Mobile-Menu

Green protection Bioplastic protects food under protective gas

Source: FNR | Translated by AI 2 min Reading Time

Related Vendor

FAULHABER Drive Systems

Researchers have now developed a prototype of an almost completely bio-based, thermoformable multilayer film for packaging food under protective gas.

Such plastic trays are commonly known as packaging for minced meat. Now, a team of researchers has managed to develop viable ones made from bio-based PLA. Smart ideas also make the material strong as a barrier against oxygen and water vapor.(Image: Lid fox)
Such plastic trays are commonly known as packaging for minced meat. Now, a team of researchers has managed to develop viable ones made from bio-based PLA. Smart ideas also make the material strong as a barrier against oxygen and water vapor.
(Image: Lid fox)

The Fraunhofer Institute for Process Engineering and Packaging (IVV) and Albstadt-Sigmaringen University have developed a plastic film based on PLA (polylactide), soy protein, and sunflower wax within the framework of the "PLA4MAP" project. Its good barrier properties are emphasized as being special. This is because sensitive foods such as fresh meat or sliced sausage and cheese products are often packaged under a protective gas atmosphere to inhibit germ growth and extend shelf life. To maintain the modified atmosphere for a sufficiently long time, the packaging materials must have certain gas barriers. Many bio-based plastics available on the market do not yet possess these properties. This is where the PLA4MAP project comes in.

The structure of the film is as follows

The researchers developed a tray made from a 4-layer composite material. A thin protein layer of soy protein concentrate as an oxygen barrier and a thin wax hot-melt layer as a water vapor barrier were placed between two PLA cover layers, as explained in more detail. For the wax layer, the choice fell on sunflower seed wax because it is a by-product of edible oil production. The sealing film was also based on PLA but enhanced with metallization. Transparent barriers with silicon or aluminum oxide layers are also conceivable.

With suitable methods, recycling is possible

The composite material therefore fulfills all the required barrier properties, can be very well processed by thermoforming, and has a very high bio-based content. Only the inorganic layer of the lid film and portions of the wax hot-melt layer are not of plant origin. The PLA content in the multilayer composite is just under 82 percent. If suitable sorting and recycling streams for PLA are established, this portion could be recycled. Trials in the project showed that new, functional packaging can be produced from the recycled material. Currently, PLA is only used for energy recovery in Germany with an estimated total market share of less than one percent in plastic food packaging.

There are still hurdles in PLA production

The high energy consumption in PLA production and the processing process, which has so far only existed on a pilot scale, have meant that the sustainability of the new bio-based composite material does not yet match comparable fossil-based packaging materials. However, there is still significant potential for optimization in both areas. According to experts, the currently still high production costs can also be reduced by expanding global PLA production and especially by reducing the weight of the packaging.

Subscribe to the newsletter now

Don't Miss out on Our Best Content

By clicking on „Subscribe to Newsletter“ I agree to the processing and use of my data according to the consent form (please expand for details) and accept the Terms of Use. For more information, please see our Privacy Policy. The consent declaration relates, among other things, to the sending of editorial newsletters by email and to data matching for marketing purposes with selected advertising partners (e.g., LinkedIn, Google, Meta)

Unfold for details of your consent

Related content