Chemistry of Cork Taint

After reading George Taber's book To Cork or Not To Cork, I looked up a few references that were mentioned in the book in order to learn more about the chemistry of cork taint. As mentioned below in the book review, in 1981, Hans Tanner and his colleague Carla Zanier, used GC-MS (gas chromatography-mass spectrometry) to identify the offending compound of cork taint to be 2,4,6-trichloroanisole or TCA, which smells to many like wet cardboard having a musty or moldy off odor. The reason why TCA is so problematic is that it has a very low threshold of detection. Anyone can detect TCA at a level of 100 parts per trillion (ppt or nanogram/Liter), nine out of 10 can detect it at a level of 30 ppt, and at 10 ppt, half of the testers can detect TCA.¹
There is a family of chloroanisole compounds that can lead to cork taint, but does not necessarily have to come from cork itself.

Pentachloroanisole was found in huge inventories of French wines in the 1980's. The offending material was traced to the chlorine-based pentachlorophenol, one of the compounds in wood preservatives being used in the wineries during that time.
In 2003, Hanzell Winery in Sonoma, a producer of world class Pinot Noir and Chardonnay had a problem with TCA in their wines. Rather than trying to prevent word of TCA contamination from reaching the public, Jean Arnold the winery president shared her story with the public. TCA contamination was traced to the prolonged use of chlorinated sanitation products. The TCA taint was found not only in the wines, but in the winery where chlorine was being used. Arnold's honesty, grace and leadership translated into trust and leadership in the Hanzell brand.²
The question is "How does this cork taint develop?" In the case of cork itself, the starting compound called "phenol" is found in lignin, in the cork bark. The process of disinfecting the cork bark using chlorinated bleaching compounds transforms the phenol into 2,4,6-trichorophenol (TCP), then microbial action on the TCP yields 2,4,6-trichoroanisole.³

These days, corks are no longer treated with chlorine and Winery Sanitation Workshops strongly advise against the use of any chlorinated cleaning agents for sanitizing the winery environment.
References:
1. George M. Taber, To Cork or Not To Cork, Scribner, 2007, pg. 33, Scribner, 2007, pg. 33.
2. Michael Fineman, "Brand Promise Fulfilled", Wines and Vines, February, 2013, pg. 62-64. See also, George M. Taber, To Cork or Not To Cork, pg. 181-191. 3. Carlos Macku, Ph.D. and Kyle Reed, Ph.D.,Factors Affecting Closure Selection. Practical Winery and Vineyard Journal, Winter, 2011.
Additional Information:
Dr. Alan Limmer, Cork as a Closure--Post-Bottling Reduction and Permeability Performance, Napa, June, 2006.
María Luisa Álvarez-Rodríguez,1 Laura López-Ocaña, José Miguel López-Coronado, Enrique Rodríguez, María Jesús Martínez, Germán Larriba, and Juan-José R. Coque1, Cork Taint of Wines: Role of the Filamentous Fungi Isolated from Cork in the Formation of 2,4,6-Trichloroanisole by O Methylation of 2,4,6-Trichlorophenol, Appl Environ Microbiol., 2002, December; 68(12): 5860–5869.
All structures were drawn by the freely available drawing program from ACD Labs called ACD/ChemSketch Freeware.