TCA has a sensory detection threshold of 1 ng/L in wine as a mouldy / musty off aroma. A new accurate method has been developed for the quantitative analysis of 2,4,6-trichloroanisole (TCA) and other chloroanisoles in wine. The method uses capillary gas chromatography coupled with EI Mass Spectrometry, using selective ion monitoring and a synthetic polydeuterated form of TCA, d5-TCA as an internal standard.
The detection limit for all chloroanisoles was 0.5 ng/L in red wine and the calibration curve for TCA showed reasonable linearity throughout the range of 0.5 to 200 ng/L with a correlation coefficient of 0.999. The calibration curves for the other chloroanisoles showed similar correlation coefficients.
The analytical method was applied to wines assessed as affected by cork-taint by participants in the 1995 Advanced Wine Assessment Course, held in conjunction with staff of the Australian Wine Research Institute. 398 bottles of red, white, sparkling and fortified wine were presented throughout the course.
Of the 398 bottles of red, white, sparkling and fortified wine presented 18 (4.5%) were assessed as being affected by cork-taint. 8% of the dry white wines were so affected.
TCA was present in all wines assessed as being affected by cork-taint.