04-02 glass replace plastic

[Image above] Returning to the milkman model just might help reduce pollution and benefit glass packaging at the same time. Credit: Henry Hemming; Flickr CC BY 2.0

Glass and plastic are very different materials.

I am not just talking about the countless divergent materials properties of glass and plastics; I am instead fascinated by something a bit more inconsequential—how the materials continue their divergence even after they are discarded.

Whereas the majority of plastics ever produced are now tumbling across our planet as worthless hunks of discarded yet nearly eternally-linked monomers, discarded glass can tumble around for decades under the waves and actually gain value and desirability (as sea glass, glass can literally go from trash to treasure).

Sea glass—the ultimate trash to treasure. Credit: Ama Strachan; Flickr CC BY 2.0

Even more importantly than my musings, however, is that public perception of plastic and glass has also diverged substantially in recent times.

Advances in glass formulations and processes have made the material more durable, versatile, and suitable to a host of modern uses. And what is fascinating is that public perception of glass has similarly changed along the way, too. Today, glass is considered a material that is strong, tough, and even luxurious—so much so that it is favored for some of our most beloved tech.

For plastic, however, the story diverges in the opposite direction.

As a material, plastics are a technological marvel. They play a critical role in raising the standard of living, improving modern medicine, and enabling the technological revolution, as just a few significant examples.

Public perception of plastic, however, has sharply fallen since its heydey as a revolutionary material in the era surrounding WWII. Discarded plastics have not only polluted the environment—and with recycling essentially broken, the pollution problem is not getting any better—there have been widely reported health concerns linked to plastics exposure, including cancers, endocrine system disruptions, developmental defects, and reproductive effects.

So perhaps it is no surprise that many companies, organizations, governments, and geographic areas have recently vowed to reduce or eliminate their use of plastics, particularly consumption of single-use, disposable plastics.

According to 2015 figures from the United States Environmental Protection Agency, the U.S. discarded some 77.9 million U.S. tons of container and packaging waste in 2015. Of that total, 51.2 percent was composed of paper and cardboard, while 18.8 percent was plastic and 11.7 percent was glass (the remaining was 12.5 percent wood, 2.8 percent steel, and 2.4 percent aluminum).

So what does a trending shift away from plastic—especially for food and beverage packaging—mean for other materials?

“Many of today’s market trends influencing food and beverage packaging present strong opportunities for glass containers,” Lynn Bragg, president of the Glass Packaging Institute, writes in a 2018 Glass Worldwide article. “Consumers continue their desire for healthy, sustainable, premium products and glass packaging delivers.”

To be clear, glass was already once on top of the food and beverage packaging world. But plastic’s reduced cost and improved durability enabled it to reign supreme.

Just think about the last time you shopped at the grocery store—likely most of the products stocking the store’s aisles, coolers, and freezers were packaged in paper, cardboard, and plastic. That is, unless you were shopping in the alcoholic beverage section.

While plastic has gained favor in many food and beverage packaging sectors, glass’s lower permeability to oxygen and carbon dioxide has allowed the material to retain its title as packaging material of choice in the alcohol market.

Beer represented 56 percent of the sales volume for the glass container industry in 2017, according to the 2018 Glass Worldwide article. Other beverages, including non-alcoholic beverages, liquor, and wine, accounted for another 26 percent. The remaining approximately 18 percent contained food products.

But, there is some evidence that glass is gaining favor in the overall packaging market. An IHS Markit report from 2018 indicates that the public perception of plastic packaging is changing. “In a survey of European consumers, FEVE found that 85% of respondents preferred glass as a packaging material and that 73% thought it was a safer material for drink packaging.”

The report continues, “Although PET [polyethylene terephthalate] has a number of advantages as a food packaging material over glass, including cost and weight, the impact of using plastics as a packaging material on the environment is becoming a much more visible issue.”

Plastic, plastic, everywhere. Credit: Tony Webster; Flickr CC BY 2.0

Starting a new loop?

That issue—the impact of plastic packaging on the environment—is precipitating other changes as well. In addition to companies, organizations, and groups vowing to take action to eliminate plastic straws and ban disposable bags, other efforts are being proposed that would completely upend the way we view modern product packaging.

For instance, an initiative called Loop is bypassing the idea of disposable altogether and is instead building the concept of an infrastructure—and packaging—designed for continued reuse.

The idea is nostalgically similar to the milkman, who once continuously cycled glass bottles to and from our doorsteps.

Through Loop, consumers order the products they want—food items such as juice, ice cream, and oats, and personal products such as mouthwash, shampoo, deodorant, and diapers—which get delivered directly to their door.

Instead of being packaged in containers meant for a singular disposable use, the products are packaged in specially designed, nondisposable containers. Once those containers are empty, consumers save them and send the empties back to Loop.

Empty containers get cleaned and refilled for another use, with Loop’s goal to reuse packaging 100 times before it is discarded. To keep up the cycle, consumers pay a deposit for each container, and that deposit gets refunded once the empty packaging is returned to Loop—encouraging a loop of use, refill, and reuse.

Loop is more than an idea at this point—it is a fully developed program that is launching in some areas of the U.S. and France in spring 2019, according to the website. 

Complete with an already impressive list of participating companies, including Nestlé and PepsiCo, and offering well-known brands such as Häagen-Dazs, Tropicana, Crest, Pantene, Quaker, Clorox, Dove, and Pampers, Loop seems poised to potentially change the packaging game.

While Loop products’ special reusable packaging is not necessarily sans plastic, it does more heavily feature glass and metal materials, likely due to their superior durability across repeated uses and suitability to cleaning and sterilizing. For instance, items such as orange juice and mouthwash delivered through Loop will seemingly be packaged in glass bottles instead of plastic.

In addition to different materials, Loop products’ packaging presents unique design challenges as well. For instance, Häagen-Dazs ice cream ordered through Loop cannot be shipped in the standard disposable cardboard pints you would find in your grocery store freezer aisle. Instead, Nestlé designed special double-walled stainless steel ice cream vessels, which reportedly took 15 tries to get right.

Ultimately, it remains to be determined if Loop will work, or how well it will work. But the idea is an interesting solution to the dead-end lifecycle of how we use materials in the modern world. And, if successful, it could introduce a unique perspective for consumer packaging design and materials.

Similarly, as consumer preferences favor a shift away from disposable plastics, product and packaging challenges may also introduce new opportunities for other materials to solve those challenges—niches that plastic materials do not fit.

One example might even already be stocked on your grocery store’s shelves. Yoplait Oui stands out among many grocery store yogurt sections in that its individual serving cups are made of glass, not plastic.

And while this switch was largely dictated by process rather than preference—traditional cupped yogurt is fermented first and then packaged into individual cups, while Oui is fermented directly in the cup—it nonetheless demonstrates potential shifts and opportunities in the packaging market. In the case of Oui, glass solved a material challenge that plastic could not.

No glass here. Credit: Bob Mical; Flickr CC BY-NC 2.0

Of course, glass packaging has its drawbacks as well, most notably heavier weight and limited durability—plastic has risen to the top of many packaging markets because it is lighter weight and less likely to break. Both of those factors ultimately translate to reduced costs through lower shipping weights, reduced energy resources for product transport, and less product lost to breakage.

Yet despite glass’s drawbacks, the negative public perception of plastic coupled with its pollution and health problems may be enough to put glass back in favor for product packaging.

In Europe at least, data may be starting to reflect the seeming trend toward glass packaging. According to a recent release from the European Container Glass Federation FEVE, European glass packaging production increased 1 percent in volume and units in early 2018 compared to late 2017.

“The growth is in line with the full year 2017 data, which recorded a growth of 2% in weight terms and 2.4% in units and compares favourably with the historical trend since 2012,” the release cites. “Between 2012–2017, production has increased by almost 1.7 million tonnes (8.3% increase) or 6.4 billion units (8.9% increase) … Generally, all food and beverage market segments experienced a demand growth for glass…”

So the question still stands—can our newfound aversion to plastic prove to be a boon to glass? I can’t say for sure, but things clearly look interesting.