Cyclic voltammetry: A tool to quantify 2,4,6-trichloroanisole in aqueous samples from cork planks boiling industrial process

• Published in: Talanta (Oxford) 2013-12, Vol.117, p.438-444
• Main Authors: Peres, António M., Freitas, Patrícia, Dias, Luís G., Sousa, Mara E.B.C., Castro, Luís M., Veloso, Ana C.A.
• Format: Article
• Language: English
• Subjects: 2,4,6-trichloroanisole; Anisoles - analysis; Boiling; Cork; cork stoppers; correlation; Cyclic voltammetry; detection limit; Economics; Electrochemical Techniques - economics; Electrochemical Techniques - methods; Food Contamination - analysis; Food Industry; gas chromatography-mass spectrometry; Hot Temperature; Humans; industrial applications; Limit of Detection; Methodology; off flavors; Plant Bark - chemistry; Portability; pretreatment; Reproducibility of Results; Solvents; Standard addition method; stoppers; Voltammetry; Water - chemistry; Wine - analysis; wine industry; Wines
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2013.09.039

Chloroanisoles, namely 2,4,6-trichloroanisole, are pointed out as the primary responsible of the development of musty off-flavours in bottled wine, due to their migration from cork stoppers, which results in huge economical losses for wine industry. A prevention step is the detection of these compounds in cork planks before stoppers are produced. Mass spectrometry gas chromatography is the reference method used although it is far beyond economical possibilities of the majority of cork stoppers producers. In this work, a portable cyclic voltammetry approach was used to detect 2,4,6-trichloroanisole extracted from natural cork planks to the aqueous phase during the cork boiling industrial treatment process. Analyses were carried out under ambient conditions, in less than 15min with a low use of solvent and without any sample pre-treatment. The proposed technique had detection (0.31±0.01ng/L) and quantification (0.95±0.05ng/L) limits lower than the human threshold detection level. For blank solutions, without 2,4,6-trichloroanisole addition, a concentration in the order of the quantification limit was estimated (1.0±0.2ng/L), which confirms the satisfactory performance of the proposed methodology. For aqueous samples from the industrial cork planks boiling procedure, intra-day repeatabilities were lower than 3%, respectively. Also, 2,4,6-trichloroanisole contents in the aqueous samples determined by this novel approach were in good agreement with those obtained by GC–MS (correlation coefficient equal to 0.98), confirming the satisfactory accuracy of the proposed methodology. So, since this novel approach is a fast, low-cost, portable and user-friendly method, it can be an alternative and helpful tool for in-situ industrial applications, allowing accurate detection of releasable 2,4,6-trichloroanisole in an earlier phase of cork stoppers production, which may allow implementing more effective cork treatments to reduce or avoid future 2,4,6-trichloroanisole contaminations of wine. •Wine off-flavours may be due to the presence of 2,4,6-trichloroanisole (ng/L level).•2,4,6-TCA migrating from cork stoppers to wine is responsible for high economic losses.•Portable cyclic voltammetry is used to detect 2,4,6-TCA in cork planks boiling solutions.•Detection, quantification limits were lower than humans detection limit threshold.•The accuracy 2,4,6-TCA analysis in industrial samples was similar to that of GC-MS.