As far as growth is concerned, the packaging industry has nothing to worry about. Sustainability, however, is another story. And while the need for greener packaging represents a significant market opportunity, solutions that deliver the requisite performance at a competitive price are still thin on the ground.

A dominant technology in the packaging market is thermoforming, yet although, for example, bio-based trays have been around for a number of years, in general, they fail to meet the barrier properties required for sensitive food products.

Now, research institute IRIS, located in Barcelona, Spain, has announced the kick-off of a new European research project aimed at addressing this problem. Called ThermoWhey, the focus is to develop a new bio-based thermoformable barrier coating solution that can be used throughout the breadth of the packaging sector. This 28-month R&D project, which is funded by the EU Seventh Framework Programme (under the Manunet programme), will deliver a whey protein coating with improved thermoformability even after storage, while maintaining excellent barrier properties.

It's not the first time whey has been used to create a novel barrier coating. A previous project, called Wheylayer, has already yielded a patented whey-based technology that is currently on the fast track to commercialization. According to the researchers at IRIS, during the course of the Wheylayer development, it was found that the material was limited in terms of the deformation it was able to withstand during the thermoforming process after a storage time over a few days.

"Thermowhey will solve this issue so the material can be formed into cups and trays in a stable way after its production," said Carlota Feliu, marketing manage at IRIS. "Some chemical modifications are being done to the protein-based coating mixture to allow reaching a greater flexibility needed for the target process as well as its stability over time," she explained.

Overall, bio-based plastics still represent a niche but, thanks to technical innovations and with a 25% annual growth, have increasing potential to replace their synthetic counterparts. Unlike the group of biopolymers based on feedstock originating from edible crops, ThermoWhey represents a unique market offering that is derived from an agrofood by-product, that is able to deliver sufficient barrier properties for products packed in modified atmosphere (MAP). The project will develop a complete manufacturing set up and optimized process for producing whey powder (WPC), agglomeration process for whey protein based barrier coatings, as well as a coating process for films, and the manufacture of thermoformed packaging (blisters and trays) for pharmaceutical and food industries. The aim: to solve the multiple challenges of finding a new commercial use for a currently discarded cheese by-product and replacing petroleum-based plastics with 100% natural biopolymers that are able to be recycled without in any way compromising performance.

Already, the project is progressing well, according to IRIS. The objective is to have a market-ready coating available at the end of the 28 months of the project. The project has also budgeted time for the optimization of the thermoforming process and the production and validation of demonstrator samples of trays.

"This means that the formulation is likely to be ready even earlier than the end of the project," reported an optimistic Feliu.

The consortium for this project is complementary, combining the expertise of 4 SMEs, partners (IRIS coordinator, GEBA, MLANG and SERVIPLAST) and one research institute (FRAUNHOFER) and brings together competences from Spain and Germany.