There is a long standing multi-step procedure to opening a bottle of wine, especially when it is being done table side during a meal. One of those steps is for the wine steward to dramatically present the cork to the person who ordered the wine so they may inspect it. Part of that inspection includes sniffing the cork. This is done to see if there is any cork rot, which would indicate that the wine has "turned" or gone bad, but the truth is, most people would not be able to make that judgement based on smell, and could actually better judge the quality of the wine simply by looking at and squeezing the cork.
All of this is quickly becoming a moot point as natural corks are being replaced by synthetic corks and metal screw tops. The screw tops were actually the earlier introduction as a cork replacement as wineries were looking for a cheaper alternative. This alternative was looked down upon by most wineries, and from the beginning, a screw top was associated with cheap wines, typically fortified wines such as Mad Dog and Thunderbird.
The first change in perception started in the late 1960's with the creation of the Stelvin Enclosure. What set this apart from other screw tops was that it had a second part that rested between the bottle and the top. This second part was a plastic neutral lining that kept the metal from interacting with the wine. Created to look like a traditional foil covered cork, the next reason for resistance from major wineries was that it did not allow for small exchange of oxygen that a real cork did. Today, however, these enclosures are built to do even that, allowing a wine to bottle age appropriately.
Another move in the closure industry has been creating synthetic corks. This move became popular out of necessity, as the explosion in wine popularity during the 1980's led to a shortage of available corks. As cork manufacturers tried to fill that need by creating inferior products, many bottles suffered cork taint and winemakers needed an alternative on the fly that did not have the stigma of a screw top.
Today, more wines than not feature something other than cork. All Australian wines are screw tops, and most wines under 30 dollars will be synthetic. Small batch wineries that are looking to save money and protect their product are increasingly turning to these synthetics. These are more predictable than a natural cork, and the small wines and wineries of California cannot afford to lose a substantial part of their limited output to cork taint.
This brings us back to dinner and the wine steward opening the bottle. If you want to have fun, sniff whatever was covering the wine, but to judge the quality of the bottle, all you really need to do is take a taste.
Jack Terry is a freelance writer who focuses on travel, lifestyle and food and beverage, and has been writing for over 20 years. http://www.wineclubworld.com