Gum is getting chewed out, but one portion of the market is staying sweet.
U.S. consumption of gum sank by a fifth in volume and a tenth in sales during the last five years alone, according to research firm Rabobank International, but a host of companies willing to make good on consumers' dislike of artificial sounding products have yet to see their bubble burst.
Enter the world of so-called "natural" gums.
"People are wanting something simple and uncomplicated, and when you rattle off the ingredients of chewing gum it sounds anything but simple and uncomplicated," said Nicholas Fereday, executive director and senior analyst of food and consumer trends at Rabobank International.
"Ingredients haven't been part of the buying decision until recently," said Deborah Schimberg, CEO of Glee Gum, an all-natural brand. "People are getting more savvy and people are getting more critical—they're looking at the ingredient list with more knowledge and more concern."
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Glee Gum started in 1998, long before the current shift in consumer preferences. As all-natural, Glee Gum is the only gum in the U.S. to be non-GMO project verified. It also uses fair trade sugar in its classic gum recipe.
"It has no artificial coloring, no artificial flavoring, no artificial preservatives. … In addition, we pack our gum in 100 percent recycled materials. We also are the only gum that uses chicle, a natural material that all gum used to be made from," Schimberg said. "What we've tried to focus on is saying to consumers, 'Look at what you're eating!' A snack shouldn't harm you. You shouldn't have to think about it twice.."
According to SPINS, a research firm that specializes in natural products, Glee Gum is the top-selling all-natural gum brand.
Even tough Glee has been around for 16 years, it is "growing tremendously," Schimberg said. "Our sales are up over 30 percent this year. And we are doing some tests with major big box stores, too. There's interest in natural gum that goes beyond niche markets,"
However, private label companies still make up less than 1 percent of the entire $4 billion gum market, according to Rabobank.
Glee's peppermint gum costs $11.52 for a package of a dozen 18-piece packs on Walmart.com (or 5 cents per piece of gum). By comparison, Wrigley's Extra sugar-free peppermint gum costs $14.95 for a package of 10 15-stick packs (or 10 cents a stick) on the website.
PUR gum, founded in 2010, is more of a newcomer on the niche market for less-artificial gum. The company operates with the slogan of "kick aspartame" and offers naturally sweetened, low-calorie gums.
Aspartame, Fereday said, is a key artificial ingredient when it comes to consumer sentiment. "That's one of the sweeteners that—though it's been proven safe time and time again—consumers feel bad about. By taking that out gum, companies can turn things around," he said.
PUR Gum heavily emphasizes its use of the natural sweetener xylitol, which is derived from non-GMO corn fibers, rather than a chemical sweetener, and that has given it a sweet spot in the market.
"PUR Gum has been growing at about 200-300 percent per year in sales since our start in 2010," spokeswoman Reanna Mardinger said. "We believe that the largest growth opportunities are still forthcoming."
On Walmart.com a 12 count of 9-piece packs of PUR peppermint gum is $15.84 (11 cents a piece).
CEO Jay Klein said PUR is trying to convert "curiosity into consumption" by embarking on a campaign of getting samples into the hands of new and potential customers.
"We're very cognizant of all the line extension opportunities in terms of consumer demand and where to drive the market," he said. "We've had great experience growing, and will continue pushing those numbers."
But while natural gum companies are growing in response to consumer preference shifts, obstacles remain when it comes to further expansion.
Schimberg said there's stiff competition for prime space in supermarkets.
"We feel that more and more consumers are looking for natural confectionary and natural snacks, but it's tricky when contracts (with supermarkets) have been made and fees are so high and essentially controlled by contracts with big companies," she said.
And prime space for impulse buying—at the register—may not be so prime anymore since shoppers now have diversions with their smartphones, she said.
—By Bo McMillan, special to CNBC.com
CORRECTION: This story has been updated to reflect that PUR Gum's xylitol is derived from non-GMO corn fibers.