Options for packaging and closures Flashcards
Oxygen management when packaging
Oxygen management is the most important consideration when bottling or filing other containers because the amount of oxygen in the bottle or container will determine the shelf life and expected development of the wine
The total package of oxygen in wine is the combination of:
- The amount of dissolved oxygen in the wine
- The oxygen in the head space (below the closure)
- The amount of oxygen in the cork or other closure
- The oxygen transmission rate (OTR) of the cork or closure
Because of the above, winemakers are paying attention to limiting oxygen uptake in filling bottles or containers for expanse flushing the head space with an inert gas before closing the bottle and also to the OTR rates of the closures chosen
Option for packaging (6)
In most markets glass bottles are still the preferred option for packaging
Some exceptions are:
Producer markets where inexpensive plastic containers are used to collect wine form a local winery for short term storage and early drinking (France)
The importance/popularity of bag-in-box in some market (Sweden)
The options for packaging are:
- Glass
- Plastic
- Bag-in-box
- Brick
- Pouch
- Can
Advantages of glass packaging
- Made of inert material, conveys no taint to the wine and is impermeable to oxygen
- Bottles can be delivered to wineries in a near sterile condition, having been shrink-wrapped when still hot (vacuum verpakt)
- Inexpensive to manufacture and comes in a range of colours
- 100% recyclable, although some closures are less so
- It remains the best option for aging wines as it is impermeable to oxygen
Disadvantage of glass packaging
- Initially it has a high carbon footprint because of the heat needed to manufacture it
- Heavy to transport, again contributing to its carbon footprint, especially if it’s transported for thousands of miles
- It’s fragile
- Glass bottles are rigid, once opened it’s subjected to rapid oxidation
- Wine packed in clear bottles can be spited by light strike from fluorescent (supermarkets) or natural light, producing sulfur related aromas, green or even better brown bottles give better protection
Bag-in-box
Consists of a cardboard box that houses a flexible bag inside, usually made of aluminum foil (which acts as a barrier to oxygen). Very successful in Australia and Sweden
Advantages:
- Flexible pour size (1.5-20 liters)
- Suitable for home and commercial use
- Easy to store
- Low environmental impact (recyclable)
Producers may use a high-quality tap as this is where most oxygen ingress occurs and the wine usually has slightly higher so2 levels than glass to counter oxidation
Shelf life is 6-9 months although the best protect the wine up till a year
Brick
Often referred to as a Tetra Pak, after the leading manufacturer, made of paper card with plastic layers and an aluminum foil layer that excludes oxygen and light
Can be entirely filled with wine, thereby excluding oxygen
Accepted by consumers at lower price points and does well in markets where price is a major driver (Germany)
Filling equipment is a big investment, the filling of bricks can be outsourced
Can
The ring pull can offers many advantages for wine consumed early;
- light weight
- robust
- easy to open
- impermeable to oxygen
- recyclable
Companies continue to experiment with cans which may prove attractive in the RTD markets (festivals uk/usa)
Filling equipment is a big investment and filling cans is generally outsourced
Plastic
PET:
- Form of plastic, 1/8th of the weight of glass
- Inexpensive and recyclable
- Rages in sizes, standard bottle size/RTD ready to drink
- Well suited for wines with a limited shelf life and for quick consumption and in informal setting (outdoor eating, travel)
Special filling equipment is required as the PET bottles are inflated at filling
Pouch
Are similar to bag in boxes and are available in different sizes (1.5 liter) and single serve
AH wild pig
Options for closures
The ideal closure would combine the following properties:
- Protect the wine from rapid oxidation
- Be inert so that it does not affect the quality of the wine adversely
- Be easy to remove and to re-isert
- Be cheap, recyclable and free from faults
Closure options are
- Natural cork
- Technical cork
- Synthetic closures
- Screwcap
- Glass stoppers
Natural cork
Continues to be the most popular closure, its light, flexible, inert (but can house harmful fungi) and comes from a renewable natural resource. It has a positive image in the eyes of the consumer and opening the bottle with a corkscrew is seen as part of they enjoyment of drinking wine
Cork is generally a good oxygen barrier, natural corks have variable rates of oxygen ingress. Therefore, the same wine ages at different rates in the medium to long term
TCA
Natural corks can taint wine by the creation of TCA (trichloranisole) resulting in a unpleasant smell of mould or wet cardboard that also suppresses the fruit character
Affects 3-5% of bottles closed with natural corks
Cork taint has led to two developments; the creation of alternative closure and efforts to reduce or eliminate the incidence of cork taint by the industry. Approached include:
- Cleaning corks with stream extraction
- Creation of technical corks, a closure from recomposed cork particles that have been cleaned and reconstituted with plastic
- More quilt control during production, including high tech solutions to check for the presence of TCA
- Introducing a barrier between the wine and the cork by placing an impermeable membrane between the cork and the wine, this excludes any aromas reaching the wine
Technical corks
Made by a manufacturing process
Agglomerated corks are the cheapest option, in which cork granules are glued together. Suitable for inexpensive wines intended to drink quickly after purchase
Another option is the one-plus-one cork, in which the largest part consist of inexpensive agglomerate, but is finished with a disc of natural cork at both ends.
Available in different oxygen-ingress rates, so the winemaker can choose a closure for wines to be drunk in short term or for aging
Synthetic closures
Known as plastic corks, made of food grade plastic with a silicone coating
Moulded closures are the cheapest, but are relatively rigidity which makes them more difficult to re-insert in the bottle. Extruded closures addressed this issue and are more elastic
Moulded closures offer limited oxygen protection and are therefore only suitable for wines for early consumption. Extruded closures now come in a range of oxygen-ingress rates
Some plastic closures cause a loss of flavour intensity because plastic absorbs some flavour molecules
Screwcap
Aluminum closure, rolled onto the outside of a bottleneck, specially designed for this purpose. It requires different closure equipment from in-bottle closures
An issue with screw caps, especially with almost impermeable thin linings, is that wines can become reductive after bottling, with an unpleasant onion like smell on the first opening. To avoid this issue, winemakers often add slightly lower so2 levels to the final wine
Its easy to open without any tool and it eliminates the possibility of taint from corks (TCA can still be picked up i.e. from infected barrels, but less likely)
There is a high degree of acceptance for quality wines from Australia and New Zealand, and for inexpensive wines from the USA. The winemaker should take this into account
