I have written about wine corks in previous articles, but something in a recent article I was reading caught my eye. It seemed like an update. I thought the information might be of interest, because the debate continues as to which is the better seal for a wine – a Cork or a Stelvin Screw Cap.

Enter Stephanie Jacobs. Stephanie is the assistant winemaker at Cakebread Cellars. She wrote a piece for her newsletter that I’d like to pass along, because she brings out some teaching points and does a good job developing a case for cork stoppers.

Here is what she had to say: Not long ago wine cork manufacturers were under siege from wine retailers, consumers, and critics for what seemed to be an unacceptable high percentage of “corked” wines. The term “corked” refers to cork taint caused by a chemical called Trichloroanisole (TCA), a naturally occurring compound that, at high levels, can cause an odor like moldy newspapers or wet cardboard, while simultaneously stripping away fruit flavors and aromas. TCA can arise from many sources, but relative to corks, it seems to derive from the interaction of naturally occurring molds in woods with chlorine that, until recently, were used to clean and bleach the corks. Beginning in the 1990s, the high incidence of corked wines led many vintners to switch to a screwcap or synthetic closure, especially for wines that that were not meant to be aged.

The reason for the choice of wine closure is important because it regulates the incursion of oxygen into the wine after bottling. This, in turn, affects how wines age. Cork closures are ideal for aging because they allow a very small, but consistent, amount of oxygen into the bottle which slowly matures a wine. This is especially important for wines like a Cabernet Sauvignon which can age well for many years, even decades. Synthetic corks allow more oxygen into the wine, perhaps maturing the wine faster than desired. Screwcaps allow the least amount of oxygen, which is fine for a wine meant to be consumed within a year or two of bottling, but not advantageous for more serious whites and age-worthy reds which gain complexity from exposure to a measured amount of oxygen.

Due to the high incidence of cork taint in the 1990s and 2000s, cork manufacturers were forced to work assiduously to develop better methods of cleaning and bleaching cork material. The hard work paid high dividends as the incidence of cork taint declined 95%. Wines now affected by cork taint are in the neighborhood of only 1%. The manufacturers, who own and run the cork factories, also own thousands of acres of trees that produce bark from which the cork material is harvested. The owners of the tree acreage had to go back as far as the soil that surrounds each tree and treat it, as this is also a possible area for harboring TCA. Using this “from the ground up” approach was absolutely the way to go to solve the problem. Cork bark is a renewable resource. The outer bark is only harvested once every nine years and a tree can live as long as 200 years. Once the bark is harvested there is no waste as modern methods of cork production have improved.

In her article, Ms. Jacobs mentioned some other sources of TCA. These sources include wine barrels, pallets, and cardboard materials. As a result, Cakebread Winery, and hopefully all the others, has installed monitoring and preventive programs to detect and eliminate TCA wherever possible.


I really must applaud Ms. Jacobs for her article. She clearly highlighted several facts that folks, for the most part, do not even think about until that awful moment when you open a bottle of wine and a cloud of cork taint fills your nose. She also made mention of the fact that oxygen is so important to the aging of wine. In a simple declarative sentence, she explained that lots of good things are happening inside the bottle when you bring home that very expensive Cabernet or Burgundy, lay it down for a number of years, and open it on the night of a special occasion. It is worth the wait.

I had an outstanding frame of reference for Ms. Jacob’s article when I had the opportunity to visit a cork factory in Portugal. Most people would let out a gigantic yawn at the thought of going to a cork factory. However, to a wine geek like myself, the tour was an enjoyable learning experience. If there’s one thing that left a permanent impression on me, it was the enthusiasm the management folks at the factory had for getting educational materials out to the public.

Cakebread wines are available in most Lowcountry retail stores and restaurants.