Steps from the lobby of the Dr Pepper Snapple Group headquarters, a row of inauspicious Rubbermaid bins holds the crystallized future of the nation's third largest soft drink player.

The tubs contain sugar, the artificial sweetener aspartame and similar snowflake-like substances.

Like its competitors Coke and Pepsi, Texas-based Dr Pepper is deep in the hunt for a new sweetener that can replace existing artificial sweeteners. It has to taste like sugar yet be lower in calories. And it has to be natural.

The stakes are high. The Big Three soda makers lead an industry that's rounding out a decade of declining sales.

As regular sodas, and now diets, lose their fizz, soft drink makers are spending increasing amounts of time and energy looking for ways to sweeten the pot.

"This year will be the 10th year" of decline, said John Sicher, editor and publisher of the authoritative trade publication Beverage Digest. "Without new sweetener technology, I can't see a reason for that trend to change."

Carbonated soft drinks the fizzy water that's been around since the 1800s make up about 65 percent of sales of "liquid refreshment beverages." That's a roughly $120 billion retail category that includes everything from energy drinks to bottled water.

While price hikes have kept total soft drink revenue from tanking, the amount of soda sold (called volume) has been falling.

In 2013, total carbonated soft drink volume slid by 3 percent, according to Beverage Digest. That followed a 1 percent volume drop in both 2012 and 2011.

Between 2004 and 2013, sodas have seen a drop of 1.6 billion cases sold, according to Beverage Marketing Corp., a New York-based research and consulting firm.

The decline is especially steep in diet sodas.

For example, Dr Pepper's total volume slipped by a modest 0.2 percent last year, while Diet Dr Pepper lost 6.3 percent in 2013. Diet sales at rivals Coke and Pepsi have followed suit.

'VILIFIED UNJUSTLY'

The suspected culprit behind declines in both regular and diet sodas is the sweeteners.

Researchers and nutritionists have linked the consumption of regular soft drinks which can have up to 170 calories and 45 grams of sugar in a 12-ounce can to increasing U.S. obesity rates and development of Type 2 diabetes.

Drinking more than one can of regular soda per day can put consumers at increased risk of cardiovascular disease, according to the Centers for Disease Control.

David Thomas, executive vice president for research and development at Dr Pepper, thinks the soft drink industry has been "vilified unjustly" and counters that sugar-sweetened beverages represent just 6 percent of the average person's daily caloric intake.

On the diet side, some consumers have begun to shy away from artificial sweeteners amid reports linking at least one sweetener, aspartame, to an increased incidence of some cancers in lab rats.



Per capita sales of diet soft drinks have declined by about 25 percent since 2007 and are now lower than they were in 1998, said Michael F. Jacobson, executive director of the Center for Science in the Public Interest, a watchdog group.