CHICAGO — Midway through the afternoon, when the belly yearns for snacks, three NutraSweet executives are going wild: cola, orange drink, citrus punch, chocolate milk, more cola, pound cake and crispy squares of coconut pie -- all test-kitchen concoctions made with artificial sweeteners.
They consume two servings of everything. In quick succession.
They wax exuberant about one of the pound cakes -- moist, crumbly and nicely browned.
"The person who cooked these said she never had such browning before," says Craig R. Petray, chief executive of NutraSweet Co.
In the bounty of goodies before them lies a vision of the future of sweetness -- a future, these executives hope, just as sweet and delectable as real sugar.
But, as researchers have discovered, the quest to find a perfect, consequence-free artificial sweetener is difficult, littered with cloying, metallic and just plain odd-tasting chemicals.
Today, the research is receiving fresh attention -- fueled by an expanding national waistline. Nutritionists believe that Americans' breathtaking intake of sugars in soft drinks and processed foods is partly to blame.
The U.S. Department of Agriculture estimates that the average American eats about 100 pounds of added sugars a year, up 30% since the 1980s.
Consumers are taking note, trying in small ways to clean up their act. Diet soft drink sales are growing at about 6% a year, while those of regular soft drinks are declining by as much as 2%.
After years of loading snacks with sugar, food manufacturers are developing more reduced-sugar brands so that consumers can have their cake and eat it.
To tackle the problem, some are cutting down slightly on sugar in their products, or artfully combining high-intensity artificial sweeteners to find just the right combinations to mimic real sugar.
Other companies are turning to the latest research in genetics and chemistry. Now there are humming labs, seeking out "enhancer" chemicals that accentuate the effects of real sugar, thus allowing less to be used.
Shaving away sugar is no easy business.
Sugar does much more than sweeten. It provides crumbliness to a cake's interior, crispness to its outside and a richer taste to a soft drink.
Despite decades of research, artificial sweeteners -- a $1-billion-a-year market in the U.S. -- still taste noticeably unnatural.
"You could probably line up 30 different sweeteners and I could tell you what each one was, no problem," says Susan Schiffman, a sweetness researcher at Duke University Medical Center.
The human lust for sweetness runs deep. Even newborn babies have an innate love of sugar-flavored water.
There is a sensible evolutionary reason for this: Sugar means fuel -- 15 calories in each teaspoon. Homing in on rich sources in nature -- fruits, berries, honey -- is a key for creatures as varied as flies, birds and dogs.
Unlike the super-sharp sensors for pheromones and poisons, human sweet receptors are naturally blunt so that people only notice significant sources of calories. As for sugar, the more the better.
It's an instinct that proved useful back when calories were scarce. It is far less beneficial in a land flowing with candy, super-sized soft drinks and doughnuts.
A problem with cutting sugar is that its sweetness is tricky to imitate.
Artificial sweeteners stick to the same receptor but to different parts, and with different speeds and tightness. Those factors translate into subtle differences in onset of taste, intensity and length of sweetness.
Sweetness aficionados have developed discerning palates.
"I can pick each one up and say, 'Ah, Ace-K ... ah, sugar ... ah, thaumatin,' " Schiffman says.
The first artificial sweetener was found in 1879 by accident.
Two chemists at Johns Hopkins University, Constantine Fahlberg and Ira Remsen, were trying to make new chemical dyes from coal tar derivatives when a vessel boiled over in the lab one day. Fahlberg failed to properly wash his hands before a meal and noted how sweet his fingers tasted.
He traced the sweetness back to a two-ringed chemical called benzoic acid sulfanilamide. Fully 300 times sweeter than sugar, it is indigestible by the body, and thus calorie-free. He later dubbed the chemical saccharin, from saccharum, the Latin word for sugar.
The pattern of serendipity has continued up until today.
Cyclamate, used in soft drinks until it was banned, was discovered in 1937 when University of Illinois graduate student Michael Sveda put his cigarette down near a compound he was testing as a possible anti-fever drug and later noticed he was smoking a sweet cigarette.
Aspartame was discovered in 1965 by chemist Jim Schlatter, who licked his finger while testing a new anti-ulcer drug for the pharmaceutical company G. D. Searle & Co.
Scientists now know of scores of sweet chemicals -- monellin, stevioside, thaumatin, lugduname, glycyrrhizin, maltitol and the tasty but toxic dulcin, which was used as a sweetener during World War I (and poisoned several children).