Circularity Without Compromising Performance: Engineering Solutions for Flexible Pet Food Packaging

Far from being competing objectives, circularity and performance can reinforce one another when packaging is analyzed as an integrated functional system, designed to meet specific technical requirements throughout the value chain, from packaging to final consumption.

Circularity Does Not Mean Substitution: It Is Redesign

When discussing circularity in flexible packaging, several strategies are often mentioned: downgauging, weight reduction, incorporation of recycled content, migration toward mono-material structures, implementation of more efficient processes, and waste reduction initiatives. While all of these are valuable tools, they are insufficient when applied in isolation.

Every component within a flexible package serves one or more specific technical functions. Consequently, any structural modification has technical implications that must be analyzed and addressed. The most common mistake is attempting to simplify a package without understanding why it was designed that way in the first place.

In the pet food segment, where products present unique challenges related to stability, logistics, and consumer use, this approach becomes particularly critical. Pet food—especially dry formulations with high fat content—is highly sensitive to oxidation, moisture uptake, and aroma loss, all of which directly impact the consumer's acceptance.

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The Starting Point: Understanding Packaging's Technical Function 

Every effective redesign begins with a deep understanding of the package's primary function. In pet food applications, packaging plays a fundamental role in preserving product quality, shelf life, and user experience.

Its key technical functions include:
 

Marketplace

Pouches

Doypacks

Films

Secondary PE packaging.

• Oxygen barrier: Essential for preventing fat oxidation and preserving palatability. 
   
• Water vapor barrier: Necessary to avoid caking, nutritional degradation, and microbial growth. 
   
• Mechanical resistance: Required to withstand impacts, stacking loads, and intensive logistics handling. 
   
• Seal integrity: Critical to ensuring hermetic protection throughout the product's shelf life. 
   
• Consumer functionality: Including controlled opening features and resealable systems that help reduce product waste. 

Packaging performance does not depend on a single material but rather on the balance among all of these functions. This is precisely where technological innovation plays a decisive role.

Product Protection: New Architectures for Long-Standing Challenges

Regarding barrier and product protection, advances in coextrusion technologies have enabled the development of polyethylene-based structures with enhanced functional properties that significantly reduce grease migration, oxygen transmission, and aroma exchange. These solutions rely on multilayer architectures in which different resins perform specific functions within the structure.

Incorporating barrier copolymers such as EVOH, even at relatively low concentrations, allows manufacturers to achieve protection levels comparable to those of traditional multi-material structures. Historically, materials, such as BOPET and BOPA, have been used to provide rigidity and barrier performance, but they require lamination with polyethylene to deliver sealability and mechanical strength. While technically effective, these combinations present significant challenges for recycling.

Multilayer polyethylene structures can now integrate barrier performance, mechanical strength, sealing properties, optical characteristics, and processability within a single system, advancing toward mono-material configurations that are more compatible with mechanical recycling streams and with the design-for-circularity guidelines increasingly adopted by global brands.

Likewise, the development of machine-direction orientation (MDO) processes applied to high-density polyethylene has created the potential to replace traditionally oriented films, such as BOPP, while maintaining adequate stiffness and further improving overall package circularity.

Mechanical Strength and Seal Integrity: Beyond Packaging Thickness 

When discussing sustainability, thickness reduction is often one of the first strategies considered. However, reducing gauge without redesigning the structure is a reliable recipe for failure. In pet food packaging, resistance to tearing, puncture, and deformation is critical to maintaining package integrity throughout its entire life cycle.

The phenomenon known as dimpling—the deformation of the package caused by kibble pressure, particularly in bags located at the bottom of a pallet—requires structures to absorb loads without compromising package integrity or seal performance. These stresses are not always replicated in standard laboratory tests, making it essential to consider real-world storage and distribution conditions.

This requires not only a robust film structure but also reliable seals to withstand demanding stacking, transportation, and handling environments. Furthermore, during storage and distribution, the friction coefficient of the outer surface becomes increasingly important for maintaining stable pallet loads and preventing slippage or pallet collapse.

Multilayer coextruded architectures allow functions to be redistributed among layers, incorporating engineered resins where needed, compensating for gauge reductions, and optimizing costs without sacrificing performance.

Functionality and Waste Reduction

Circularity extends beyond packaging materials—it also encompasses how consumers interact with the package. In this regard, controlled-opening and resealable closure systems play a key role in reducing food waste by helping preserve product quality after opening and extending shelf life in the home.

Today, a variety of front, perimeter, and traditional closure solutions are available, along with easy-open systems designed to enhance the consumer experience without compromising package integrity or recyclability. Integrating these features from the initial design stage, rather than adding them later, is essential for achieving the right balance between usability, technical performance, and sustainability.

Conclusion: Circularity as an Engineering Discipline

In this context, it is essential that packaging redesign decisions be made through a multidisciplinary approach. Industry experience consistently shows that the best results emerge when development, quality, production, procurement, and marketing teams work simultaneously, aligning technical, commercial, and environmental objectives from the earliest stages of a project.

It is equally important to validate proposed changes through technical testing and real-world performance evaluations. Barrier testing, sealability assessments, mechanical resistance analysis, pallet stability studies, and distribution performance trials anticipate deviations and refine designs before industrial implementation. This preventive approach reduces operational risks and avoids unnecessary costs.

Advancing toward more circular packaging solutions in the pet food industry is neither a trend nor a marketing exercise. Above all, it is a technical challenge that requires expertise, sound judgment, and a systemic understanding of packaging. When redesign is approached through engineering—analyzing functions, interactions, and consequences—it becomes possible to develop solutions that effectively protect products, meet logistical requirements, and align with the principles of the circular economy.

The good news is that the necessary technological tools already exist. The real differentiator lies in how they are applied.

By Pablo Petinatto, Petropack
Source: All Pet Food Magazine