In the US and UK biodegradable food packaging is making the news once again as major retailers Sainsbury's and Wal-mart both launch their own lines.
Both product lines - at Sainsbury's UK its food tray packaging, in Wal-Mart US it is a line of disposable plates and cups - are produced by Eastman Chemical of Tennessee, US, from biodegradable copolymer.
Although it was Sainsbury's packaging provider that undertook the new packaging, the innovation itself was driven by Sainsbury's, one of the UK's most progressive supermarket chains with respect to environmental concerns.
"We have lead suppliers with whom we work very closely on new technology trials," said Terry Robins, technical manager of Sainsbury's packaging division. "In this case, we worked with one of these lead suppliers to make sure the biodegradable trays would work in our system. Then we made it known to all our organic produce suppliers that we'd prefer this tray."
Compared to US retailers, UK retailers have a much bigger say in what packaging materials are specified because the nature of the supply chain is much more hierarchical.
The Apack trays consist of natural products, including starch mixed with limestone and fibres in a slurry. This mix of materials is formed into moulds and dried. Sheets of formed trays are discharged immediately into a vacuum laminating system that uses an organic adhesive to bond a layer of 2.5-mil Eastar Bio copolymer to the food-contact side of the formed trays.
Apack guarantees that 99.7 per cent of the tray will biodegrade in a compost pile, commercial or domestic, within six weeks.
Sainsbury's stated that initially the packaging will only be used for organic food purposes because of the costs involved in producing it and that customers buying organic foods are also interested in environmentally friendly packaging.