Lettie Teague gives us our jumping off point again in a Wall Street Journal article dated September 12-13, 2015. Her article was about cork, both natural and synthetic, along with the other modern alternative bottle closures. The well-known problem with cork (since 1980) is TCA or 2,4,6-trichloroanisole, the musty/moldy off-odor affecting 6% of all wines with natural corks. In her article Teagues reports that the cork industry has spent more than two hundred million dollars in the last twelve years improving the cork-making process in order to remedy the TCA problem.
In the Teague article what caught my eye was the concept of "steam distillation" as a treatment for TCA in cork. On September 15th of '12 we wrote here about Flash Detente which is modern winery technology which flash steams grapes in order to reduce methoxypyrazine, the vegetal odor and taste in certain wines. Using the water in the juice of the grapes themselves in a vacuum chamber, the machine flash steams the berries to 160 degrees expelling the methoxypyrazine and other contaminants in the process.
In the steam distillation process, temperature sensitive aromatic compounds are removed from organic material. Cork, of course, is dry material so its "juice" couldn't be used like grapes in Detente but the question remains, could steam distillation be a corollary to Flash Detente applied to cork treatment?
SPME GC-MS stands for solid-phase microextraction for gas chromatography-mass spectometry. Whereas cork used to be cleansed with a chlorine bath, a treatment which is now believed to increase TCA, SPME GC-MS is a high tech wash that causes impurities to exit the cork and adhere to attractant material in the treatment. It draws TCA and other impurities away from the cork and to the treated material in the bath.
Advocates for SPME GC-MS and Steam Distillation believe TCA and other contaminants are reduced by 80%. Other treatments in use include supercritical carbon dioxide, microwave radiation, ozone treatment, and hydrogen peroxide washes, all of which will probably never be taken up here in the V&C blog.
Cork is still the closure of choice for the vast majority of winemakers around the world as it has been since the sixth century BC. It is also "green", releasing a quarter of the carbon dioxide in its production that screw cap production does. Cork also supports working families in a half dozen countries in Europe, Asia, and Africa. It is also frankly an everyday cultural touchstone for us in this industry so bully for the cork industry for tackling TCA!
This Thursday, October 8th between 5 and 7pm, Dmitry Paladino joins us with a tasting of fine wines from Argentina, California, Spain, and Italy. Dmitry brings an extensive wine knowledge packed into his ten year career to our tasting table so please join us for the event. We ask for a ten dollar donation which is applicable to a fifty dollar purchase.