The recorking of an aged bottle of wine is today a rare practice - which consists of retiring an old, faulty cork of a wine bottle and replacing it (by the winery) with a new cork. Though the recorking of wine bottles has been going on for centuries, today recorking also known as ‘reconditioning’ of wine - takes place less often for several reasons.
The recorking of wine is done because at some point in time, wine corks deteriorate and lose their elasticity, structural integrity and tight seal inside the neck of the bottle. Air will enter into the bottle allowing the wine to evaporate, along with introducing additional oxygen into the wine, which will overtime, madérisé, damage and finally spoil your wine. For centuries, it has been commonplace to recork wines in most wine regions around the world.

 

In Bordeaux-France, they look to replace corks roughly every 30 years for wine which they were cellaring and for their top customers. Château Lafite Rothschild would operate clinics all over the world where they brought a recorking machine with them. Customers could request to have their bottles tasted and if ideal to be recorked at these clinics. Several other prominent wineries around the world also operate similar clinics. Plus some producers may recork older vintages of their wines if they are brought back to the winery.
Though recently in some countries the practice of recorking bottles for customers has almost been stopped, due to the possibility of fraud. The process of recorking or reconditioning wine is relatively simple. The wines are required to stand upright for a period of time to allow the sediment to float to the bottom of the bottle. The bottle necks are then cleaned with a brush and simple sterile clothe to ensure no dirt, unwanted particles or chemicals are allowed to enter into the wine during the recorking process. The cork is removed using a recorking machine or on some occasions with a ‘butlers-friend’ and steady hand. At this point in time, they will give the wine a thin layer of nitrogen, which will stop unwanted oxygen from entering the wine. Next, the person in charge of recorking the wine will inspect the wine making sure the taste of wine is as it should be for its age and development. They will check for problems with the cork, TCA, maderization or other potential problems or faults. If the wine is not sound, the bottle will be rejected and the owner will be encouraged to dispose of it. If the bottle belonged to the winery, the wine and the bottle will be discarded.
Then the winemaker or key representative from the winery will agree that the original bottle will be topped up. Meaning, additional wine from the same vintage, (when possible, or nearest vintage of a similar style) will be added to the bottle. Of course with vintages over 100 years of age it will be difficult if not impossible to find the same wine to top-up the bottle. In those rare cases, the wine could be topped with an old and hopefully similar vintage, else the winery could use a younger wine, from a vintage similar in character. In most instances, the customer or winery might start with a full 12 bottle case and use one bottle for topping-up. At the end of the process, once the wine has been recorked, the owner will be left with 11 recorked bottles (and sometimes a 375ml bottle). Please note, the original wine is not removed from the bottle during this process, as this keeps the potential exposure to oxygen at a minimum.
The bottle is then given a small dose of sulphur dioxide, SO2 to further protect the wine from exposure to air, caused by recorking the wine. Next the bottle is re-foiled and the process of recorking is completed. The bottle can be given a label or certificate, which will show the date the recorking took place and might also use the term ‘rebouchée’ - which is French for reconditioned, or in this case, recorked under the foil-cap.
Due to the introduction of nitrogen and SO2, the recorked bottle should not be opened for at least 3 to 5 years to allow the extra gas to dissipate. If you were to open a recorked wine shortly after this process, the wine would be mute and not display much, if any aromatic or flavour intensity or complexity.
The process and results of recorking wines has its fans and detractors. If a winery is planning on cellaring a wine for more than 50 or possibly 100 years, or if you have an old bottle that is already over 30+ years of age that you wish to age longer, recorking definitely makes sense.
It must be noted, the percentage of wine added (if from a younger, different vintage), can have a retarding effect of the natural development of the original wine. When compared with the original wine that has not been topped-up and recorked, this wine has more complexity and a more harmonious character. It must also be noted that generally - recorked bottles have in auctions been resold for less money than wine bottles with the original cork still intact.
If you are offered a bottle of wine that has been recorked by the owner, and not a winery that is qualified to do this, do not buy the wine whatever the price. Wine is fragile at the best of times. On the other hand, there is no fear about buying a wine that has been recently professionally recorked and certified. You can have confidence that the wine should be sound and able to age further and enjoyed when opened.
As an average, some wineries suggest replacing the cork every 20-30 years. Some recommend doing it after 15 years. Experts acknowledge that many wine corks last much longer than the 15 years, which is the minimum age at which many replace them.
Since a lot of wine in consumed within a much shorter period after purchase, this practice is not as wide spread as it once was. Though it is considered an important part of cellaring wine and guaranteeing its original quality as well as ideal aging. This is a preventive method that protects your wine investment from spoiling. By letting the original winemaker do the job, you are basically giving yourself the assurance of perfection. Also many enthusiasts would like to know how their wine is aging… well, during this process you can find out. This process will allow you to have a taste of your wine while being recorked. If the same vintage is not available, some companies offer to use tiny clear glass balls instead to compensate for the evaporated wine and bring the filling level in the bottle back to normal.
It should be pointed out that 15ml - 25ml of added wine represents only 2-3% of the 750ml bottle, and that it is thought to be well below the threshold, which no one will detect a difference in the original wine. Though typically 50-60mls is added to top-up a bottle, if from the same batch-vintage then there will be no problem, but if it is from a younger vintage then a noticeable difference could occur.
Some wineries offer this service to their loyal customers, with complementary clinics conducted approximately every few years. They provide you with an opportunity to meet and talk with the winemaker who will assess your wine. Remember, this process can be done to only a few wines produced by the winery and as long as it is at least 15 years of age. This will vary based on the wine (typically only their top wines get this service, as they need to be of a quality to age this long) and the wineries individual policies. Recorking aged wine is not for everyone. If you are not sure about the aging properties of your wine, you should contact the winery and get information particular to your wine in question.