The Effect of TCA (June 19, 2003)
Trichloranisole (TCA), the chemical compound that gives wine a "corky"
smell and taste, has a more aggressive and detrimental affect on a wine's flavour
than was previously thought.
The Australian Wine Research Institute has been conducting a three-year study
on the performance of wine stoppers. One of their findings is that the tiniest
amount of TCA – measured as low as one or two nanograms per litre –
can suppress the fruit flavours of a wine by as much as 50%.
This means that a wine does not necessarily need to smell "off" to
be considered "corked." The smell (similar to that of a musty basement)
might indicate that a wine is corked, but at light concentrations of TCA it
might not be detectable on the nose. The flavour profile of the wine, however,
may be seriously compromised.
Cork companies have argued that levels of 3 to 5 nanograms per litre of TCA
are not commercially important.