Closures Flashcards
(8 cards)
Closure definition
A wine closure seals the wine in the package and prevents oxidation without imparting character into the wine.
Key Considerations
- TCA (or other taints)
- Ease of application and removal
- Tamper resistance
- Oxygen transmission rate
- Cost relative to wine quality
- Expected aging potential of wine
Topic specific vocabulary:
TCA
Super-critical CO2
Flavour scalping
- TCA - 2,4,6 Trichloroanisole produced as a result of mould. Detection at 2ng/L and recognition at 6ng/L (ETS). 5-8% of wine under natural cork has this defect (AWRI technical review #248)
- Super-critical CO2- Carbon dioxide in its supercritical state (between liquid and gas) exhibits unique properties that make it an effective solvent for cleaning cork.
-Flavour scalping - The absorption of flavour out of the wine
Natural cork
Outline
Punched from the trees of Quercus subers (oaks) after 25y, harvested every 9 years
Cost ($/ea) .65-1.3
OTR (mg/yr) < 0.1–283
Pros
* Excellent “breathability”
* Comes in different quality (and price) levels as well as lengths, with longer ones available for age-worthy wines and wider ones for larger format wines
* Relatively good insertion and extraction of the cork
* Offers the romance of the cork “pop”
* Allows for the preservation of cork forests and rural jobs in small villages
* Ensures that the cork forests continue to offer homes for Iberian lynx, Iberian imperial eagles and Barbary deer, among other wildlife. World Wildlife Federation notes that cork forests are among the few examples on globe where human activity benefits the landscape.
* Recyclable
cons
* A potential harbor for the extremely unpleasant 2,4,6-trichloroanosole (TCA) compound that taints wine, making it “corked”
* Hard to get the best corks between the long line of producers and the considerable price they command
* Consistency cannot be guaranteed with the same degree of certainty as alternatives because it is a natural product
* Lubricants like silicon and paraffin can improve extractability – which sommeliers appreciate in the theater of restaurant dining rooms, but which can also cause oxygen ingress
* Random oxidation of bottles, particularly problematic for age-worthy white wines
Micro-agg or technical corks
Cork particles that have been treated and then compacted and glued together with a type of polymer
Cost ($/ea) .25-0.8
OTR (mg/yr) <~0.5
Pros
* Can chose desired – and guaranteed rates of breathability, in high end ranges like DIAM and Amorim Neutrocork-Premium
* The very best lines guarantee they are TCA and fault-free
* Retains the romance of the cork “pop”
* Helps keep the cork forests cultivated and preserves the homes of indigenous wildlife
* Recyclable
Cons
* Low-end and mid-range options could be TCA affected
* Also known as “agglomerates” because the corks are composed of tiny cork particles glued together. Highly sensitive sniffers can smell the glue.
* Some technical corks, especially with those that have a solid disk(s) of natural cork glued on one or both ends, can look cheap
* Sometimes not easy to use to recork bottle
Screwcap
A metal (usually aluminium) sleeve that screws on to the threads on a bottle and seals onto the lip of the bottle with a liner - Saran tin or saranex
Cost ($/ea) 0.1-0.15
OTR (mg/yr) <0.1 for tin, saranex 0.5
PROS
*Zero cork-induced TCA stink
*Easy to open and close
*Can brand just like you would a capsule and cork
*Smooth-sided cap options hide threads, creating a more polished look
*Don’t need to store wine on its side
*Doesn’t deteriorate like natural cork
*Can chose breathability of cap liners to optimize drinking windows
*Has shown to be an age-worthy wine closure on both red and white wines
*Tamper-evident fitments help prevent counterfeiting, as with Roll On Pilfer Proof (ROPP) aluminum closures
*Recyclable if liner is removed
CONS
*larger headspace and no vacuum means there can be increases in total package oxygen
*Reduction, or the tamping down of aromas, is very common
*Flute-shaped (deeply sloped, like Riesling) wine bottles more easily incur dents on the capsule closure, possibly causing the liner seal to pop and resulting in an oxidized wine
*perceived as cheaper in some markets eg USA and China
Synthetic
Usually has an outer liner and an inner filler. Can be moulded (domed ends) or extruded (plastic pipe filled with foam) usually polyethylene but can be
Cost ($/ea) 0.47-0.63
OTR (mg/yr) ~0.6
PROS
*Very good precision of material density and performance enabling efficient insertion
*Come in a wide variety of densities and prices
*Recyclable depending on material
*Like natural and technical corks, can be printed on
*Uniquely, can be ordered in a wide range of colors
*Can be chamfered, or tapered, for easy re-insertion into bottles
*TCA free
CONS
*Wine aroma scalping can also occur, where the synthetic material extracts aromas from the wine
*Must have correct wine style, expected time prior to consumption and stock rotation for synthetic used
*Partially or entirely a petroleum product that can vary in price and is non-renewable
*Corks that are not chamfered are hard to use to recork bottles
eg Mullan Road Cellars
Glass stopper
Vinoseal or vinolok, plastic o-ring between the bottle and the glass stopper
Cost ($/ea)
OTR (mg/yr) similar to natural cork but less variable
PROS
*TCA-free
*Easy to open
*Elegant look
*Reusable glass stopper – on the same or on another bottle
*Recyclable if seal is removed
*Wines develop more slowly due to little oxygen transfer
*Wide array of sizes for different bottle neck sizes
*Comes in different colors and frosted versions
CONS
*Like screw caps, makes wines prone to reduction, which flattens aromatic intensity
*Actual seal is a plastic gasket which can degrade and pinch allowing oxygen ingress
*Heavier than other closure alternatives, adding to carbon emissions
eg: schloss vollrads
