Soooo Much Cork

It's been a full February of Cork Sensory.  Everyday the lab bench has looked like this.

First, adorable Portuguese men strip the bark off of cork trees.  It takes about 7 years for the bark to be thick enough to Harvest.

They flatten the bark and literally punch the corks out.

Higher quality cork is punched as far from the outer bark as possible.  This is also more expensive because they have to wait more year between the harvests, but most TCA causing mold is more likely to be located on the bark.

Minimizing the occurrence of TCA in cork is a very important job and the final QC step in sending the wine off to the consumer.  Every cork company and winery does their own version of a cork soak.

At this cork company they soak their corks in a Neutral White Wine.  In my lab I use 10% ethanol.

While I was picking up my cork samples at the cork company, I noticed this instrument.  The corks are soaked in wine on one end and then corked into the plastic tubes to mimic being in the neck of the bottle.  Next, pressure is applied to simulate the passing of time and they get to see more quickly if a cork is likely to leak.

Ok, once I get the samples back to the lab, I get out my jars.  100 corks in 100 jars representing a lot of 50,000.

Each group of 20 represents a single bale of 10,000 corks.  If even 1 of the 20 corks smells like TCA to anyone in the winemaking team, we reject the bale and soak another one the next day.

 After all the corks are in, I fill the jars with 10% ethanol.

The corks are in contact with the liquid for 24 hours.  At that point I pour them out into glasses and the winemaking team comes to smell them.

 
It's very difficult to smell 100+ glasses and still be accurate at the end.  Your senses get accustomed to the aromas and you stop being effective after a short time.  The rose is from Valentines Day.


In addition to taking breaks, we also have coffee and citrus to cleanse the pallet, as it were, like at the perfume counter at a department store.

We don't all always agree on which corks have TCA, so if there is a question I will re-soak the cork and slip it into the next day's sensory to see if the team is consistent and they pick it up a second time.  The TCA in a cork comes into equilibrium with the liquid, so a tainted cork can be re-soaked many times.  Which also means you cannot soak the TCA out of a tainted cork and make it "clean", you just have to reject it.

Also, incase anyone hasn't seen it: SNL Cork Soakers

-Lucia

P.S. This is the 12L flask that I use to dilute my ethanol from 95% to 10%.  It's a pretty awesome piece of glassware.  I liked the way it made the tiny corks behind it look giant.