corktaint

Cork taint is a wine fault associated with natural cork closures, caused primarily by compounds such as 2,4,6-trichloroanisole (TCA) and related chlorinated anisoles. Wines affected by cork taint typically exhibit a musty, damp, moldy, or cardboard-like aroma and flavor that can overpower fruit and other characteristic notes. The defect is linked to the cork material but can occasionally arise from other packaging components contaminated with similar compounds.

Causes and chemistry

Cork taint arises when precursors present in cork bark or processing reagents interact with fungi in the presence of chlorine-based sanitizers, forming chlorinated anisoles such as TCA. Natural cork is the main source of the problem, though trace contamination can occur with other materials handled in the bottling line. TCA and related compounds are extremely potent, so very low concentrations can be detectable in wine, even if only a small portion of the bottle is tainted.

Prevalence and impact

Cork taint affects a minority of wines sealed with natural cork, with estimates varying by region, supplier, and quality controls. It is a fault in the closure rather than an intrinsic flaw of the wine itself, and its impact ranges from barely perceptible to clearly noticeable in the bottle.

Detection and remediation

There is no remedy to restore tainted wine; once cork taint is present, decanting or aeration is unlikely to remove it. If detected, producers may offer replacements or refunds, and affected wines are typically identified as corked rather than flawed by the winemaking process.

Mitigation and alternatives

To reduce cork taint risk, many producers use alternative closures (screw caps or synthetic corks) or source higher-quality, TCA-tested corks. Ongoing quality control and supplier testing aim to minimize taint in bottled wines.