The use of plastic in food packaging will continue into 2019, while companies struggle with the perception of plastic as “waste” and environmental pariah. The issue was raised in the Wall Street Journal Heard on the Street section on Dec. 31, 2018, “Plastic Is Food’s Next Headache,” which called 2019 “a tipping point” for major consumer goods manufacturers such as P&G, Unilever and Nestlé as a “public backlash over plastic waste is forcing makers of top household brands to rethink their packaging.”
Because of its properties—keeping food fresh, prolonging shelf life and providing barrier protection from light and oxygen—plastic is too valuable for food processors to abandon, especially since there are no viable replacements. Attempts to be “green,” such as Coke’s “plant bottle” and the use of other bioplastic materials, do not work on a large scale and remain “niche” applications.
Other recent technologies that are gaining some traction include returning the used bottles and food containers to a company that de-polymerizes them, breaking them down into monomers that can be re-polymerized. There are also return schemes being introduced that will “re-use” bottles and food containers, but that leaves big questions about how eco-friendly that idea is given transportation costs as well as the cost of sterilizing the bottles and containers for refilling.
In an article in Phys.org this past summer, “Starch can replace normal plastic in food packaging” by Karlstad University, the authors claim that eventually all petroleum-based material in food packaging will have to be replaced with biobased material. The university’s research shows that “a mixture of starch and other polymers forms an equally effective protective barrier” that can be used in paper-based food packaging to prevent water or oxygen from penetrating the packaging and spoiling the foodstuff inside.”
Finding a good, biobased replacement for plastic to use in food packaging has been the Holy Grail of that industry for a number of years. “Research done at Karlstad University shows that a mixture of lignin from wood and starch from, for example, potatoes or maize potentially can fulfill this function just as well as plastic,” said researcher Asif Javed. “If new materials are to be used, they have to be at least as good as or better than petroleum-based material—regarding extending the shelf life of food, as well as the cost and effectivity of manufacture and transport. Although such material is not 100% based on renewable resources, it has the important advantage of naturally degrading without leaving behind dangerous microplastics, should it end up in forests, lakes or oceans.”
One report released in December by Million Insights, a distributor of market research reports, on the growth of the global paper packaging material market noted that it would “witness significant growth due to its ideal substitute for plastics in packaging and manufacturing sectors” until 2022. Much of this demand for paper as a replacement for plastics in packaging is due to paper’s biodegradability.
A second report released by Million Insights, “Biopolymer Coatings Market to Exhibit Significant Demand from Paper Packaging, Food and Beverages Industry until 2022,” noted that the growing use of biopolymer coatings in “green packaging” will be aided by “favorable government regulations” that are “expected to boost market expansion.” The report cited biopolymer coatings’ advantages such as “lower toxicity levels, lower cost and higher operational efficiency” as contributing to this growth. “Paper packaging is considered one of the fastest growing segments in the biopolymer coating market with substantial revenue generation in the last few years,” said the report’s summary.
There is one downside that these reports neglect to mention: Paper that has been coated with a polymer or even a bio-polymer cannot be recycled with conventional polymers such as PET, PP and so forth. By coating paper packaging with a polymer or biobased polymer material, these food processors have essentially turned a recyclable bottle or container into one that is non-recyclable.
The drive to eventually make all plastic packaging recyclable will fall flat if the major food processors push for paper packaging that requires a polymer or biopolymer coating to provide a fraction of the benefits of existing plastic packaging!
Image courtesy momius/Adobe Stock.