Trichloroanisol

NP NPEC OC OP OPEC PCB PCDBT PCDD PCDF PCP PFB RA TCA TCDD TCF TCMTB TOC VSC VOC Nonylphenol Nonylphenol ethoxycarboxylate Organo chlorine Octylphenol Octylphenol ethoxycarboxylate Polychloroinated biphenyls Polychlorinated dibenzothiophene Polychlorin ated dib enzo-p - dioxins Polychlorinated dibenzo-p-furans Pentachlorophenol Pentafluorobenzyl Resin acids 2,4,6-Trichloroanisole Tetrachloro dibenzo dioxin Totally chlorine- free 2-(Thiocyanomethylthio)-benzothiazole Total organic carbon Volatile sulphur compounds Volatile organic compounds... 

Other compounds, such as 2,4,6-trichloroanisole (TCA), 2-isopropyl-3-methoxypyrazine and 2-isobutyl-3-methoxypyrazine, were found downstream of a pulp mill effluent, and were considered as off-flavours. These compounds are by-products of chlorination, or can be produced by actinomycetes or other biota [74]. 

Evans, T.J., C.E. Butzke, and S.E. Ebeler. 1999. Analysis of 2,4,6-trichloroanisole in wines using solid-phase microextraction coupled to gas chromatography mass spectrometry. J. Chromatogr. A 786 293-298. 

Dichloroanisole 2.3.6- Trichloroanisole 2.4.6- Trichloroanisole 2.3.4.6- Tetrachloroanisole Pentachloroanisole 2.4.6- Tribromoanisole Geosmin 2-Methylisoborneol l-Octene-3-ol Octa-1,3-diene a-Terpineol 4.4.6- Tri methyl-1,3-dioxane... 

However, is not the analysis of minor wine volatiles that still presents difficulties. With the level of sensitivity and automation of the analytical techniques, the determination of many odorants at /rg/L level is a simple analysis. The difficulties come when the analytes of interest cannot be easily determined using a single non-selective-preconcentration step. This will happen when the analytes are difficult to extract because they are very polar and/or not very volatile or when they are present at very low levels. The concentration level at which the analysis of an aroma compound becomes difficult is related to its polarity and to the quality of its mass spectrum. Eor instance, the analysis of 2,4,6-trichloroanisol (TCA) at, let s say, 20 ng/L is not a very difficult analysis, because this molecule is quite nonpolar (easily extractable, relative volatile) and has a mass spectrum with abundant high mass ions.In contrast, the analysis of methional or of sotolon at 1 /rg/L is quite difficult because these compounds are very polar (difficult to extract, not very volatile) and their mass spectra lack powerful ions. For these difficult analytes, some of which are very important wine impact aromas, specific strategies must be developed ... 

Cork flavor, or the olfactory defect caused by moulds, is the commonest of the undesirable flavors found in wine. In most cases, the cork is responsible for tainting wine with 2,4,6-trichloroanisol (TCA) (Tanner et al. 1981). However, barrelled wine may also be contaminated with 2,3,4,6-tetrachloroanisol (TeCA) that can be present in the damp atmosphere of wine cellars in the presence of woods treated by polychlorophenols. TCA has a slightly different aroma than TeCA but the two contaminants are often confused. Another possibility is that the cork itself may be contaminated by other corks (TCA) or by TeCA. 

Cork taint is a musty/moldy off-odor in wine. It is related to the cork stopper, a wine botde closure made from the bark of the cork oak (Quercus suher). In a correlation between sensory evaluation and chemical analysis, 2,4,6-trichloroanisole (TCA) has b n identified as a major impact component. In sensitivity tests of a group of trained wine judges, a geometric mean of the minimum detectable concentrations of TCA has been determined at 4.6 ng/L. 

Although over 100 volatiles from finished corks have been reported (2-3), the one component that has been identified 4) as the major cause for cork taint is 2,4,6-trichloroanisole (TCA). In a recent study of Australian wines (5), 100% of the tainted wines, assessed by wine industry personnel, had TCA at or above the sensory threshold. The European QUERCUS study found TCA to be responsible for a musty/moldy taint in at least 80% of cases when it was detected in bottled wines. This makes TCA the most significant impact compound in regard to cork taint, and consequently made it the focus of our analytical developments. 

The various contaminations in foods are due to the presence of compounds dangerous for consumer health or that affect organoleptic characteristics of the product. Ochratoxin A (OTA) and biogenic amines are dangerous for human health, and their legal limits are fixed in grape and wine. Due to their negative sensory properties and very low sensory thresholds, 2,4,6-trichloroanisole and ethylphenols have to be practically absent in wine, or present at as low a level as is possible. 

Careri, M., Mazzoleni, V., Musci, M. and Molteni, R. (2001) Study of electron beam irradiation effects on 2,4,6-trichloroanisole as a contaminant of cork by gas chromatography-mass spectrometry, Chromatographia, 53(9-10), 553-557. 

Riu, M., Mestres, M., Busto, O. and J. and Guasch, J. (2002) Determination of 2,4,6-trichloroanisole in wine by headspace solid-phase microextraction and gas chromatography-electron-capture detection,/. Chromatogr. A, 977(1), 1-8. 

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