Many people in the Unites States still equate a screw cap on wine with low quality, which is why the traditional cork is still the most prevalent wine closure device in the market. However, screw caps can now be found on more than 35% of bottles on the market. You may notice that many Australian and New Zealand wines in particular use screw caps. That’s because the screw cap was invented in Australia by the winemaker for Yalumba. In addition, there are other alternatives, such as synthetic corks. Let’s take a look at the pros and cons of some different wine closure devices.
- It’s romantic and traditional. There is something inherently appealing about popping a cork out of a wine bottle.
- It’s a renewable resource. The trees from which cork is harvested regenerate and have a lifespan of 200 years, producing cork for thousands of bottles.
- They are perfect for age-worthy wines. Cork allows trace amounts of oxygen into the bottle, which helps an age-worthy wine mature over time.
- Cork taint, or TCA. Cork is susceptible to contamination from a chemical compound that can transfer into the wine. It’s not harmful, but does impose aromas of wet cardboard or damp basement into the wine, making it unappealing. It is estimated that 10% of all bottles on the market are affected by cork taint.
- Cork can dry out and crumble over time. I’m sure many of you have experienced a cork that splits during removal, leaving behind cork dust and debris in the wine.
- Variability. Since cork is a natural product, there can be minor variations from one cork to the next, including how much oxygen can seep through into the wine. A minuscule amount of oxygen can be beneficial, but too much can oxidize the wine, prematurely turning it to vinegar.
- Cork is expensive – up to three times more expensive than screw caps – and that cost is added into the price of the wine.
- Each screw cap is manufactured to detailed specifications, so operate and perform in a consistent manner.
- Cork taint is non-existent with a screw cap, maintaining the quality of the wine.
- Screw caps do not let any oxygen into a wine, so they are particularly beneficial for young white wines that are meant to retain freshness and their signature fruity character. This may also slow the aging of red wines, allowing them to be cellared longer.
- They are more affordable.
- Screw caps are easy to open with no need for corkscrews or expensive opening devices.
- Negative environmental impact. Screw caps are made of aluminum, a material that needs to be strip-mined using practices that pollute air and water, and generate a lot of waste. Although screw caps can be recycled, most end up in the trash.
- Although screw caps prevent cork taint, they are susceptible to Reduction. Reduction occurs when there is too little oxygen contact, increasing sulfur dioxide levels and causing the wine to have a rotten egg smell.
- No risk of cork taint and provide consistent/predictable oxygen transfer rates.
- They won’t degrade, dry out or crumble.
- They are more affordable than both corks and screw caps.
- Negative environmental impact. They are often made from oil-based plastics, so are not biodegradable or sustainable. Some, but not all, can be recycled. There are plant-based alternatives that are sustainable, but they are expensive and not widely used.
- They are very hard to open and almost impossible to put back into the bottle to re-seal.
- They may give off a chemical odor.
Screw caps are a great option for young, fresh, vibrant wines, as they will protect your wine from oxygen that saps fruity flavors and aromas.
Technological improvements in cork production have reduced the incidence of cork taint, so it is not a terribly common occurrence. Yet the benefits of some minuscule oxygenation for wines you intend to cellar for a while favor the use of cork or synthetic cork. If you intend to purchase an age-worthy wine and lay it down in your cellar for several years, cork or synthetic cork is likely your better option.
Since the great majority of wine consumers drink their wines young, usually within 6 months of purchase, In the end, you’re in good hands regardless of the wine closure. So pop the cork or twist the screw cap and enjoy!