SIG’s alu-free cartons unraveled: Full barrier launch incorporates oxygen-sensitive products

20 Jan 2022 --- SIG has launched the world’s first aluminum-free full barrier packaging materials for aseptic carton packs, suitable for oxygen-sensitive products like fruit juices, nectars, flavored milk or plant-based beverages. 

Signature Evo extends SIG’s lower-carbon offering, after the aseptic systems and solutions provider previously developed aluminum-free materials for oxygen-insensitive products like plain white UHT milk.

The new packaging materials are expected to achieve a similar carbon footprint reduction to combibloc EcoPlus. The carbon reductions will be confirmed through an independent, critically-reviewed life cycle assessment.

Like all SIG packs, Signature Evo is fully recyclable in existing recycling streams. The materials will initially be launched in the combiblocMini portion-sized format before being extended to other formats.

PackagingInsights sits down with Sina Gerlach, SIG’s sustainability marketing manager, who explores the challenges of developing aluminum-free carton packs for oxygen-sensitive products.

Full barrier protection
Gerlach says the main challenge in developing Signature Evo was creating an alternative to the aluminum foil barrier layer – used in SIG’s standard aseptic carton packs – that offers comparable protection for both oxygen-sensitive and insensitive products.

“Signature Evo is the result of cutting-edge innovation work by our R&D department in collaboration with our suppliers. We were also able to use our experience from developing combibloc EcoPlus, the first aluminum-free solutions for aseptic carton packs, for use with oxygen insensitive products only, which we launched in 2010.”SIG’s Signature Evo is designed for oxygen-sensitive products like fruit juices.

Like all SIG beverage cartons, Signature Evo is mainly made from renewable materials. The main component is liquid paperboard from FSC-certified and other controlled sources, which makes up approximately 70% of the structure by weight.

“The remaining 30% of the structure are polymers, based on values for combiblocMini 250 ml (specifications will change based on format, volume, and final board),” continues Gerlach.

“Signature Evo uses an alu-free barrier enhanced by a coated polyolefin film that blocks oxygen, aroma and water vapor. The paperboard together with a pigmented PE layer serves as a barrier to light.”

With barrier properties comparable to standard aseptic cartons that include an aluminum foil barrier layer, the new packaging materials ensure even oxygen-sensitive products are protected over long periods without the need for refrigeration.

Past and future steps
SIG led the industry with the first-ever aluminum-free solutions for aseptic cartons. By eliminating the need for an aluminum foil barrier layer, combibloc EcoPlus cut the carbon footprint of SIG’s standard packaging material by 27%.

Signature 100 cut carbon footprint further in 2017, offering a 58% lower footprint than SIG’s standard packaging material by linking the polymers to 100% renewable forest-based materials via a certified mass-balance system.

“In the future, Signature Evo will also be available in more options such as Signature Evo 100 – SIG’s full barrier solution for aseptic carton packs linked to 100% renewable forest-based materials – including all plastics,” says Gerlach.

SIG has sold more than 1.9 billion aluminum-free packs, providing long-life packaging solutions for liquid dairy products.Signature Evo’s carbon reductions will be confirmed by a life cycle assessment.

Way Beyond Good
Signature Evo marks the latest progress in SIG’s Way Beyond Good initiative, a “corporate compass” that targets using only raw materials from certified responsible sources and 50% of total source spend on net positive suppliers by 2030. 

Meanwhile, all SIG packs are fully recyclable in existing recycling streams. “The recyclability is in alignment with renowned design for recycling guidelines, for example, issued by organizations such as ACE, 4EverGreen, Ceflex and the Consumer Goods Forum,” adds Gerlach.

“By removing aluminum and using only polymers from the polyolefin family, Signature Evo is an innovation step on the journey toward using mono-materials and further simplifying the aseptic carton structure.”

Last year, SIG launched the “world’s fastest” family-size carton filler and packs for busy lifestyles and transformed a Brazilian dairy producer’s logistics with a QR-powered traceability system.

We recently spoke in-depth with Anna Rabanus, global category manager at SIG, about COVID-19’s impacts on on-the-go consumption habits.

By Joshua Poole