Corks - look but don't smell: Guest Post by Nicolas Quillé MW - WineUncorked: Wine Reviews and Tips

The zealous wine drinker should view the cork from a bottle of wine as a provider of valuable information. How it's made and what it's been made of can suggest what value the producer put on the wine or the attention they put into preserving it and help us appreciate the wine's age and its integrity.

After the wine has been opened it is a good idea to have a quick look at the cork - but noses should be kept far away. If you want to sniff something then focus on smelling the wine rather than what has been used to stop the wine falling out of the bottle. The only professionals that smell corks are restaurant sommeliers that perform a quick quality control check for cork taint (the cork will smell musty or of wet cardboard and so will the wine). So unless you are a sommelier you do not need to smell the cork. It will also ensure you do not put a drop of red wine on the tip of your nose!

Wine professionals prefer to talk about wine bottle 'closures' rather than simply 'corks' as there are now various materials that can be used to stopper a bottle other than the shaped bark from a cork oak tree.

The choice of closure is often chosen in relationship with the price of the wine and the preservation objectives of the winemaker. Expensive red wines, that are made for long term aging, tend to have more expensive closures such as a long, well-formed 100% natural cork, while for age-worthy white wines a screwcap with a metal looking liner is used. Cheaper wines may use a plastic or an agglomerate cork closure made from small cork particles glued together. Producers fearing cork taint may use closures such as Diam (the trade name for the top of the range agglomerated cork) that have been thoroughly washed to remove any trace of this taint.

The age of the closure and its integrity are also useful to observe.

An older cork tends to be discolored and will have lost its elasticity. The estimated age of the closure should match the estimated age of the wine and any discrepancy could be an indication of counterfeiting. The integrity of the cork can lead you to smell for a potential fault in the wine. If wine seems to have seeped down the side of the cork this can indicate a wine has become oxidised while in the bottle.

A deposit on the cork can be the result of various reasons such as the age of the wine (which creates harmless tartrate crystals which adhere to the underside of the cork) or the use of an additive (a color adjunct has been added) or a lack of filtration (wine lees); these deposits can help us to think about the type of producers that are behind the wine.

So next time you open a bottle, don’t smell the closure but instead spend thirty seconds thinking about why the wine was closed with this particular closure and what that tells us about the producer. You can bet that many hours of debate and trials have led to the use of this specific closure.

Types of closure

Wine Closure: Natural cork

Appearance: 100% natural

Cost: Expensive

Best for: Long-aged reds


Wine Closure: Colmated Cork

Appearance: Gaps in cork filled with cork dust

Cost: Cheap

Best for: Entry level wines


Wine Closure: Agglomerate cork

Appearance: Particle of corks glued together

Cost: Cheap

Best for: Mid market wines


Wine Closure: One + One cork

Appearance: Agglomerate cork + disc of natural cork at the end

Cost: Moderate

Best for: Mid market wines


Wine Closure: Cork dust plus polymer

Appearance: Diam and look alike

Cost: Wide range

Best for: Mid market to upper market (Diam can be found in expensive bottles)


Wine Closure: Moulded plastic

Appearance: Solid piece (SupremeCorq)

Cost: Cheap

Best for: Entry level wines


Wine Closure: Extruded plastic

Appearance: Honeycomb inside (Normacorq)

Cost: Cheap

Best for: Entry level to mid market wines


Wine Closure: Screwcap with foam liner

Appearance: Liner inside the cap is foam like

Cost: Cheap

Best for: Entry level wines – reds in particular


Wine Closure: Screwcap with tin liner

Appearance: Liner inside the cap has a visible tin layer

Cost: Moderate

Best for: All wines


Wine Closure: Vinolok

Appearance: Glass or plexiglass T top

Cost: Expensive

Best for: High end wines but uncertain about ageability


Nicolas Quillé is a Master of Wine and so uses the accredited term 'MW' after his name. He is also Chief Winemaking and Operations Officer for the Crimson Wine Group.

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