

Lactic acid bacteria (Lactobacillus, Pediococcus) and some Brettanomyces strains produce compounds (2-acetyl-1-pyrroline, 2-ethyltetrahydropyridine) that cause a mouse-cage-like aftertaste. Particularly associated with low-SO2 and natural wines.

Excessive oxygen exposure during winemaking or storage. Caused by poor topping of barrels, faulty seals, or storing opened wine too long. Acetaldehyde is the key …

Controversial condition primarily affecting white Burgundy from 1996-2005 vintages (and other regions). Wines age decades faster than expected. Suspected causes: poor cork quality, insufficient SO2 …

Insufficient oxygen during fermentation or aging, leading to formation of hydrogen sulfide (H2S) and mercaptans (thiols). Common in wines fermented in sealed stainless steel tanks …

Residual yeast and sugar in an improperly stabilized wine reactivate after bottling, producing CO2. Common in wines with residual sugar that were not sterile-filtered. Can …

Grapevine exposure to wildfire smoke during the growing season (véraison through harvest is the most vulnerable period). Volatile phenols (guaiacol, 4-methylguaiacol) from smoke are absorbed …

Over-addition of SO2 (sulfites) during winemaking. SO2 is a necessary preservative and antioxidant, but excessive amounts at bottling create perceivable off-aromas. Legal limits vary: 160 …

Potassium bitartrate crystallization — a natural, harmless precipitation of tartaric acid salts when wine is chilled below the temperature at which it was stored. More …

Acetic acid bacteria (Acetobacter) convert ethanol to acetic acid (vinegar) and ethyl acetate (nail polish remover) in the presence of oxygen. Can also be produced …