Wine Education Wednesdays: Cork Taint
This week we are learning what cork taint is and what it actually means to have a “corked wine” – and no, it is not those small bits of cork that you occasionally find floating in your glass.
Corked wines display aromas of wet cardboard, damp, and mould, and generally a complete lack of fruit. The aromas are caused by a chemical present in the cork itself, rather than it being a fault with the wine – a chemical known as TCA or Tri-Chloro-Anisole.
So, what causes TCA?
Corks are made from thick sections of bark grown on cork oaks, mostly in Portuguese forests, but you also find them in Spain, Sardinia, and Sicily. TCA is not naturally found in oak trees, but when certain moulds or fungi come into contact with chlorophenols – which are commonly found in pesticides – the compound can be formed.
The overuse of pesticides, insecticides, and fungicides in the late 20th century (when less was known about their impact on the environment) is thought to be largely to blame for the presence of TCA in cork. If a tainted cork ends up stopping your wine – all those mouldy aromas are imparted into the liquid and the wine is devastatingly ruined.
Whilst humans generally are very good at detecting cork taint, the signs can be less obvious to some – so importantly, if you do drink a corked wine, you can feel safe in the knowledge that it’s not going to cause you any harm. It just won’t taste very good.
Huge efforts and considerable investments have been made to tackle the cork taint problem – and of course many wine producers simply prefer to use closures such as screw caps or synthetic corks to side-step the problem entirely. But there is something rather satisfying about pulling a cork isn’t there…
