Natural, Agglomerate, Altec/Synthetic, which is the best cork?

[abefroman]

Natural, Agglomerate, Altec/Synthetic, which is the best cork?

 

[surlees]

IMO, it depends on the wine being bottled. For a red that will be aged over a year, I use a premium natural cork. These are more expensive, but last longer and are breathable which supports micro-oxygenation.

Second to the premium natural cork in quality are the 1+1 corks with slices of premium cork glued to each end. I don't use them, but many people do.

I use synthethic corks for my white wines. Synthetic corks don't breathe, but that's not really important with most white because they usually are consumed within a year or so.

Alot of agglomerate corks are used by home winemakers, but I don't use them because these seem to cause the most problems. They will disintegrate more readily than other types. If using agglomerate, Altec, is the highest quality brand.

There are other kinds of corks and I'm sure that some of these will be favored by other posters, but I have narrowed my usage to premium naturals and synthetic for the above reasons.

Fred

 

[abefroman]

Really? Breathable is good?

That won't make the wine oxidise?

 

[surlees]

Really? Breathable is good?

That won't make the wine oxidise?

No, we're talking micro-oxygenation, not oxidation. This is the reason all high quality commercial wines still use natural corks, not synthetic, agglomerate, or screw-cap.

Fred

 

[Wade E]

Like said above it really depends on afew things. If you have very good cellaring conditions then natural corks are great but you also need the very best natural corks as some of them are pure garbage. If you have terrible cellaring conditions then I would say synthetic would be the best as they dont let anything in or out and yes most corks do breathe sort of like a wine barrel letting out and breathing in and this lets a wine age properly unlike synthetics which you really should bulk age for awhile to let your wine age. I prefer the perfect agglomerate as they are a combination of synthetic and natural cork to not get moldy as natural corks can do easily but still let your wine breath a little. If using synthetic though youll want to use a Italian floor corker or a corker with brass jaws as the plastic jaws are good for all corks except synthetics as they are much harder to compress leaving creases in the sides from a plastic jawed corker which can lead to leaky corks. Some corks like the 1+1 or similar actually are natural cork with synthetic discs at the front and back of the cork.

 

[JohnT]

Read the book - To cork or not to cork by George Tabor.

In short, it depends.

Today, it seems that the push for synthetic or screwcaps is due to "cork taint" or TCA. In the past, A winery could expect to have as much as 4% of their wines ruined by TCA. Today, a lot more is understood about TCA and the cork manufacturers are not taking careful steps to reduce its occurence.

The major problem (other then the cost) is that synthetic closures can not mimic the properties of natural cork. Natural cork have a very specifie "bounce back" quality or spunginess that (as yet) can not be duplicated.

Natural cork also has a property that allows very minute amounts of O2 to seep through. This exact amount of O2 is the biggest contributor (but not only) to a wine's maturation.

Synthetic corks allow too much O2 to seep through. Wineries have found that wines aged for over 6 years on synthetic cork have a high tendency to oxidize (to the tune of 60%). The other negative quality is that there is far less "give" in the material itself. You will find it rather easy to find someone that has broken a corkscrew while extracting a synthetic cork. For these reasons, the synthetic cork's days are numbered. Wineries are now trending away from synthetic corks in favor of screwcaps and natural corks.

Screwcaps are good, but only provide a hermetic seal. In other words, screwcaps do not allow any of the micro oxidation that corks do. This is not a problem for winemakers that want to age wine "as is". Professional wineries that use screwcaps tend to age their wines in alternate containment (such as barrels) until the desired level of maturation is reached. Once sealed with a screw cap, most of the maturation is halted, preserving the wine "as is" for a more extended period of time.

The one big negative with screwcaps is, again, there is no micro-oxidation (M-O). M-O allows for the evacuation of many off orders that naturally happen in winemaking. If any such compounds form or are present after the screwcap is applied, then they will be trapped in the bottle. With cork, these compound can actually seap out of the bottle or even react with the M-O.

Yet another problem with screwcaps is the cost of the devices used to apply the screwcap to the bottle.

So IMO, Corks are always the preferred way to go. In choosing the type of cork to go with, the rule of thumb should be "the bigger the piece, the better". At the most preferred end of the scale (and also the most expensive) is the high quality whole cork. At the less preferrred end of the scale (and least expensive) is the "bound corkdust" variety.

(need to give my fingers a rest on this one)

 

[ibglowin]

Actually the Stelvin Screw Cap has been perfected to allow various levels of micro-oxygenation just like the finest of natural corks depending on what material type the liner is. Depending on the varietal and wine type a winery can select a cap with anywhere from zero oxygenation to quite a lot if needed. This Summer I purchased several bottles of very limited production Hogue Cellars Terroir wines (one Merlot and one Bordeaux Blend) and both were sealed with Stelvin closures. While not quite as romantic to open the seal is gaining quite a following, even with more expensive wines in some instances.

Read the book - To cork or not to cork by George Tabor.

In short, it depends.

Today, it seems that the push for synthetic or screwcaps is due to "cork taint" or TCA. In the past, A winery could expect to have as much as 4% of their wines ruined by TCA. Today, a lot more is understood about TCA and the cork manufacturers are not taking careful steps to reduce its occurence.

The major problem (other then the cost) is that synthetic closures can not mimic the properties of natural cork. Natural cork have a very specifie "bounce back" quality or spunginess that (as yet) can not be duplicated.

Natural cork also has a property that allows very minute amounts of O2 to seep through. This exact amount of O2 is the biggest contributor (but not only) to a wine's maturation.

Synthetic corks allow too much O2 to seep through. Wineries have found that wines aged for over 6 years on synthetic cork have a high tendency to oxidize (to the tune of 60%). The other negative quality is that there is far less "give" in the material itself. You will find it rather easy to find someone that has broken a corkscrew while extracting a synthetic cork. For these reasons, the synthetic cork's days are numbered. Wineries are now trending away from synthetic corks in favor of screwcaps and natural corks.

Screwcaps are good, but only provide a hermetic seal. In other words, screwcaps do not allow any of the micro oxidation that corks do. This is not a problem for winemakers that want to age wine "as is". Professional wineries that use screwcaps tend to age their wines in alternate containment (such as barrels) until the desired level of maturation is reached. Once sealed with a screw cap, most of the maturation is halted, preserving the wine "as is" for a more extended period of time.

The one big negative with screwcaps is, again, there is no micro-oxidation (M-O). M-O allows for the evacuation of many off orders that naturally happen in winemaking. If any such compounds form or are present after the screwcap is applied, then they will be trapped in the bottle. With cork, these compound can actually seap out of the bottle or even react with the M-O.

Yet another problem with screwcaps is the cost of the devices used to apply the screwcap to the bottle.

So IMO, Corks are always the preferred way to go. In choosing the type of cork to go with, the rule of thumb should be "the bigger the piece, the better". At the most preferred end of the scale (and also the most expensive) is the high quality whole cork. At the less preferrred end of the scale (and least expensive) is the "bound corkdust" variety.

(need to give my fingers a rest on this one)

 

[JohnT]

True, stelvin has a variety of liners that they have only recently started selling. Used to be that the liners were of only one type of plastic that provided only a hermetic seal.

You should try a stelvin closed wine after it has aged 10 years. It is quite remarkable.