Solution-based plastic barrier packaging technologies are being developed in an environment of increasing global legislation directives and regulatory trends.

The annual Packaging Conference — just held Feb. 5-7 in Orlando, Florida — highlighted a strong focus on new business and emerging technology in the plastics packaging industry. Let's take a look at some key regulatory trends and highlight a recent emerging barrier packaging technology discussed at the event.

Regulatory trends

The system for regulating food contact materials and food packaging in the United States is fairly well established, although it has evolved over the years in response to certain lessons learned.

Pursuant to the 1958 Food Additives Amendment to the Federal Food, Drug, and Cosmetic Act, all substances that are intended to become components of food must receive premarket clearance from the Food and Drug Administration (FDA) unless they are subject to a specific exemption. The FDA supported the 1998 amendment of the Federal Food, Drug, and Cosmetic Act to provide for the submission of Food Contact Notifications (FCNs) in lieu of food additive petitions for food contact substances.

In the European Union (EU), efforts to harmonize the various systems in place at the national level in the individual EU member states continue, through several important pieces of legislation, including the Framework Regulation applicable to all types of food contact materials, as well as the Plastics Regulation applicable to food contact plastic materials and articles. In many other jurisdictions around the world, including South America, China, Japan and South Korea, just to name a few examples, food contact regulatory systems are still evolving.

The authorities in several jurisdictions, notably the United States and the European Union, are taking a closer look at how they regulate materials used in contact with foods and beverages consumed by sensitive populations.

The U.S. FDA has begun to use adjusted body weights and food consumption values when determining infant exposure to food contact materials. Accordingly, the FDA has started to regularly impose limitations on food contact materials for use with infant food, ingredients and breast milk, unless those uses are specifically addressed in an FCN submission.

Over the last few decades, more and more attacks have been made on chemical substances, calling them inherently harmful to human health and the environment. Concerns in this area have been fueled by the news media, which often sensationalize a single study indicating that there may be a problem with a particular chemical, even when other studies generate conflicting results.

These attacks on chemical substances have extended to ones used in food packaging. Bisphenol A (BPA) — a monomer used in making polycarbonate containers, can enamels and in other products where a stable polymer or modified coating composition is required — is a prime example.

As environmental awareness continues to grow, food manufacturers are under a greater degree of pressure to expand the use of recycled materials in food packaging. Regulations exist in some jurisdictions around the world specifically addressing the safety of recycling processes and materials, and we likely will see more of these types of regulations in the future.

Ultimately, however, food and food packaging manufacturers are responsible for ensuring that food packages comply with applicable regulatory requirements and are of a suitable purity for their intended use.

Plastic food packaging applications. (Image: The Packaging Conference)

Emerging technology

Let's highlight a recent emerging noteworthy plastic barrier packaging technology that will ultimately be compatible with global regulatory trends as well as comply with legislative directives in the European Union and the United States.

In the field of plant-derived oxygen scavengers in multilayer film packaging, one of the projects the Fraunhofer IVV has worked on is the use of natural, plant-derived antimicrobials for packaging. It says the application of packaging materials that release antimicrobial substances to food surfaces is an attractive option to reduce and inhibit undesirable microbial growth due to contamination and to prevent food loss — and natural antimicrobial compounds are preferred to synthetic substances.

Fraunhofer IVV has identified suitable antimicrobial substances pelargonium and olive leaf extract which are encapsulated to protect them during processing. It says they have been dispersed in polymers, coated on films, extruded and intensively tested.

Work so far indicates the natural antimicrobials are suitable for extrusion and coating, and can withstand the processing temperatures involved. Still to be determined is to find the right match between food and antimicrobial substance to avoid organoleptic, or taste changes in the food.

In a further study, a natural and plant-derived oxygen scavenger, gallic acid, was used in food packaging to provide additional protection to oxygen-sensitive food products. A mixture of gallic acid and sodium carbonate was incorporated in a bio-based multilayer packaging film produced by a three-step process of compounding, flat film extrusion and lamination.

Fraunhofer investigated the film surface color as well as oxygen absorption at different relative humidities and temperatures, and compared the oxygen absorption of the powder, monolayer film and multilayer film.

In conclusion, in plastics food contact packaging, there is a broad range of plastic resins possessing unique chemistries and physical properties. Recognizing these key property differences and remembering that all plastics are not necessarily compatible will lead to the careful selection of materials for food packaging applications.

For example, due to high as molded transparency harnessed to ultra-low carbonated gas permeation, polyethylene terephthalate (PET) is the perfect solution for large two-liter soda bottles. By comparison polypropylene (PP) is not a good fit here because it is not as clear when molded and more importantly lacks a carbonated gas barrier for soda. Food products and, in turn, plastics food contact packages are subject to several environmental influences.

Another important aspect to keep in mind is that while the development of regulatory systems for food contact materials in different parts of the globe may result in some movement toward a greater degree of global harmonization, the systems most assuredly are not harmonized at present.

Finally, movement toward more recycled food packaging and more focus on novel nanomaterials and how to regulate them are key trends to keep an eye on in the near future.