Cork has been used for thousands of years in products like flooring, shoes, bags, and wine closures. Wine corks come from the bark of the Quercus suber, also known as the Cork Oak tree. These trees take roughly 25 years to mature before harvesters can remove the bark by hand.
For centuries, cork remained the preferred wine closure because it allowed small amounts of oxygen to enter the bottle during aging. This gradual oxygen exchange can help wine develop complexity over time.
However, cork is a natural product. Because of that, no two corks are exactly the same.
One of the biggest challenges with cork is inconsistency.
The pores, elasticity, and density of each cork vary naturally. As a result, some corks allow more oxygen into the bottle than others. This inconsistency can lead to something called sporadic oxidation.
When excess oxygen enters a bottle, wine can develop:
Even slight imperfections in the bottle neck, corking equipment, or cork structure can affect the seal.
Another common issue with cork closures is TCA contamination, often referred to as a “corked” wine.
TCA (trichloroanisole) forms when chlorine interacts with naturally occurring molds found in cork bark.
Signs of a corked wine include:
Once you recognize the aroma, it becomes easy to spot. The wine industry estimates that roughly 5–10% of wines bottled under cork show some level of TCA contamination.
The screw cap was patented in 1889 by Dan Rylands in the UK, although wineries did not widely adopt the closure until much later.
Modern wine screw caps contain specialized liners that help control oxygen exchange. Different liner materials allow winemakers to customize how much oxygen enters the bottle over time:
Australia helped popularize screw caps in the 1970s, especially for high-end Rieslings. Since then, wineries around the world have increasingly embraced screw caps for both quality and consistency.
The truth is that both closures have advantages. However, screw caps offer several major benefits for modern winemaking.
Unlike cork, screw caps provide a nearly identical seal from bottle to bottle. This consistency reduces the risk of oxidation and spoilage.
Because screw caps are inert, they do not introduce TCA contamination into the wine. That means no risk of a “corked” bottle.
Heat can damage wine regardless of closure type. However, traditional corks can begin pushing out of the bottle when temperatures rise above 85°F, exposing the wine to additional oxygen. Screw caps handle pressure changes more effectively and remain tightly sealed.
No corkscrew required.
Screw caps make wine more approachable, portable, and convenient—especially for outdoor dining, picnics, and casual gatherings.
Aluminum screw caps are recyclable and often more affordable than natural cork and capsule combinations. Lower packaging costs can also help keep wine pricing more accessible for consumers.
One of the biggest misconceptions about screw caps is that wines cannot age properly under them.
In reality, many studies around the world have shown that wines under screw cap closures age just as well—and sometimes better—than wines bottled under cork.
At Suhru & Lieb Vineyards, we’ve proudly bottled our wines under screw caps since opening in 2008 and have seen excellent long-term aging results across many vintages.
While cork may feel more traditional or romantic, screw caps offer:
For us, the decision ultimately comes down to protecting wine quality and ensuring every bottle tastes exactly as intended.
And honestly? There’s something satisfying about simply twisting open a bottle and getting right to the good part. 🍷
