Guidelines to optimise the sensory detection of 2,4,6-trichloroanisole in neutral spirit and whisky

Abstract

Why was the work done: Guidelines are required to optimise the sensory detection of musty/stale taints in alcoholic spirits caused by 2,4,6-trichloroanisole. Early detection of the taint is necessary as the low sensory threshold can result in significant quality issues and masking the musty/stale off-note through blending is difficult. How was the work done: The standard industry practice for ‘nosing’ is to dilute samples of spirit to 20% ABV to prevent sensory fatigue.  It is not known if 20% ABV is the optimal concentration for detecting 2,4,6-trichloroanisole. In this study, the effects of ethanol concentration on the detection of the taint were evaluated using a sensory panel and gas chromatography-mass spectroscopy. The efficacy of nosing versus tasting to detect 2,4,6-trichloroanisole was investigated at different dilutions of distilled spirits. Further, the stability of this off-note at 20% ABV was determined to assess if the taint could be detected by nosing over a working day. Finally, the serving temperature of the sample was assessed in the sensory perception of the taint. What are the main findings: The recommendations to optimise the sensory detection of 2,4,6-trichloroanisole in spirit samples are (i) nose samples at 20% ABV, (ii) as soon as possible after dilution conduct sensory tests and (iii) chill the sample. Why is the work important: The limits of detection for conventional solid phase microextraction with gas chromatography-mass spectroscopy are typically above the threshold of human perception. Therefore, the industry needs to maximise the detection by sensory panellists of contaminated whisky samples to ensure the product does not go to market so as to avoid any reputational damage.