15.5 Packaging and Closures

Question 1

What considerations are taken into account when choosing packaging and closures?

Answer 1

1. intended for early consumption, or has potential to age
2. the markets in which it will be sold
3. oxygen management

Question 2

What is the most important consideration when choose packaging and closures? Why?

Answer 2

• oxygen management
• the amount of oxygen in the final container will determine the shelf life and expected development of the wine
  leads to
• premature browning and oxidised characters (loss of fruit, development of off-flavours including bruised apple)
  too little leads to
• may lead to reductive characters (e.g. onion, rotten eggs)

Question 3

What comprises the total package oxygen of a wine? What is the greatest contributer?

Answer 3

1. the amount of dissolved oxygen in the wine
2. the oxygen in the head space (below the cork or other closure) – usually the greatest contributor
3. the amount of oxygen in the cork or other closure
4. the oxygen transmission rate (OTR) of the cork or closure.

Question 4

What are the 2 main alternatives to glass bottles? Where are these popular?

Answer 4

1. Plastic
 inexpensive plastic (PVC) containers  for short term storage and early drinking

2. bag-in-box
   in some markets (50 per cent and more), such as the Swedish market.

Question 5

Glass

Answer 5

most popular globally
Glass bottles finished with cork
advantages
1. made of inert material that conveys no taint to the wine, impermeable to oxygen
2. delivered to wineries in a near sterile condition, having been shrink-wrapped when still hot
3. inexpensive to manufacture, comes in a range of colours.
4. 100% recyclable (some colours are less easy to recycle)
5. best option for the ageing of wine as it is impermeable to oxygen
Disadvantages
1. high carbon footprint initially because of the heat needed to manufacture it
2. heavy to transport, contributing to carbon footprint, especially if it is transported far
3. fairly fragile
4. rigid; once opened, subject to rapid oxidation
5. clear bottles susceptible to light spoilage (light strike) producing sulfur-related off-aromas
brown and green are best

Question 6

Plastic (PET)

ADv and Disadv?

Answer 6

Disadv
- must be lined with a barrier to oxygen if it is to be impermeable and therefore give a reasonable shelf life

• special filling equipment required as the PET bottles are inflated at filling

Adv

• lightweight plastic (~1/8th the weight of glass)
• tough
• inexpensive
• recyclable
• range of sizes (standard bottle, single serve)

Question 7

For what types of wines is polyethylene terephthalate well suited?
Describe bag-in-box packaging.

What is the shelf life of bag-in-box wine?

Where is bag-in-box wine popular?

Answer 7

• wines with a limited shelf life, early consumption, informal setting, planes (breakage is a hazard)
• consists of a cardboard box that houses a flexible bag inside
• bag usually made of a very thin aluminium foil (which acts as a barrier to oxygen) covered on both sides by a suitable plastic
• OR bag is made from a plastic that gives some protection from oxygen and is resistant to cracking

adv

1. flexible pour size (one or more glasses)
2. good protection from oxygen after wine has been poured (the bag collapses inside the box)
3. a range of sizes, 1.5–20 litres, suitable for home and commercial use
4. easy to store
5. low environmental impact (light to transport, can be recycled)

Important must-haves
Higher so2 needed to counter oxidation
- a low dissolved oxygen level
- no head space
- low carbon dioxide (the last to avoid the bag bulging)

Shelf life

• 6–9 months depending on the quality of the manufacture
• the best may protect wine for up to a year

Pop in

• Australia, where it was pioneered
• Sweden

Question 8

Describe ‘brick’ packaging. What name does this packaging go by?

Where is brick packaging common?

What are the costs associated with brick packaging?

Answer 8

• aka ‘Tetra Pak’
• made of paper card with plastic layers and an aluminium foil layer that excludes oxygen and light
• can be entirely filled with wine, thereby excluding oxygen
• does well at lower price points
• does well in markets where price is a major driver (e.g. Germany)
• filling equipment is a big investment
• some producers outsource the filling of bricks

Question 9

Describe ‘pouch’ packaging.

Answer 9

• similar to the bags inside bag-in-boxes

- available in larger (e.g. 1.5 litre) and single serve sizes

Question 10

What are the advantages of ‘can’ packaging?

Answer 10

• light weight
• robust
• easy to open
• impermeable to oxygen
• recyclable

Question 11

What has to be done to cans before packaging?
What are the costs associated with can packaging?
For what types of wine is can packaging used?

Answer 11

The aluminium has to be lined with a plastic to avoid being attacked by the acidity of the wine

• filling equipment is a big investment
• some producers outsource the filling of cans

For wine that is to be consumed early

Question 12

The ideal closure would combine what 4 properties?

What are the 5 main closures?

Answer 12

1. protect the wine from rapid oxidation
2. be inert so that it does not affect the quality of the wine adversely
3. be easy to remove and to re-insert
4. be cheap, recyclable and free from faults
5. Natural cork
6. Technical cork
7. Synthetic closure
8. Screwcap
9. Glass stoppers

Question 13

What is the most common closure?

What percentage of wine bottles use cork as a closure?

Answer 13

Cork

60% of wine bottles are closed with cork

Advantage
light, flexible. inert. comes from a renewable, natural resource
Some corks have been adapted for inexp wines, they are shorter, lower grade

Disadv
can taint wine through the creation of TCA
has variable rates of oxygen ingress means same wine ages diff per bottle

Question 14

What has the incidence of cork taint lead to?

Answer 14

3-5% bottles affected by taint

1. the creation of alternative closures
2. cleaning corks with stream extraction
3. creating closures from recomposed cork particles that have been cleaned and reconstituted with a plastic
4. more rigorous quality control during cork production, including high-cost high-tech solutions
5. introducing a barrier between the cork and the wine; this is an impermeable membrane between the cork and the wine that gives a wrinkled appearance on the end of the cork and excludes any aromas reaching the wine

Question 15

What is the largest word producer of cork products? What method of cork taint protect have they championed?
Name another cork producer. What method of cork taint protect have they championed?

Answer 15

• Amorim
• cleaning corks with stream extraction
• Diam
• creating closures from recomposed cork particles that have been cleaned and reconstituted with a plastic

Question 16

What are technical corks?

What is the cheapest type of technical cork? For what types of wines are these corks suitable?

Name 2 types of technical corks.

Answer 16

Made from cork that has been subjected to a manufacturing process

• agglomerated cork in which cork granules are glued together
• suitable for inexpensive wines intended to be drunk quickly after purchase

1. agglomerated cork
   the largest, central, section is inexpensive agglomerate, but it is finished with a disc of natural cork at both ends
2. one-plus-one cork

fleyible because
They are available with different oxygen-ingress rates so that a winemaker can choose a closure for wines to be drunk in the short term or for ageing.

Question 17

What are synthetic closures?

Answer 17

• aka ‘plastic corks’
• synthetic closures are made of food-grade plastic with a silicone coating

moulded closures

• type of synthetic closure
• cheapest
• relative rigidity makes them more difficult to re-insert in the bottle

extruded closure

• type of synthetic closure
• more elastic
• made by an external firm layer of plastic covering a plastic foam

Disadv
- offer limited protection from oxygen ingress
- only suitable for wines for consumption within months
Adv
- now come in a range of oxygen-ingress rates
- leading producer Nomacorc
- claims that its top line is suitable for extended ageing in bottle

Question 18

What is a main disadvantage of all synthetic closures?

Answer 18

• flavour scalping: the loss of some flavour intensity because plastic absorbs some flavour molecules

Question 19

What is a screwcap?

For screwcaps, what materials are used to seal the wine? What are the advantages of each?

What is the main issue with screwcaps?

How do winemakers avoid reduction when bottling with screwcaps?

What are the main advantages, from a consumer standpoint, of screwcraps?

Answer 19

• an aluminium closure rolled onto the outside of a bottleneck that has been specially designed for this purpose
• requires different closure equipment from in-bottle closures

1. Tin (impermeable to oxygen)
2. Saran (a form of plastic with low permeability to oxygen, better known for its use as cling film)

Wines can become reductive after bottling, with an unpleasant onion-like smell on first opening

Adapting the final wine to have slightly lower SO2 levels

• can be opened without a special tool
• eliminate the possibility of taint from corks

accepted
Australia, New Zealand, UK
not accepted
usa

Question 20

What is a glass stopper?

Answer 20

• aka Vinolok
• a closure made from glass, but where the actual seal is formed by a plastic ring
• Wine can be stored for similar lengths of time as under other current closures (e.g. natural cork)
• Look attractive
• Special bottles must be used to ensure a perfect fit
• As expensive as top quality cork
• Only suitable for premium and super-premium wines
• Super expensiv