by Deborah Fleischer
Government facilities, colleges and universities, and corporations are jumping on the bioeconomy bandwagon by switching from petroleum-based plastic take-out items to compostable products made of renewable resources at their cafeterias. While greening lunches on the run might not seem like front-page news, these smaller efforts are paving the way for a larger transformation to a zero-waste green revolution, fed by corn and sugar.
One of the major barriers to switching from petroleum-based plastic to biobased to-go products has been cost. But with oil prices rising, and the market for biobased products growing, many expect the price gap to narrow.
Traditional foam "to-go" containers are made of polystyrene, while the clear plastic containers and bottles we see everywhere are made of polyethylene terephthalate (PET), polystyrene or polypropylene -- all petroleum-based plastic polymers. The ubiquitous paper coffee cup, and the paper take-out containers we see everywhere, also use a petroleum-based plastic coating to make them waterproof.
According to Green Seal, in 1997, 120 million pounds of foam polystyrene hinged containers were used in the U.S. food packaging industry and each American throws away an average of 100 polystyrene cups each year. Green Mountain Coffee Roasters recently estimated that last year Americans used 14.4 billion hot paper cups (placed end-to-end, this many cups would circle the world 55 times).
Not only do these plastic cups and take-out containers create garbage that ends up in the landfill for centuries to come (a polystyrene cup has an expected lifetime of over 500 years), they are made from non-renewable petrochemicals, and styrene, a key ingredient of polystyrene, is a suspected carcinogen and known hazardous substance.
Marin County, California, recently switched their Civic Center cafe from plastic to take-out containers, plates, and cups made from corn (PLA) and sugar cane fiber (bagasse). County Supervisor Charles McGlashan, who initiated the switch for the County, articulates, "It is all about walking your talk. If you are the kind of organization that has sustainability values and you want to walk your talk, you can't have a cafe filled with plastic."
To reduce waste, energy use, and emissions, Marin County offers patrons the option to eat-in using reusable ceramic plates, glasses, and cutlery. Another option is to encourage customers to bring their own cups and plates, by offering them a small discount. Still, many employees prefer to take their meals "to-go," which is where bioplastic comes in.
Choosing the Right Product
Summer intern Julie Goldrosen researched the choices for Marin County, and quickly discovered that San Francisco's Department of Environment, Bioneers, and companies such as Wild Oats and Newman's Own Organics have all successfully used them.
"When I asked people how it worked, everyone raved about it," exclaims Goldrosen. They were surprised by how much they look like regular plastic. That is when I knew it would be feasible to make the switch -- because the biobased products were comparable to what the cafe already had."
Here's a brief overview of the most popular biobased products:
- Polylactic acid (NatureWorks PLA): PLA is a fully biodegradable, compostable corn-based polymer made by NatureWorks LLC (owned by Cargill). At their Nebraska plant, locally harvested corn is broken down into corn sugar (also known as dextrose). The dextrose is fermented and distilled into a substance called lactic acid. The lactic acid is transformed into PLA pellets, which are sent to manufacturers to be turned into clear food packaging, as well as other products, including water bottles, CD players, auto parts, and even coffins.
- To date, PLA has been used only for cold food and drinks because it does not function well for hot foods (over 110 degrees). However, Green Mountain Coffee Roasters and International Paper just launched a new eco-friendly hot paper cup with a PLA lining that makes the cup heat resistant.
- NatureWorks recently started purchasing Renewable Energy Certificates (RECs) to offset greenhouse gases at their plant, reducing the environmental footprint of producing the PLA.
