Plastics tech makes composting easier. But will businesses get on board?

A diner makes a salad in a compostable container.
A diner at the Rathskeller Cafe inside the Minnesota State Capitol makes a salad inside a compostable food container on Thursday.
Evan Frost | MPR News

Many eateries provide customers with cups and dishes that are recyclable. But they're not recyclable if people leave them smeared or mixed with food.

NatureWorks, a Minnetonka-based company half owned by agribusiness giant Cargill, has a solution for that problem: a compostable plastic. That means food waste and whatever was used to serve or eat it can be tossed into composting bins. No separation needed.

While most businesses aren't yet on board with compostable products, they're growing increasingly supportive.

State and local governments across the country are making it more expensive to just dump stuff in landfills or incinerators, and there are increasing mandates for more recycling and composting.

"There's almost a 50 percent tax practically on regular trash," said Jim Ibister, who oversees sustainability programs at Xcel Energy Center and St. Paul RiverCentre. "Everything we could get into the compost side of the business was better for us on the bottom line."

The complex Ibister oversees sent about 350 tons of waste to composters last year. That's about a quarter of the waste the center generated.

"Anything uneaten, that's going to be compostable," said spokesperson Ellen McNair. "Every single one of our utensils, that's compostable as well."

That means, with a few exceptions, people chowing down at the center can simply discard food, cups, plates, bowls and cutlery all in the same bin — no separating, thanks to the NatureWorks plastic.

Organic bins inside the Rathskeller Cafe.
The state Capitol's Rathskeller Cafe added an "Organics" trash bin upon re-opening after the renovation. The bin is meant for food waste but also takes the cafe's compostable silverware and containers.
Evan Frost | MPR News

The whole point is to try to make things as easy as possible for the public.

NatureWorks manufactures the plant-based plastic called Ingeo that is used to make the compostable plates and other items dispensed at Xcel Energy Center, the state Capitol, Target Field and other venues around the country.

"We take plant sugars and we ferment that sugar. So, it's a lot like making beer or wine," said company spokesperson Steve Davies. "Our process makes something called lactic acid. And we go through a plastic-making process and make a polymer or a plastic out of that lactic acid."

The environmental advantages of plant-based plastic are a selling point for NatureWorks, Davies said.

But commercial customers aren't going to buy products just because they're green.

"It has to work darn well, be tough and strong," Davies said. "It's got to be pretty price competitive."

Currently, a cup made from Ingeo may cost several cents more than other cups. But NatureWorks is trying to get prices on par with petroleum-based products.

More food vendors are realizing composting can make waste disposal simpler and cheaper, said Sarah Martinez, marketing director for Colorado-based Eco-Products, which uses Ingeo to make compostable containers and utensils.

But there are impediments to composting on a really large scale.

"Collecting and processing those products, a lot of work remains to be done on that front," Martinez said. "First of all, we need more commercial composting facilities in the country. "

Compostable forks, spoons and containers at the Rathskeller Cafe.
Diners at the Capitol's Rathskeller Cafe use compostable silverware and containers during the lunch hour on Thursday.
Evan Frost | MPR News

There are impediments to composting NatureWorks' Ingeo plastic on a small scale, too. It won't readily break down in backyard composting bins. It's meant to go to commercial composting facilities.

Still, experts see plenty of upside, especially for the environment. Food waste accounts for about a fifth of our trash.

Hennepin County recycling program manager Paul Kroening said the spread of compostable plastic could reduce the amount of food going to landfills.

"If packaging isn't compostable," Kroening said, "then what ultimately will happen is a lot of the food waste will end up in the garbage."

Locally, only Minneapolis, St. Louis Park and a handful of other cities offer residents curbside organics collection now. Relatively few businesses and commercial buildings have started programs.

But Kroening expects organics composting will be more common and convenient.

"It's the next generation of recycling," he said.