Diet Pepsi has secretly added a new artificial sweetener to its formula, in a desperate bid to improve its declining sales, it has been revealed.
The beverage maker added acesulfame potassium to boost its base sweetener aspartame, which is sensitive to heat and is susceptible to breaking down, the New York Post reported.
The newly formulated Diet Pepsi cans were found this weekend in New York, Omaha, Nebraska, and the San Francisco Bay Area.
PepsiCo officials said that the new product will be gradually rolled out, as retailers move their current inventory.
"It's not like a light switch. It'll start appearing as shelf space clears," company spokeswoman Andrea Canabal said.
The actual taste of the new Diet Pepsi shouldn't be any different, but the sweetness could have longer shelf life with acesulfame potassium.
According to the company, the ingredient boost was meant "to ensure consistency with every sip."
Diet Pepsi is now the nation's seventh most popular carbonated drink, with 4.9 percent of the market - down from 5.3 percent in 2000, according to Beverage Digest.
In that same time frame, rival Diet Coke that uses just aspartame has acquired market share of 9.6 percent from 8.7 percent.
Diet Coke has climbed to No. 2 among all soda pop in 2010, second only to regular Coke and is pushing regular Pepsi down to No. 3. (ANI)