Something screwy has happened to the wine world.
A decade ago the sound of a wine bottle opening in a restaurant was predictable: the satisfying “pop” of a cork being pulled out. Today, it’s just as likely to be the “skritch” of a screwcap being turned.
Many people like the ceremony of a cork. But is it a better way to close a bottle? Increasingly, wineries are saying no — and consumers are agreeing. Here’s a look at how we got here.
Cork: The natural solution
Wine has been made for thousands of years, but cork closures on wine bottles have only been the standard since the 1600s. That was when wine bottles began to be standard sizes, so corks could be standardized to fit them.
Cork is amazing. It comes from the outer layer of a cork tree and it doesn’t kill the tree to harvest it, so it’s completely sustainable. It’s flexible enough to be compressed to fit inside a wine bottle so that it can block the entire diameter. Other natural substances used before, including cloth and leather, cannot possibly give as tight a seal.
Cork is slightly porous so a tiny amount of oxygen enters the bottle. Oxygen is what causes wine to age. If you could store wine in a complete vacuum, it might taste the same 10 years from now. But that isn’t what most people want when they put a wine aside for 10 years. A very tiny amount of oxygen — not enough for the smallest creature you can imagine to live on — will help the bottle develop more complex flavors and softer tannins, which will make it taste richer.
Cork was the miracle product of the 17th century, and people were pretty satisfied with it until about 30 years ago.
But cork has several flaws. One is that occasionally it contains a chemical called TCA that ruins a wine, causing it to taste like wet cardboard. If TCA is in the cork (this happens somewhere between 1% and 5% of corks), TCA increases over time in a closed bottle. This is what happens when people say a wine is “corked.” It won’t hurt you to drink a corked bottle, but it’s not pleasant — and we drink wine to enjoy it.
Another important flaw that people accepted until very recently is that, as a natural product, corks are very slightly different from each other, which means they allow oxygen at slightly different rates. The amount of oxygen that passes through a cork is so tiny that for a year or two, a slight difference in rate doesn’t matter. But over several years, two bottles of wine that are supposed to be the same — same brand, same vineyard, same year, even from the same case — will taste very different. People always accepted this as a charming quirk of the wine world until there was a better solution.
Screwcaps: Not just for soft drinks anymore
Screwcaps have only been around on any product for about 100 years. They were invented in the early 20th century when glass bottle manufacturing became more mechanical. But they were slow to come to beverages because the seal wasn’t complete. As late as the 1960s, soda and beer bottles were usually closed with a crown cap that must be removed with an opener, unless you are a tough guy: then you can show off by pulling it off with your teeth, biceps, etc. Even today crown caps still exist because they have advantages over screwcaps, mainly that they are more difficult to damage in transit.
But by the 1970s, screwcaps on soda bottles were commonplace. They’re clearly much better for the consumer. They’re easy to open, with no special tool required. They’re easy to close so the bottle can be resealed. They are an evolutionary advance on corks and crown caps.
As screwcap technology improved, wineries in Australia and Switzerland became interested. Australian and New Zealand wineries always believed that Portuguese cork producers sent them their worst corks because wineries on the other side of the world, where no cork trees grow, had little choice but to accept them. The first screwcap trials for wine came in 1970. By the late 1970s Australian wineries started to use them, but customers resisted; they thought screwcaps made the bottle look cheap. The wine market wasn’t very sophisticated then. Americans drank more wine coolers than wine; Australians drank more sweet fortified wine than dry table wine. And the screwcaps weren’t very sophisticated either.
But by the 1990s, both the wine market and screwcap technology had come a long way.
What had been a big disadvantage of screwcaps — that they let in no oxygen at all, compared to the tiny flow through a cork — became an advantage when wineries understood it. Instead of pushing all of the air out of a bottle when filling it with wine, they left a little more air in a screwcapped bottle. Plus screwcaps have been developed to allow slight airflow if a winery wants it.
Today, screwcaps are superior to corks in just about every way. They’re easier to open and to reseal. They don’t contain TCA, so there is no “corked wine” problem. And wineries that have conducted extensive tests have shown that wines age more consistently in screwcapped bottles.
Wineries in Australia and New Zealand are the biggest fans of screwcaps, even for their most expensive wines. And wineries all over the world are following suit. In 2008, one Italian producer, Allegrini, even took the name of its appellation off its wine bottles because the appellation still required cork.
Cork still has a place in wine — it’s still an amazing natural product — but about the only thing corks still have going for them are tradition, ceremony, and that delightful “pop.” We may have to get used to salivating when we hear the “skritch.”