The chewed-up gum that befouls American sidewalks costs taxpayers millions of dollars in cleanups. Now researchers in Illinois say they have developed an
alternative that doesn’t stick to shoes. Will consumers bite?
The guys were out to bust some gum.
John Vann and Tony Muniz uncased their weapons-–5-foot-long hoses with brass-bristled nozzles. Then they blasted the enemy, which consisted of gum spit
out on a busy New York City corner.
The men used the bristles to scratch furiously at the hardened globules, their faces tight with concentration. “The blacker it is, the longer it’s been
there,” said Vann, of a sidewalk cleaning company called GumBusters.
He frowned at a black mound and gave it another jet of chemical steam. “That one’s been there two weeks,” he said, pointing to a raised rubbery pink spot.
He scowled at a white mound. “This one, probably one or two months.”
For the time being, GumBusters is one of the only solutions for American city dwellers sick of scraping sticky mess from their shoes. But 700 miles away,
researchers at the University of Illinois at Urbana-Champaign hope to use advances in agricultural technology to solve the problem for good. They say that
zein, a protein byproduct of corn-produced ethanol, promises to be a biodegradable alternative to synthetic bases currently used by chewing gum
manufacturers.
Sticky gum litters a New York City sidewalk corner. 
Professor Soo-Yeun Lee is at work in the sensory booth at the University of Illinois where panelists chewed and evaluated zein-based gum distraction-free. 
In an Illinois lab, a researcher twists zein, a natural byproduct of corn-ethanol production, like taffy. |
“If discarded in parks or lawns it may end up being eaten away by wildlife or digested by microorganisms,” said Professor Garciela
Padua, of the university’s Department of Food Science and Human Nutrition, who assisted in the research.
To be sure, many pedestrians across the United States would welcome sidewalks free of masticated filth. Cities spend millions of tax dollars annually in
cleanups. Half of Americans chew gum, averaging 170 servings per person per year, according to the Wm. Wrigley Jr. Company, which dominates the chewing gum
industry in sales. Last year, Wrigley’s, whose products include Juicy Fruit, Doublemint, and Orbit, reported net sales of $5.4 billion. The global market is
worth $20 billion and growing, which means more gum on the streets.
But Americans, who consume 40 percent of the world’s gum, remain largely unconcerned over spitting it out.
For that reason, Professor Soo-Yeun Lee at the University of Illinois began the research project in 2004. She announced the next year that her team had
successfully used zein to make a biodegradable gum that wouldn’t stick.
“You’re not going to worry about your kids getting it in their hair or getting it on the carpet,” said Phil Shane, a former member of the Illinois Corn
Marketing Board, which is funding the research. “If it got on your shoe, it would peel right off.”
Shane, who has chewed Lee’s prototype, said he tried to stick it to the bottom of a table. “It fell to the floor,” he said. “You just take a broom and
sweep it.”
Panelists selected to chew the cinnamon-coated prototype participated once a day for five weeks to rate its taste, texture, aroma, and mouth feel. Except
for the quick disappearance of flavor, they were pleased, Lee said.
After the study showed zein’s potential, Shane launched a company called Prairie Gold to make zein marketable to gum makers and other industries. Zein is
already used as a coating for photo-quality printing paper, glass adhesives and inks.
Shane may face competition. Professor Terence Cosgrove at the University of Bristol in Britain formed a spin-off company two years ago to market a
non-sticky-–but not biodegradable–- substance that he believed could be used as gum base as well.
Meanwhile, the world’s top gum producers are quietly conducting their own research into the non-sticky phenomenon.
Wrigley’s is working to figure out a solution to the problem of gum disposal without sacrificing taste and texture, and the zein research at Illinois is
one of the options the company is exploring. “We are working with our scientists, university researchers, the best and brightest,” said Chris Perille,
director of communications at Wrigley’s.
Cadbury Schweppes, which owns 26 percent of the global chewing gum market and is Wrigley’s closest competitor, is doing research of its own. “We believe
it is the responsibility of the individual,” said Tony Bilsborough, communications director at Cadbury, based in London, “but we do want to create something
that helps to prevent littering.”
When asked how long it will take before non-sticky gum shows up on shelves, Bilsborough said he did not know. Cosgrove refused to comment. Shane estimated
five years. “There is no magic bullet that would transform it overnight,” said Perille.
He added that Wrigley’s had patents to reduce adhesion, but added, “It’s a big leap from patent to commercialization.”
Lee said there is still important work to be done – namely perfecting the flavor, which was the prototype’s biggest disappointment. The current version’s
taste fades after two minutes, something even sidewalk-conscious consumers would reject.
“If you cannot mimic the exact kind of profile that current gum is providing to the consumers, it’s going to be difficult to sell,” said Lee, “even if it
has a lot of long-term value to the environment.”
