What are the benefits if we recombine cellulose materials and their performances?

Some tests and trials to fine-tune solutions with basic barrier performances in line with the goal of composability.

The shelf life of food products and cellulose fibers has always been considered a challenging combination, if not impossible, unless a collaboration with other materials is initiated.

How can we design a successful path to face the challenge, aiming to have eco-friendly solutions, particularly compostable ones, while prioritizing the cellulose component?

This was discussed by Giorgio Mariani, product manager of the Eco & Food division at LIC Packaging, specializing in paperboard solutions for logistics, display, and promotion of fast-moving consumer goods in modern retail channels through primary, secondary, and tertiary packaging.

Whether it’s fruits and vegetables, cured meats and cheeses, or portioned meat and fish, the user establishes a series of priorities: cooking and consumption? Recyclability? Compostability? Protection?

There are no one-size-fits-all answers to a multitude of problems, but there is the possibility of using converting technologies for cellulose materials and combining them to approach eco-compatibility goals.

Integrating Different Materials

For example, LIC Packaging has integrated various materials: the cellulose-based support for trays used for muffin batter baking consists of non-stick paper for cooking in contact with the product, kraft corrugated vegetable fiber made from virgin pulp, and an anti-grease paper on the outside to prevent the passage of greasy components. With this composite material, thermoformable support was created with a primitive barrier effect highly appreciated in baking, which allows water vapor to pass through, unlike trays made of aluminum or other materials combined with plasticizers.

This “custom” solution has been successfully tested for industrial compostability according to EN 13432 standards.

Working on Waves

Another area explored to develop barrier solutions in the future is the wave structure. The G-wave, today, refers to thicknesses of 700 microns, but LIC Packaging has developed a 700-micron support with a weight lower than market standards: 250 g per m² if made from virgin fiber, and 285 g per m² if made from recycled fiber, while competitors are unable to go below 350 g per m². To differentiate it, this material has been branded as HT Board.

In response to the need for solutions for baking vegetables, there were requests for packaging that could be stored in the fridge for 3-4 days and then be used in either a microwave or traditional oven without altering or leaching the cellulose material. The reference paradigm during the research and development phase was to use stiff boards weighing between 180 and 600 g, and a solution was developed with equal longitudinal and transverse rigidity, thanks to the micro-fluting, which allowed it to compete with trays made from stiff paperboard between 500 and 600 g.

The new material weighs only 300 g, with 45% less material compared to the trays made from stiff paperboard. In this case, the advantage lies not in barrier effects but in the prevention of packaging waste, thanks to a significant reduction in material use.

Combining Bioplastics

Returning to the performance of “sealability,” while the prototypes developed exhibited excellent grease-resistant properties, the deficit was in moisture retention. Thanks to the collaboration with suppliers of supports and thermoforming and gluing machines, it was possible to create trays capable of holding the moisture component of food by combining them with a compostable bioplastic material.

New Materials: Grass Paper Packaging

Another area to consider carefully is the use of grass paper packaging solutions. This involves adding hay fibers to the paper pulp, which helps reduce CO2 emissions by 75%, lowers water consumption to just 2 liters per ton (compared to the 5,000 liters/ton used for wood pulp), reduces energy consumption by 90%, and eliminates the use of chemicals.

An Unconventional Point of View

While tests and research are being conducted by combining different materials with the goal of compostability and pursuing barrier effects, it is also interesting to explore completely different paths: instead of pursuing the goal of a 90-day shelf life, what constraints and consequences would arise from a different scenario?

Is it possible to imagine a product class that openly declares freshness and fast consumption, along with the nutritional and organoleptic benefits associated with this status?

In this perspective, is it more important to focus on packaging or logistics?

The provocative question is whether we really need products with such long shelf lives: what is the environmental cost?

Can we imagine letting the consumer choose between two products in front of the same refrigerated display, where one claims, “consume within 5 days”?

Some paradoxes are not so far off: there are already packaging materials today that cost more per kilogram than the food contained inside.

Article published in Com.Pack magazine, Issue 37, 2019.