The all-natural wine bottle cork harkens back to centuries of tradition and culture. The signature pop as is it sprung from the cold glass grasp of your favourite vintage is just one of the romantic elements infused in the enjoyment of wine. It is both nostalgic and sentimental but is it necessary?
Over the last decade or so in South Africa, we have seen screw tops grow in popularity. They are quicker and easier to open and don’t require an unwieldy contraption to complete the task. Screwcaps seal better than cork which is porous by nature and prevent air from getting to the wine and spoiling it.
If you’ve been asking yourself these questions or it’s been the subject of a lively debate around the dinner table, then read on. In this post, we’ll look at some of the pros and cons of each as well as what oenology says to discern fact from fiction.
The basic purpose of wine bottle closure is to keep the wine in and oxygen out until you are ready to drink it.
You may have come across a recipe that calls for the use of leftover wine and wondered where one would buy such a thing. It might be handy to note that some people keep unused wine for cooking. Overexposure to oxygen quickly makes wine unpalatable for drinking but sufficient for cooking. Many a chef would disagree, but this is not that article.
That said, let’s get into more detail on both cork and screw tops to see how they compare.
Natural cork is harvested from cork oak trees that grow in the Mediterranean and the Iberian Peninsula, with Portugal being the largest producer globally. Having been around for thousands of years, natural cork stoppers have been found in ancient Egyptian tombs, albeit for entirely different reasons.
As a natural, regenerative product, cork is infinitely sustainable. The cork oak tree is the only tree able to regenerate its bark. This contains the cork and protects the tree from disease. They are carefully harvested every 7-9 years have an average lifespan of 200 years. This means that each cork tree can be harvested at least 17 times in its life.
This incredible product is incredibly versatile. Its uses range from wall, floor and roof tiles, to shoes, fishing rods and of course wine stoppers and more.
Natural cork wine stoppers.
Cork’s porosity allows minuscule amounts of oxygen to penetrate the cork and enter the wine. Contrary to popular belief, this is actually beneficial to certain wines. In particular, tannic wines which need time in the bottle to soften, benefit from the small amounts of oxygen that cork allows to pass through.
It’s not without its faults though. Natural cork suffers some negative side-effects such as trichloroanisole (TCA, commonly referred to as “cork taint” or wine being “corked” and “broken cork”). Easily recognised by its nasty aromas of mould, vinegar and must as well as a weak, dull taste.
Oenologically speaking, TCA develops when natural fungi come into contact with the chemical products used to disinfect the cork during the manufacturing process.
The dreaded broken cork phenomenon
This happens when the wine opener accidentally pierces through the cork or you accidentally push the cork all the way into the bottle, leaving the cork crumbles in the bottle your glass. When this happens, it’s best to strain the wine before drinking it to make sure every piece of cork is removed.
If a piece of the cork is still stuck in the bottle after breaking off, there’s no reason to panic. Simply screw the wine opener back into the cork without pushing it all the way through and gently pull the broken piece out.
Created in the 1950s by a French company called Bouchage Mecanique, screw tops are made of aluminium and usually have a small plastic liner on the inside to help seal the bottle.
Sure, twisting a cap lacks the romance of pulling a cork, but screw tops work wonders to eliminate the risks of cork taint and broken cork because they don’t let any oxygen in. This is also why they are typically used as a closure for many white wines and fruity reds that are intended to be drunk young.
Many winemakers that screw tops are appropriate for high-quality premium wines and certain wine regions are renowned for using screw caps. About 90% of wine closures used in New Zealand, including premium wines, are screw tops.
So, while many of us prefer the pop of the cork, perhaps the crackling of a screw cap is just as romantic to others. Either way, it is not necessarily an indication of the quality of the wine.
In fact, certain screw caps are manufactured with calculated levels of “oxygen ingress” over time while natural corks are inherently variable with their oxygen ingress rates.
Pros & Cons: Corks and Screw Tops
- Creates a super tight seal while still letting some oxygen in to develop the wine in the bottle
- Centuries of history and a sense of tradition
- The unmistakable sound of a cork popping
- The Coravin wine preservation system can be used on natural cork (incompatible with screw tops)
- Biodegradable, therefore not harmful to the environment
- Sustainably produced (although not locally)
- Prone to cork taint
- More difficult to open and require a corkscrew
- Prone to cork break, especially when old and crumbly
Screw Top Pros:
- Quick and easy to open; great for portability after opening
- Seals completely and doesn’t let oxygen in, which means the wine stays fresh for longer
- No threats of cork taint and cork break
Screw Tops Cons:
- Not compatible with the Coravin technique of wine preservation
- Lack of oxygen ingress can result in reductive aromas like a burnt match stick, cabbage and rubber
- Lacks the historical charm and romance of pulling a cork
- Adds more plastic to the environment
- Not biodegradable
The final verdict:
The cork versus screw top debate is not as simple as it seems. Each style of closure carries its own set of pros and cons and should not dissuade you from any particular bottle of wine. Screw top technology has improved to the point that it is no longer an indication of plonk and can be used with great success for premium wines.
As to which is better?
I have my thoughts, why not share yours in the comments.