Amcor's decision to produce the PET bottle for customers in Australia and New Zealand provides a major boost to Constar's bid to market its oxygen-scavenging packaging to a wider range of drink makers. Amcor is one of the world's largest packaging companies, with annual sales of about €6.5bn and 217 plants located in 34 countries.
Philadelphia-based Constar has developed materials that when blended with PET, binds oxygen, thus preventing the degradation of products such as juices, teas and flavoured water.
Amcor will use Constar's Oxbar PET, a multi-layer oxygen scavenger. Constar says its Oxbar product can also protect oxygen-sensitive products such as beer, fruit-based beverages and foods in PET containers.
While the use of PET is one of the fastest growing sectors of the beverage bottling market, taking over from glass and cans as the container of choice, its use has been mainly limited to fizzy drinks and water.
PET has the practical benefit of being lightweight, shatterproof and recloseable. It is also completely recyclable, giving it an edge under the EU's new regulations on reducing packaging waste.
However PET, and plastic in general, is not very good at keeping oxygen from permeating the container and reducing the shelf life of such products as juices, teas and flavoured water. Oxygen has a degrading effect on flavour, colour and vitamin content for many beverages.
Constar has also developed MonOxbar, a monolayer version of Oxbar that also costs less to produce. The company has also developed a clear material called DiamondClear, that when blended with monolayer PET, binds oxygen.
Many oxygen scavenging products on the market need multiple layers to keep the gas from entering the bottle, thus reducing the plastic's transparency.