From: Packaging News

Food packaging supplier Krehalon and Dunbia have created a single-polymer protein packaging for Co-op to meet the retailer’s ‘80% easy to recycle by 2020’ ambition.

The current format of choice for modified atmosphere protein packaging traditionally uses polythene (PE) sealing mechanisms to enable secure seal of the film lid to the amorphous polyethylene terephthalate (APET) – most common hard plastic used for food stuffs. This is a complex multi-material structure which makes protein packs more difficult to readily recycle.

The key focus of the Dunbia-Krehalon partnership was to help simplify Co-op’s packaging for minced beef to one polymer type and help increase recycling at consumer level.
As a result, Krehalon-Dunbia developed a mono-APET pack structure using a specialist top web film which enabled the removal of the PE sealant layer and achieved a strong fused seal to the mono-APET base.

The new mono-material alternative offers more environmental benefits without compromising seal strength, food safety, pack integrity and product shelf life. The unique high barrier top film also includes anti-fog properties for optimum pack clarity and visual appeal.
“Sealing to a mono APET layer, unsupported by a PE sealant layer, was a challenging project as it required for us to come up with a radical alternative to PE sealing echanisms whilst maintaining strong hermetically sealed packs.

“After months of development work, however, involving shelf life, transit and store trials, the move to a mono-based pack was made possible by using our specialist top web film with advanced sealing technology,” said a Krehalon spokesperson.

Dunbia was able to use its current manufacturing equipment without any modifications and experience no reduction in production output or machine efficiencies from switching to the new format.

The success of this packaging development demonstrates that film technology is now available for retailers to consider the removal of PE in their pre-formed trays or thermoformed pack formats to simplify their recycling chain whilst offering tight hermetically sealed packs equivalent to the strength of a PE-to-PE bond but with improved clarity and visual pack appearance.

“The Mono-APET project has been a great step forward in our ambition to make all of our packaging easy to recycle. By simplifying the plastic trays used for protein to just one polymer type, we have been able to make Co-op branded packaging more attractive to recyclers and, therefore, more likely to be recycled,” said Rob Thompson, packaging technologist at the Co-op.

Enabling the use of a mono base web not only makes protein packaging easier to recycle but also has the potential to reduce pack costs due to the potential downgauging that could be achieved from the removal of the PE sealant layer. In short, the same pack quality can be achieved at a reduced total pack weight and causing less harm to the environment.
Future opportunities within this project include the ability to fully sandwich print the top film to remove the need of labels (or other added surface decoration) offering even further environmental and cost benefits.

Moreover, when sealed to CPET structures, the film is also approved for “direct to oven” applications (200 degrees for 2 hours) offering additional convenience.