Pepsi's natural sweetener version to be launched on Amazon

Coke and Pepsi are squaring off again, this time with natural sweeteners.

PepsiCo said Wednesday it plans to roll out a reduced-calorie version of its namesake soda made with sugar and stevia, a natural sweetener. Pepsi True will be sold on Amazon.com later this month before rolling out more broadly.

Meanwhile, rival Coca-Cola is testing Coca-Cola Life, which is also made with a mix of sugar and stevia and has fewer calories than its regular soda. That drink is expected to hit markets nationally by November.

As Americans keep cutting back on soda, the two beverage giants are hoping they can win back customers by addressing concerns about the high fructose corn syrup in regular soda as well as the artificial sweeteners in diet sodas.

Stevia aftertaste

The quest to come up with new formulas has intensified recently as sales of diet sodas have declined at even steeper rates than their full-calorie counterparts. Coke and Pepsi executives have blamed the trend on worries about artificial sweeteners like aspartame, which have no calories but are seen as processed and fake.

Simon Lowden, chief marketing officer for PepsiCo's North American beverage unit, noted in a phone interview that people are no longer focusing on calories alone, but also taking into account whether a product uses artificial ingredients.

Coke-Pepsi rivalry

Pepsi True will come in 7.5-ounce cans, each with 60 calories. Coca-Cola Life, which is being test-marketed at select locations in the southeastern U.S, comes in 8-ounce glass bottles, each with 60 calories as well.

• The skinny on sugars and sweeteners

Ali Dibadj, a Bernstein analyst, said in a note Wednesday that interviews with store managers indicated sales of Coca-Cola Life so far seem "satisfactory."

Both Coke and Pepsi have sold mid-calorie versions of their flagship sodas in the past, but those were made with different sweeteners. In 2012, PepsiCo also rolled out Pepsi Next, which has about half the calories of regular Pepsi.

Pepsi Next, which is still on shelves, is made with a mix of three artificial sweeteners and high fructose corn syrup. Lowden said he imagines Pepsi Next, which hasn't been performing strongly, will eventually be phased out in the U.S.