The science of corking
My brother is a chef. He’s been a chef for a good ten years now, and he has imparted a fair amount of wisdom unto me in that time. He introduced me to the basics, such as why we add salt to food, and that sort of thing. Things I just didn’t really get until then. Sometimes, he’d tell me about something actually really interesting. Corking is one of those things.
Apparently, wine can go off. The thing is, there’s this whole idea of wine getting better with age. And very often, this is the case. Fine wines can be intentionally aged to add subtle changes to the flavour of the wine, and usually removes some of the harshness. However, given enough time, any wine will go off. Except, in the wine world, this is called corking.
When those not wholly involved with the culinary industry hear the word corking, it brings up images of bits of cork floating about in the wine. This isn’t the case. Corking, or cork taint, is caused by the above compound, 2,4,6,-trichloroanisole, or TCA. So here’s what typically happens:
A group of chemicals called chlorophenols are absorbed by cork trees through pesticides and wood preservatives, which automatically suggests that the rate of corking in wines has increased largely in recent times, when spraying plants with chemicals has become commonplace. When chlorophenols react with natural airborne fungi in the air, they form chlorinated anisole derivates, or TCA.
It is the presence of TCA that taints the wine, and we say that a wine ailed by TCA is corked. The nuisance of all of this is that you can only tell if a wine is corked after is has been produced, bottled, aged, and opened. After all of that has been done, it just seems like a great waste of good grapes.