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The Great Debate: Whiskey Closures

Published on:

March 4, 2020

Written by Shelley Sackier, Director of Distillery Education, Reservoir Distillery.

There is nothing more satisfying than a rollicking good debate, in my opinion. Preferably fact-based and on a topic I’m hungering to know more about.

Since we are up to our eyeballs in “debate land” territory and our country feels more divisive than ever, I figure we should take advantage of the heightened state of information gathering our brains are working to maintain, and toss yet another subject of controversy at it – Whiskey closures.

It’s true, this may not be an issue causing insomnia for your patrons, but it’s a genuine concern for people working within the wine and spirits industry. The “best sealing practices” debate is more complex than one would think.

Finding the Right Fit: Cork or Screw Caps?

The choices used most widely now are:

  • Natural cork
  • Synthetic cork
  • Screw caps

Ultimately, “the right fit” comes down to science, cost, sustainability, and sensibility.

We know that both industries must consider OTRs – oxygen transmission rates. For cellar-worthy wines, the slow interaction with air is beneficial. Using natural cork, which allow volatile gasses to pass through the plant-based material, will help with the desirable aging process.

Wines meant to be enjoyed immediately are often capped with a screw top closure, as it’s a secure sealant and is less expensive than cork. Whiskey, on the other hand, has a different outlook: Barrels are for maturation, bottles are for preservation.


Natural Cork

Choosing natural cork to seal a bottle of whiskey has both risks and benefits. Let’s start with the cons:

  • Cork is expensive – it may add precious pennies to the overall cost.
  • There exists a firm debate over whether the cork bark harvesting industry is as carefully regulated as it once was. We add to this list the effects of climate change, making quality a growing concern.
  • TCA – 2,4,6-Trichloroanisole – is a chemical compound found in contaminated wood products responsible for “cork taint” in wines and spirits. If discovered to have infected the product, it creates a musty, wet cardboard aroma and flavor.
  • Natural cork, when used for high-proof spirits, can disintegrate, crumble, and lose sealing power.

However, the pros are also worth consideration:

  • Natural cork is recyclable.
  • Natural cork is visually appealing and contributes an authentic, historical feel to the bottle which can enhance the perceived quality of the wine or whiskey.


Synthetic Cork

Of course, there are other options. Synthetic cork offers a range of benefits:

  • It’s said to provide a tighter seal, thereby ensuring less evaporation and less chemical interaction with any volatile gasses permeating through the closure.
  • Synthetic cork is less expensive.
  • Synthetic cork – although not typically biodegradable – may be recycled if they are manufactured from plant-based materials (but even many of the plastic-based corks are recycled into shoes, bags, and flooring).
  • They do not break, disintegrate, mold, or crumble.
  • Studies are ongoing as to whether polyethylene – the plastic-based cork – can deliver off notes to wine or spirits, although the companies that manufacture these corks state there is no data to show this as true. For example, Tapi – one of the largest and longest running manufacturers of bottle closures – assures its customers via thorough lab analysis that their synthetic corks reveal no outgassing of contaminating odorants.

The biggest risk is consumer perspective. The decision to use synthetic cork may give consumers the perception of a “lower-quality” product, since it does not match expectations of the traditional and historical worth of authentic cork.

Screw Caps

Growing in popularity, screw caps share many of the same clear benefits as synthetic cork. However, it’s also important to note that they suffer from a larger carbon footprint than their counterparts – despite the rosy glow of their aluminum recyclability.


Top Notch Tips for Spirits-Worthy Sealants

The choice of bottle closure is one that deserves consideration, and when confronted by customers who question your preference, a careful response is the best option, as many of your patrons have distinct opinions and wish to be heard. Providing fact-based science helps reassure them of the myriad elements you weigh on the matter.

Of course, it also never hurts to offer your consumers a few sage tips to keep your spirits in their best condition:

  • Store bottles upright – especially if they have natural cork as their enclosure.
  • Keep spirits out of direct sunlight, and preferably in a dark, cool area.
  • Once there is more space than spirit in the bottle, consider transferring the whiskey to a smaller glass bottle or utilize preserving sprays.
  • We, at Reservoir Distillery, smile and suggest having a few friends over to finish off those last lovely drops.

Whiskey closures may not be as monumental a subject as the outcomes on healthcare, but you take great pains to create a whiskey your customers will love and one that will last. Give them permission to call their high-quality whiskey needs medicinal.

Chances are, no one will argue on that one.

Written by Shelley Sackier, Director of Distillery Education, Reservoir Distillery.

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