State-of-the-Art Knowledge about 2,4,6-Trichloroanisole (TCA) and Strategies to AvoidCork Taintin Wine

Abstract

Cork stoppers have been used for many centuries to seal wine in various vessels. Therefore, corks have become a traditional part of wine packaging in many countries and still play an important role for the entire wine industry. Nowadays, there is a wide option of bottle cork stoppers on the market, such as natural corks, agglomerated and technical stoppers (1 + 1), etc. These cork closures have a number of advantages, including positive sustainable and ecological aspects. Natural cork material can also be responsible for cork taint, which imparts musty/moldy or wet cardboard off-odors to the wine. However, corks are not the only source of cork taint in wine, as will be shown in the present chapter. Over the past decades, a number of compounds have been detected that can contribute to the cork taint. Among them, haloanisoles play a major role, in particular 2,4,6-trichloroanisole (TCA), which has been shown to be responsible for 50–80% or more of musty defect cases in wine. Currently, the cork and wine industries have developed a number of tools and technologies to effectively prevent cork tait in wine or to remove it if the wine is already contaminated. These practical as well as analytical questions about the TCA defects are the subject of the actual chapter.

Electron ionization induced fragmentation pathways of trichloroanisole

“…The presence of TCA in wine and cork stoppers leads to sensory defects, mostly characterized by an unpleasant musty, mouldy or earthy odour which is known as ''cork taint''. [1][2][3] Its formation can result from the microbiological methylation of chlorophenols through the process of O-methylation of 2,4,6-trichlorophenol (2,4,6-TCP) by filamentous fungi [3][4][5][6][7] or from reaction pathways associated with other fungi such as Penicillium species. 1 The molecule has a low organoleptic threshold value (B4 ng L À1 ) and it is estimated that 70% of tainted cork is contaminated by TCA.…”

Distribution of 2,4,6‐Trichloroanisole in cork stoppers

“…), either through direct contact or contaminated vapor phase, during winemaking and cellar aging. [5][6][7][8] All TCA found in cork is produced by microorganisms that lived in cork, mainly filamentous fungi. When these fungi encounter halophenols (widely used in the past as pesticides), a defensive biochemical reaction known as biomethylation occurs resulting in haloanisoles, which then persist in cork for a very long time.…”

“…When these fungi encounter halophenols (widely used in the past as pesticides), a defensive biochemical reaction known as biomethylation occurs resulting in haloanisoles, which then persist in cork for a very long time. [8][9][10][11] Part of these contaminants can withstand all stages of cork manufacturing and subsequently be released into the wine after bottling. 7,12 Although several haloanisoles can be produced and found in cork, TCA is the most common.…”

“…In fact, wine can also be tainted by other materials (wood barrels, filters, etc. ), either through direct contact or contaminated vapor phase, during winemaking and cellar aging 5–8 …”

“…All TCA found in cork is produced by microorganisms that lived in cork, mainly filamentous fungi. When these fungi encounter halophenols (widely used in the past as pesticides), a defensive biochemical reaction known as biomethylation occurs resulting in haloanisoles, which then persist in cork for a very long time 8–11 . Part of these contaminants can withstand all stages of cork manufacturing and subsequently be released into the wine after bottling 7,12 .…”